Planets - Blog Posts

NASA’s New Planet Hunter Reveals a Sky Full of Stars

NASA’s newest planet-hunting satellite — the Transiting Exoplanet Survey Satellite, or TESS for short — has just released its first science image using all of its cameras to capture a huge swath of the sky! TESS is NASA’s next step in the search for planets outside our solar system, called exoplanets.

This spectacular image, the first released using all four of TESS’ cameras, shows the satellite’s full field of view. It captures parts of a dozen constellations, from Capricornus (the Sea Goat) to Pictor (the Painter’s Easel) — though it might be hard to find familiar constellations among all these stars! The image even includes the Large and Small Magellanic Clouds, our galaxy’s two largest companion galaxies.

The science community calls this image “first light,” but don’t let that fool you — TESS has been seeing light since it launched in April. A first light image like this is released to show off the first science-quality image taken after a mission starts collecting science data, highlighting a spacecraft’s capabilities.

TESS has been busy since it launched from NASA’s Kennedy Space Center in Cape Canaveral, Florida. First TESS needed to get into position, which required a push from the Moon. After nearly a month in space, the satellite passed about 5,000 miles from the Moon, whose gravity gave it the boost it needed to get into a special orbit that will keep it stable and maximize its view of the sky.

During those first few weeks, we also got a sneak peek of the sky through one of TESS’s four cameras. This test image captured over 200,000 stars in just two seconds! The spacecraft was pointed toward the constellation Centaurus when it snapped this picture. The bright star Beta Centauri is visible at the lower left edge, and the edge of the Coalsack Nebula is in the right upper corner.

After settling into orbit, scientists ran a number of checks on TESS, including testing its ability to collect a set of stable images over a prolonged period of time. TESS not only proved its ability to perform this task, it also got a surprise! A comet named C/2018 N1 passed through TESS’s cameras for about 17 hours in July.

The images show a treasure trove of cosmic curiosities. There are some stars whose brightness changes over time and asteroids visible as small moving white dots. You can even see an arc of stray light from Mars, which is located outside the image, moving across the screen.

Now that TESS has settled into orbit and has been thoroughly tested, it’s digging into its main mission of finding planets around other stars. How will it spot something as tiny and faint as a planet trillions of miles away? The trick is to look at the star!

So far, most of the exoplanets we’ve found were detected by looking for tiny dips in the brightness of their host stars. These dips are caused by the planet passing between us and its star – an event called a transit. Over its first two years, TESS will stare at 200,000 of the nearest and brightest stars in the sky to look for transits to identify stars with planets.

TESS will be building on the legacy of NASA’s Kepler spacecraft, which also used transits to find exoplanets. TESS’s target stars are about 10 times closer than Kepler’s, so they’ll tend to be brighter. Because they're closer and brighter, TESS’s target stars will be ideal candidates for follow-up studies with current and future observatories.

TESS is challenging over 200,000 of our stellar neighbors to a staring contest! Who knows what new amazing planets we’ll find?

The TESS mission is led by MIT and came together with the help of many different partners. You can keep up with the latest from the TESS mission by following mission updates.

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What’s Up For September 2018?

Outstanding views Venus, Jupiter, Saturn and Mars with the naked eye!

You'll have to look quickly after sunset to catch Venus. And through binoculars or a telescope, you'll see Venus's phase change dramatically during September - from nearly half phase to a larger thinner crescent!

Jupiter, Saturn and Mars continue their brilliant appearances this month. Look southwest after sunset.

Use the summer constellations help you trace the Milky Way.

Sagittarius: where stars and some brighter clumps appear as steam from the teapot.

Aquila: where the Eagle's bright Star Altair, combined with Cygnus's Deneb, and Lyra's Vega mark the Summer Triangle. 

Cassiopeia, the familiar "w"- shaped constellation completes the constellation trail through the Summer Milky Way. Binoculars will reveal double stars, clusters and nebulae. 

Between September 12th and the 20th, watch the Moon pass from near Venus, above Jupiter, to the left of Saturn and finally above Mars! 

Both Neptune and brighter Uranus can be spotted with some help from a telescope this month.

Look at about 1:00 a.m. local time or later in the southeastern sky. You can find Mercury just above Earth's eastern horizon shortly before sunrise. Use the Moon as your guide on September 7 and 8th.

And although there are no major meteor showers in September, cometary dust appears in another late summer sight, the morning Zodiacal light. Try looking for it in the east on moonless mornings very close to sunrise. To learn more about the Zodiacal light, watch "What's Up" from March 2018.

Watch the full What’s Up for September Video: 

There are so many sights to see in the sky. To stay informed, subscribe to our What’s Up video series on Facebook.

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Why Bennu? 10 Reasons

After traveling for two years and billions of kilometers from Earth, the OSIRIS-REx probe is only a few months away from its destination: the intriguing asteroid Bennu. When it arrives in December, OSIRIS-REx will embark on a nearly two-year investigation of this clump of rock, mapping its terrain and finding a safe and fruitful site from which to collect a sample.

The spacecraft will briefly touch Bennu’s surface around July 2020 to collect at least 60 grams (equal to about 30 sugar packets) of dirt and rocks. It might collect as much as 2,000 grams, which would be the largest sample by far gathered from a space object since the Apollo Moon landings. The spacecraft will then pack the sample into a capsule and travel back to Earth, dropping the capsule into Utah's west desert in 2023, where scientists will be waiting to collect it.

This years-long quest for knowledge thrusts Bennu into the center of one of the most ambitious space missions ever attempted. But the humble rock is but one of about 780,000 known asteroids in our solar system. So why did scientists pick Bennu for this momentous investigation? Here are 10 reasons:

1. It's close to Earth

Unlike most other asteroids that circle the Sun in the asteroid belt between Mars and Jupiter, Bennu’s orbit is close in proximity to Earth's, even crossing it. The asteroid makes its closest approach to Earth every 6 years. It also circles the Sun nearly in the same plane as Earth, which made it somewhat easier to achieve the high-energy task of launching the spacecraft out of Earth's plane and into Bennu's. Still, the launch required considerable power, so OSIRIS-REx used Earth’s gravity to boost itself into Bennu’s orbital plane when it passed our planet in September 2017.

2. It's the right size

Asteroids spin on their axes just like Earth does. Small ones, with diameters of 200 meters or less, often spin very fast, up to a few revolutions per minute. This rapid spinning makes it difficult for a spacecraft to match an asteroid's velocity in order to touch down and collect samples. Even worse, the quick spinning has flung loose rocks and soil, material known as "regolith" — the stuff OSIRIS-REx is looking to collect — off the surfaces of small asteroids. Bennu’s size, in contrast, makes it approachable and rich in regolith. It has a diameter of 492 meters, which is a bit larger than the height of the Empire State Building in New York City, and rotating once every 4.3 hours.

3. It's really old

Bennu is a leftover fragment from the tumultuous formation of the solar system. Some of the mineral fragments inside Bennu could be older than the solar system. These microscopic grains of dust could be the same ones that spewed from dying stars and eventually coalesced to make the Sun and its planets nearly 4.6 billion years ago. But pieces of asteroids, called meteorites, have been falling to Earth's surface since the planet formed. So why don't scientists just study those old space rocks? Because astronomers can't tell (with very few exceptions) what kind of objects these meteorites came from, which is important context. Furthermore, these stones, that survive the violent, fiery decent to our planet's surface, get contaminated when they land in the dirt, sand, or snow. Some even get hammered by the elements, like rain and snow, for hundreds or thousands of years. Such events change the chemistry of meteorites, obscuring their ancient records.

4. It's well preserved

Bennu, on the other hand, is a time capsule from the early solar system, having been preserved in the vacuum of space. Although scientists think it broke off a larger asteroid in the asteroid belt in a catastrophic collision between about 1 and 2 billion years ago, and hurtled through space until it got locked into an orbit near Earth's, they don’t expect that these events significantly altered it.

5. It might contain clues to the origin of life

Analyzing a sample from Bennu will help planetary scientists better understand the role asteroids may have played in delivering life-forming compounds to Earth. We know from having studied Bennu through Earth- and space-based telescopes that it is a carbonaceous, or carbon-rich, asteroid. Carbon is the hinge upon which organic molecules hang. Bennu is likely rich in organic molecules, which are made of chains of carbon bonded with atoms of oxygen, hydrogen, and other elements in a chemical recipe that makes all known living things. Besides carbon, Bennu also might have another component important to life: water, which is trapped in the minerals that make up the asteroid.

6. It contains valuable materials

Besides teaching us about our cosmic past, exploring Bennu close-up will help humans plan for the future. Asteroids are rich in natural resources, such as iron and aluminum, and precious metals, such as platinum. For this reason, some companies, and even countries, are building technologies that will one day allow us to extract those materials. More importantly, asteroids like Bennu are key to future, deep-space travel. If humans can learn how to extract the abundant hydrogen and oxygen from the water locked up in an asteroid’s minerals, they could make rocket fuel. Thus, asteroids could one day serve as fuel stations for robotic or human missions to Mars and beyond. Learning how to maneuver around an object like Bennu, and about its chemical and physical properties, will help future prospectors.

7. It will help us better understand other asteroids

Astronomers have studied Bennu from Earth since it was discovered in 1999. As a result, they think they know a lot about the asteroid's physical and chemical properties. Their knowledge is based not only on looking at the asteroid, but also studying meteorites found on Earth, and filling in gaps in observable knowledge with predictions derived from theoretical models. Thanks to the detailed information that will be gleaned from OSIRIS-REx, scientists now will be able to check whether their predictions about Bennu are correct. This work will help verify or refine telescopic observations and models that attempt to reveal the nature of other asteroids in our solar system.

8. It will help us better understand a quirky solar force ...

Astronomers have calculated that Bennu’s orbit has drifted about 280 meters (0.18 miles) per year toward the Sun since it was discovered. This could be because of a phenomenon called the Yarkovsky effect, a process whereby sunlight warms one side of a small, dark asteroid and then radiates as heat off the asteroid as it rotates. The heat energy thrusts an asteroid either away from the Sun, if it has a prograde spin like Earth, which means it spins in the same direction as its orbit, or toward the Sun in the case of Bennu, which spins in the opposite direction of its orbit. OSIRIS-REx will measure the Yarkovsky effect from close-up to help scientists predict the movement of Bennu and other asteroids. Already, measurements of how this force impacted Bennu over time have revealed that it likely pushed it to our corner of the solar system from the asteroid belt.

9. ... and to keep asteroids at bay

One reason scientists are eager to predict the directions asteroids are drifting is to know when they're coming too-close-for-comfort to Earth. By taking the Yarkovsky effect into account, they’ve estimated that Bennu could pass closer to Earth than the Moon is in 2135, and possibly even closer between 2175 and 2195. Although Bennu is unlikely to hit Earth at that time, our descendants can use the data from OSIRIS-REx to determine how best to deflect any threatening asteroids that are found, perhaps even by using the Yarkovsky effect to their advantage.

10. It's a gift that will keep on giving

Samples of Bennu will return to Earth on September 24, 2023. OSIRIS-REx scientists will study a quarter of the regolith. The rest will be made available to scientists around the globe, and also saved for those not yet born, using techniques not yet invented, to answer questions not yet asked.

Read the web version of this week’s “Solar System: 10 Things to Know” article HERE.

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Solar System 10 Things: Dust in the Wind, on Mars & Well Beyond

To most of us, dust is an annoyance. Something to be cleaned up, washed off or wiped away. But these tiny particles that float about and settle on surfaces play an important role in a variety of processes on Earth and across the solar system. So put away that feather duster for a few moments, as we share with you 10 things to know about dust.

1. "Dust" Doesn't Mean Dirty, it Means Tiny

Not all of what we call "dust" is made of the same stuff. Dust in your home generally consists of things like particles of sand and soil, pollen, dander (dead skin cells), pet hair, furniture fibers and cosmetics. But in space, dust can refer to any sort of fine particles smaller than a grain of sand. Dust is most commonly bits of rock or carbon-rich, soot-like grains, but in the outer solar system, far from the Sun's warmth, it's also common to find tiny grains of ice as well. Galaxies, including our Milky Way, contain giant clouds of fine dust that are light years across – the ingredients for future generations of planetary systems like ours.

2. Some Are Big, Some Are Small (and Big Ones Tend to Fall)

Dust grains come in a range of sizes, which affects their properties. Particles can be extremely tiny, from only a few tens of nanometers (mere billionths of a meter) wide, to nearly a millimeter wide. As you might expect, smaller dust grains are more easily lifted and pushed around, be it by winds or magnetic, electrical and gravitational forces. Even the gentle pressure of sunlight is enough to move smaller dust particles in space. Bigger particles tend to be heavier, and they settle out more easily under the influence of gravity.

For example, on Earth, powerful winds can whip up large amounts of dust into the atmosphere. While the smaller grains can be transported over great distances, the heavier particles generally sink back to the ground near their source. On Saturn's moon Enceladus, jets of icy dust particles spray hundreds of miles up from the surface; the bigger particles are lofted only a few tens of miles (or kilometers) and fall back to the ground, while the finest particles escape the moon's gravity and go into orbit around Saturn to create the planet's E ring.

3. It’s EVERYWHERE

Generally speaking, the space between the planets is pretty empty, but not completely so. Particles cast off by comets and ground up bits of asteroids are found throughout the solar system. Take any volume of space half a mile (1 kilometer) on a side, and you’d average a few micron-sized particles (grains the thickness of a red blood cell).

Dust in the solar system was a lot more abundant in the past. There was a huge amount of it present as the planets began to coalesce out of the disk of material that formed the Sun. In fact, motes of dust gently sticking together were likely some of the earliest seeds of the planet-building process. But where did all that dust come from, originally? Some of it comes from stars like our Sun, which blow off their outer layers in their later years. But lots of it also comes from exploding stars, which blast huge amounts of dust and gas into space when they go boom.

4. From a Certain Point of View

Dust is easier to see from certain viewing angles. Tiny particles scatter light depending on how big their grains are. Larger particles tend to scatter light back in the direction from which it came, while very tiny particles tend to scatter light forward, more or less in the direction it was already going. Because of this property, structures like planetary rings made of the finest dusty particles are best viewed with the Sun illuminating them from behind. For example, Jupiter's rings were only discovered after the Voyager 1 spacecraft passed by the planet, where it could look back and see them backlit by the Sun. You can see the same effect looking through a dusty windshield at sunset; when you face toward the Sun, the dust becomes much more apparent.

5. Dust Storms Are Common on Mars

Local dust storms occur frequently on Mars, and occasionally grow or merge to form regional systems, particularly during the southern spring and summer, when Mars is closest to the Sun. On rare occasions, regional storms produce a dust haze that encircles the planet and obscures surface features beneath. A few of these events may become truly global storms, such as one in 1971 that greeted the first spacecraft to orbit Mars, our Mariner 9. In mid-2018, a global dust storm enshrouded Mars, hiding much of the Red Planet's surface from view and threatening the continued operation of our uber long-lived Opportunity rover. We’ve also seen global dust storms in 1977, 1982, 1994, 2001 and 2007.

Dust storms will likely present challenges for future astronauts on the Red Planet. Although the force of the wind on Mars is not as strong as portrayed in an early scene in the movie "The Martian," dust lofted during storms could affect electronics and health, as well as the availability of solar energy.

6. Dust From the Sahara Goes Global

Earth's largest, hottest desert is connected to its largest tropical rain forest by dust. The Sahara Desert is a near-uninterrupted brown band of sand and scrub across the northern third of Africa. The Amazon rain forest is a dense green mass of humid jungle that covers northeast South America. But after strong winds sweep across the Sahara, a dusty cloud rises in the air, stretches between the continents, and ties together the desert and the jungle.

This trans-continental journey of dust is important because of what is in the dust. Specifically, the dust picked up from the Bodélé Depression in Chad -- an ancient lake bed where minerals composed of dead microorganisms are loaded with phosphorus. Phosphorus is an essential nutrient for plant proteins and growth, which the nutrient-poor Amazon rain forest depends on in order to flourish.

7. Rings and Things

The rings of the giant planets contain a variety of different dusty materials. Jupiter's rings are made of fine rock dust. Saturn's rings are mostly pure water ice, with a sprinkling of other materials. (Side note about Saturn's rings: While most of the particles are boulder-sized, there's also lots of fine dust, and some of the fainter rings are mostly dust with few or no large particles.) Dust in the rings of Uranus and Neptune is made of dark, sooty material, probably rich in carbon.

Over time, dust gets removed from ring systems due to a variety of processes. For example, some of the dust falls into the planet's atmosphere, while some gets swept up by the planets' magnetic fields, and other dust settles onto the surfaces of the moons and other ring particles. Larger particles eventually form new moons or get ground down and mixed with incoming material. This means rings can change a lot over time, so understanding how the tiniest ring particles are being moved about has bearing on the history, origins and future of the rings.

8. Moon Dust is Clingy and Might Make You Sick

So, dust is kind of a thing on the Moon. When the Apollo astronauts visited the Moon, they found that lunar dust quickly coated their spacesuits and was difficult to remove. It was quite abrasive, causing wear on their spacesuit fabrics, seals and faceplates. It also clogged mechanisms like the joints in spacesuit limbs, and interfered with fasteners like zippers and Velcro. The astronauts also noted that it had a distinctive, pungent odor, not unlike gunpowder, and it was an eye and lung irritant.

Many of these properties apparently can be explained by the fact that lunar dust particles are quite rough and jagged. While dust particles on Earth get tumbled and ground by the wind into smoother shapes, this sort of weathering doesn't happen so much on the Moon. The roughness of Moon dust grains makes it very easy for them to cling to surfaces and scratch them up. It also means they're not the sort of thing you would want to inhale, as their jagged edges could damage delicate tissues in the lung.

9. Dust is What Makes Comets So Pretty

Most comets are basically clods of dust, rock and ice. They spend most of their time far from the Sun, out in the refrigerated depths of the outer solar system, where they're peacefully dormant. But when their orbits carry them closer to the Sun -- that is, roughly inside the orbit of Jupiter -- comets wake up. In response to warming temperatures, the ices on and near their surfaces begin to turn into gases, expanding outward and away from the comet, and creating focused jets of material in places. Dust gets carried away by this rapidly expanding gas, creating a fuzzy cloud around the comet's nucleus called a coma. Some of the dust also is drawn out into a long trail -- the comet's tail.

10. We're Not the Only Ones Who're So Dusty

Dust in our solar system is continually replenished by comets whizzing past the Sun and the occasional asteroid collision, and it's always being moved about, thanks to a variety of factors like the gravity of the planets and even the pressure of sunlight. Some of it even gets ejected from our solar system altogether.

With telescopes, we also observe dusty debris disks around many other stars. As in our own system, the dust in such disks should evolve over time, settling on planetary surfaces or being ejected, and this means the dust must be replenished in those star systems as well. So studying the dust in our planetary environs can tell us about other systems, and vice versa. Grains of dust from other planetary systems also pass through our neighborhood -- a few spacecraft have actually captured and analyzed some them -- offering us a tangible way to study material from other stars.

Read the full version of ‘Solar System: 10 Things to Know’ article HERE. 

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What’s a Blood Moon? And Other Lunar Eclipse Questions.

Tonight, Australians, Africans, Europeans, Asians and South Americans will have the opportunity to see the longest lunar eclipse of the century. Sorry North America. 

Lunar eclipses occur about 2-4 times per year, when the Moon passes into the Earth’s shadow. In order to see a lunar eclipse, you must be on the night side of the Earth, facing the Moon, when the Earth passes in between the Moon and the Sun. Need help visualizing this? Here you go:

What’s the difference between a solar eclipse and a lunar eclipse?

An easy way to remember the difference between a solar eclipse and a lunar eclipse is that the word ‘eclipse’ refers to the object that is being obscured. During a solar eclipse, the Moon blocks the Sun from view. During a lunar eclipse, the Earth’s shadow obscures the Moon.

Why does the Moon turn red?  

You may have heard the term ‘Blood Moon’ for a lunar eclipse. When the Moon passes into the Earth’s shadow, it turns red. This happens for the exact same reason that our sunrises and sunsets here on Earth are brilliant shades of pinks and oranges. During a lunar eclipse, the only light reaching the Moon passes through the Earth’s atmosphere. The bluer, shorter wavelength light scatters and the longer wavelength red light passes through and makes it to the Moon.

What science can we learn from a lunar eclipse?

"During a lunar eclipse, the temperature swing is so dramatic that it’s as if the surface of the Moon goes from being in an oven to being in a freezer in just a few hours,” said Noah Petro, project scientist for our Lunar Reconnaissance Orbiter, or LRO, at our Goddard Space Flight Center in Greenbelt, Maryland.

The Diviner team from LRO measures temperature changes on the Moon through their instrument on the spacecraft as well as through a thermal camera on Earth. How quickly or slowly the lunar surface loses heat helps scientists determine characteristics of lunar material, including its composition and physical properties.

When is the next lunar eclipse?

North Americans, don’t worry. If skies are clear, you can see the next lunar eclipse on January 21, 2019. The eclipse will be visible to North Americans, South Americans, and most of Africa and Europe.

To keep an eye on the Moon with us check out nasa.gov/moon or follow us on Twitter and Facebook.

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What’s Up - July 2018

What's Up for July?

Mars is closest to Earth since 2003!

July’s night skies feature Mars opposition on the 27th, when Mars, Earth, and the Sun all line up, and Mars’ closest approach to Earth since 2003 on the 31st. 

If you've been sky watching for 15 years or more, then you'll remember August 2003, when Mars approached closer to Earth than it had for thousands of years.

It was a very small percentage closer, but not so much that it was as big as the moon as some claimed.   

Astronomy clubs everywhere had long lines of people looking through their telescopes at the red planet, and they will again this month!

 If you are new to stargazing, this month and next will be a great time to check out Mars. 

Through a telescope, you should be able to make out some of the light and dark features, and sometimes polar ice. Right now, though, a huge Martian dust storm is obscuring many features, and less planetary detail is visible.

July 27th is Mars opposition, when Mars, Earth, and the Sun all line up, with Earth directly in the middle.

A few days later on July 31st is Mars' closest approach. That's when Mars and Earth are nearest to each other in their orbits around the Sun. Although there will be a lot of news focusing on one or the other of these two dates, Mars will be visible for many months.

By the end of July, Mars will be visible at sunset.

But the best time to view it is several hours after sunset, when Mars will appear higher in the sky.

Mars will still be visible after July and August, but each month it will shrink in apparent size as it travels farther from Earth in its orbit around the Sun.

On July 27th a total lunar eclipse will be visible in Australia, Asia, Africa, Europe and South America.

For those viewers, Mars will be right next to the eclipsing moon!

Next month will feature August's summer Perseids. It's not too soon to plan a dark sky getaway for the most popular meteor shower of the year! 

Watch the full What’s Up for July Video:

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10 Things: Mars Helicopter

When our next Mars rover lands on the Red Planet in 2021, it will deliver a groundbreaking technology demonstration: the first helicopter to ever fly on a planetary body other than Earth. This Mars Helicopter will demonstrate the first controlled, powered, sustained flight on another world. It could also pave the way for future missions that guide rovers and gather science data and images at locations previously inaccessible on Mars. This exciting new technology could change the way we explore Mars.

1. Its body is small, but its blades are mighty.

One of the biggest engineering challenges is getting the Mars Helicopter’s blades just right. They need to push enough air downward to receive an upward force that allows for thrust and controlled flight — a big concern on a planet where the atmosphere is only one percent as dense as Earth’s. “No helicopter has flown in those flight conditions – equivalent to 100,000 feet (30,000 meters) on Earth,” said Bob Balaram, chief engineer for the project at our Jet Propulsion Laboratory.

2. It has to fly in really thin Martian air.

To compensate for Mars’ thin atmosphere, the blades must spin much faster than on an Earth helicopter, and the blade size relative to the weight of the helicopter has to be larger too. The Mars Helicopter’s rotors measure 4 feet wide (about 1.2 meters) long, tip to tip. At 2,800 rotations per minute, it will spin about 10 times faster than an Earth helicopter. At the same time, the blades shouldn’t flap around too much, as the helicopter’s design team discovered during testing. Their solution: make the blades more rigid. “Our blades are much stiffer than any terrestrial helicopter’s would need to be,” Balaram said.   The body, meanwhile, is tiny — about the size of a softball. In total, the helicopter will weigh just under 4 pounds (1.8 kilograms).

3. It will make up to five flights on Mars.

Over a 30-day period on Mars, the helicopter will attempt up to five flights, each time going farther than the last. The helicopter will fly up to 90 seconds at a time, at heights of up to 10 to 15 feet (3 to 5 meters). Engineers will learn a lot about flying a helicopter on Mars with each flight, since it’s never been done before!

4. The Mars Helicopter team has already completed groundbreaking tests.

Because a helicopter has never visited Mars before, the Mars Helicopter team has worked hard to figure out how to predict the helicopter’s performance on the Red Planet. “We had to invent how to do planetary helicopter testing on Earth,” said Joe Melko, deputy chief engineer of Mars Helicopter, based at JPL.

The team, led by JPL and including members from JPL, AeroVironment Inc.,  Ames Research Center, and Langley Research Center, has designed, built and tested a series of test vehicles.

In 2016, the team flew a full-scale prototype test model of the helicopter in the 25-foot (7.6-meter) space simulator at JPL. The chamber simulated the low pressure of the Martian atmosphere. More recently, in 2018, the team built a fully autonomous helicopter designed to operate on Mars, and successfully flew it in the 25-foot chamber in Mars-like atmospheric density.

Engineers have also exercised the rotors of a test helicopter in a cold chamber to simulate the low temperatures of Mars at night. In addition, they have taken design steps to deal with Mars-like radiation conditions. They have also tested the helicopter’s landing gear on Mars-like terrain. More tests are coming to see how it performs with Mars-like winds and other conditions.

5. The camera is as good as your cell phone camera.

The helicopter’s first priority is successfully flying on Mars, so engineering information takes priority. An added bonus is its camera. The Mars Helicopter has the ability to take color photos with a 13-megapixel camera — the same type commonly found in smart phones today. Engineers will attempt to take plenty of good pictures.

6. It’s battery-powered, but the battery is rechargeable.

The helicopter requires 360 watts of power for each second it hovers in the Martian atmosphere – equivalent to the power required by six regular lightbulbs. But it isn’t out of luck when its lithium-ion batteries run dry. A solar array on the helicopter will recharge the batteries, making it a self-sufficient system as long as there is adequate sunlight. Most of the energy will be used to keep the helicopter warm, since nighttime temperatures on Mars plummet to around minus 130 degrees Fahrenheit (minus 90 Celsius). During daytime flights, temperatures may rise to a much warmer minus 13 to minus 58 degrees Fahrenheit to (minus 25 to minus 50 degrees Celsius) — still chilly by Earth standards. The solar panel makes an average of 3 watts of power continuously during a 12-hour Martian day.

7. The helicopter will be carried to Mars under the belly of the rover.

Somewhere between 60 to 90 Martian days (or sols) after the Mars 2020 rover lands, the helicopter will be deployed from the underside of the rover. Mars Helicopter Delivery System on the rover will rotate the helicopter down from the rover and release it onto the ground. The rover will then drive away to a safe distance.

8. The helicopter will talk to the rover.

The Mars 2020 rover will act as a telecommunication relay, receiving commands from engineers back on Earth and relaying them to the helicopter. The helicopter will then send images and information about its own performance to the rover, which will send them back to Earth. The rover will also take measurements of wind and atmospheric data to help flight controllers on Earth.

9. It has to fly by itself, with some help.

Radio signals take time to travel to Mars — between four and 21 minutes, depending on where Earth and Mars are in their orbits — so instantaneous communication with the helicopter will be impossible. That means flight controllers can’t use a joystick to fly it in real time, like a video game. Instead, they need to send commands to the helicopter in advance, and the little flying robot will follow through. Autonomous systems will allow the helicopter to look at the ground, analyze the terrain to look how fast it’s moving, and land on its own.

10. It could pave the way for future missions.

A future Mars helicopter could scout points of interest, help scientists and engineers select new locations and plan driving routes for a rover. Larger standalone helicopters could carry science payloads to investigate multiple sites at Mars. Future helicopters could also be used to fly to places on Mars that rovers cannot reach, such as cliffs or walls of craters. They could even assist with human exploration one day. Says Balaram: "Someday, if we send astronauts, these could be the eyes of the astronauts across Mars.”

Read the full version of this week’s ‘10 Things to Know’ article on the web HERE.

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Solar System: 10 Things to Know

Movie Night

Summer break is just around the corner. Hang a sheet from the clothesline in the backyard and fire up the projector for a NASA movie night.

1. Mars in a Minute

Back in the day, movies started with a cartoon. Learn the secrets of the Red Planet in these animated 60 second chunks.

2. Crash of the Titans

Watch two galaxies collide billions of years from now in this high-definition visualization.

3. Tour the Moon in 4K

Wait for the dark of the waning Moon next weekend to take in this 4K tour of our constant celestial companion.

4. Seven Years of the Sun

Watch graceful dances in the Sun’s atmosphere in this series of videos created by our 24/7 Sun-sentinel, the Solar Dynamic Observatory (SDO).

5. Light ‘Em Up

Crank up the volume and learn about NASA science for this short video about some of our science missions, featuring a track by Fall Out Boy.

6. Bennu’s Journey

Follow an asteroid from its humble origins to its upcoming encounter with our spacecraft in this stunning visualization.

7. Lunar Landing Practice

Join Apollo mission pilots as they fly—and even crash—during daring practice runs for landing on the Moon.

8. Earthrise

Join the crew of Apollo 8 as they become the first human beings to see the Earth rise over the surface of the Moon.

9. Musical Descent to Titan

Watch a musical, whimsical recreation of the 2005 Huygens probe descent to Titan, Saturn’s giant moon.

10. More Movies

Our Goddard Scientific Visualization Studio provides a steady stream of fresh videos for your summer viewing pleasure. Come back often and enjoy.

Read the full version of this article on the web HERE. 

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What’s Up - June 2018

What’s Up For June?

Jupiter and Venus at sunset, Mars, Saturn and Vesta until dawn.

First up is Venus. It reaches its highest sunset altitude for the year this month and sets more than two hours after sunset.

You can't miss Jupiter, only a month after its opposition--when Earth was directly between Jupiter and the Sun.

The best time to observe Jupiter through a telescope is 10:30 p.m. at the beginning of the month and as soon as it's dark by the end of the month.  

Just aim your binoculars at the bright planet for a view including the four Galilean moons. Or just enjoy Jupiter with your unaided eye!

Saturn is at opposition June 27th, when it and the Sun are on opposite sides of Earth. It rises at sunset and sets at sunrise. Great Saturn viewing will last several more months. The best views this month will be just after midnight.

All year, the rings have been tilted wide open--almost 26 degrees wide this month--giving us a great view of Saturn's distinctive rings.

The tilt offers us a view of the north polar region, so exquisitely imaged by the Cassini spacecraft.

Near Saturn, the brightest asteroid--Vesta--is so bright that it can be seen with your unaided eye. It will be visible for several months.

A detailed star chart will help you pick out the asteroid from the stars. The summer Milky way provides a glittery backdrop.

Finally, Mars grows dramatically in brightness and size this month and is visible by 10:30 p.m. by month end.

The best views are in the early morning hours. Earth's closest approach with Mars is only a month away. It's the closest Mars has been to us since 2003.

Watch the full What’s Up for June Video: 

There are so many sights to see in the sky. To stay informed, subscribe to our What’s Up video series on Facebook. Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com.  

Solar System 10 Things to Know: Planetary Atmospheres

Every time you take a breath of fresh air, it’s easy to forget you can safely do so because of Earth’s atmosphere. Life on Earth could not exist without that protective cover that keeps us warm, allows us to breathe and protects us from harmful radiation—among other things.

What makes Earth’s atmosphere special, and how do other planets’ atmospheres compare? Here are 10 tidbits:

1. On Earth, we live in the troposphere, the closest atmospheric layer to Earth’s surface. “Tropos” means “change,” and the name reflects our constantly changing weather and mixture of gases. 

It’s 5 to 9 miles (8 to 14 kilometers) thick, depending on where you are on Earth, and it’s the densest layer of atmosphere. When we breathe, we’re taking in an air mixture of about 78 percent nitrogen, 21 percent oxygen and 1 percent argon, water vapor and carbon dioxide. More on Earth’s atmosphere›

2. Mars has a very thin atmosphere, nearly all carbon dioxide. Because of the Red Planet’s low atmospheric pressure, and with little methane or water vapor to reinforce the weak greenhouse effect (warming that results when the atmosphere traps heat radiating from the planet toward space), Mars’ surface remains quite cold, the average surface temperature being about -82 degrees Fahrenheit (minus 63 degrees Celsius). More on the greenhouse effect›

3. Venus’ atmosphere, like Mars’, is nearly all carbon dioxide. However, Venus has about 154,000 times more carbon dioxide in its atmosphere than Earth (and about 19,000 times more than Mars does), producing a runaway greenhouse effect and a surface temperature hot enough to melt lead. A runaway greenhouse effect is when a planet’s atmosphere and surface temperature keep increasing until the surface gets so hot that its oceans boil away. More on the greenhouse effect›

4. Jupiter likely has three distinct cloud layers (composed of ammonia, ammonium hydrosulfide and water) in its "skies" that, taken together, span an altitude range of about 44 miles (71 kilometers). The planet's fast rotation—spinning once every 10 hours—creates strong jet streams, separating its clouds into dark belts and bright zones wrapping around the circumference of the planet. More on Jupiter›

5. Saturn’s atmosphere—where our Cassini spacecraft ended its 13 extraordinary years of exploration of the planet—has a few unusual features. Its winds are among the fastest in the solar system, reaching speeds of 1,118 miles (1,800 kilometers) per hour. Saturn may be the only planet in our solar system with a warm polar vortex (a mass of swirling atmospheric gas around the pole) at both the North and South poles. Also, the vortices have “eye-wall clouds,” making them hurricane-like systems like those on Earth.

Another uniquely striking feature is a hexagon-shaped jet streamencircling the North Pole. In addition, about every 20 to 30 Earth years, Saturn hosts a megastorm (a great storm that can last many months). More on Saturn›

6. Uranus gets its signature blue-green color from the cold methane gas in its atmosphere and a lack of high clouds. The planet’s minimum troposphere temperature is 49 Kelvin (minus 224.2 degrees Celsius), making it even colder than Neptune in some places. Its winds move backward at the equator, blowing against the planet’s rotation. Closer to the poles, winds shift forward and flow with the planet’s rotation. More on Uranus›

7. Neptune is the windiest planet in our solar system. Despite its great distance and low energy input from the Sun, wind speeds at Neptune surpass 1,200 miles per hour (2,000 kilometers per hour), making them three times stronger than Jupiter’s and nine times stronger than Earth’s. Even Earth's most powerful winds hit only about 250 miles per hour (400 kilometers per hour). Also, Neptune’s atmosphere is blue for the very same reasons as Uranus’ atmosphere. More on Neptune›

8. WASP-39b, a hot, bloated, Saturn-like exoplanet (planet outside of our solar system) some 700 light-years away, apparently has a lot of water in its atmosphere. In fact, scientists estimate that it has about three times as much water as Saturn does. More on this exoplanet›

9. A weather forecast on “hot Jupiters”—blistering, Jupiter-like exoplanets that orbit very close to their stars—might mention cloudy nights and sunny days, with highs of 2,400 degrees Fahrenheit (about 1,300 degrees Celsius, or 1,600 Kelvin). Their cloud composition depends on their temperature, and studies suggest that the clouds are unevenly distributed. More on these exoplanets›

10. 55 Cancri e, a “super Earth” exoplanet (a planet outside of our solar system with a diameter between Earth’s and Neptune’s) that may be covered in lava, likely has an atmosphere containing nitrogen, water and even oxygen–molecules found in our atmosphere–but with much higher temperatures throughout. Orbiting so close to its host star, the planet could not maintain liquid water and likely would not be able to support life. More on this exoplanet›

Read the full version of this week’s Solar System 10 Things to Know HERE.

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The Hunt for New Worlds Continues with TESS

We're getting ready to start our next mission to find new worlds! The Transiting Exoplanet Survey Satellite (TESS) will find thousands of planets beyond our solar system for us to study in more detail. It's preparing to launch from our Kennedy Space Center at Cape Canaveral in Florida.

Once it launches, TESS will look for new planets that orbit bright stars relatively close to Earth. We're expecting to find giant planets, like Jupiter, but we're also predicting we'll find Earth-sized planets. Most of those planets will be within 300 light-years of Earth, which will make follow-up studies easier for other observatories.

TESS will find these new exoplanets by looking for their transits. A transit is a temporary dip in a star's brightness that happens with predictable timing when a planet crosses between us and the star. The information we get from transits can tell us about the size of the planet relative to the size of its star. We've found nearly 3,000 planets using the transit method, many with our Kepler space telescope. That's over 75% of all the exoplanets we've found so far!

TESS will look at nearly the entire sky (about 85%) over two years. The mission divides the sky into 26 sectors. TESS will look at 13 of them in the southern sky during its first year before scanning the northern sky the year after.

What makes TESS different from the other planet-hunting missions that have come before it? The Kepler mission (yellow) looked continually at one small patch of sky, spotting dim stars and their planets that are between 300 and 3,000 light-years away. TESS (blue) will look at almost the whole sky in sections, finding bright stars and their planets that are between 30 and 300 light-years away.

TESS will also have a brand new kind of orbit (visualized below). Once it reaches its final trajectory, TESS will finish one pass around Earth every 13.7 days (blue), which is half the time it takes for the Moon (gray) to orbit. This position maximizes the amount of time TESS can stare at each sector, and the satellite will transmit its data back to us each time its orbit takes it closest to Earth (orange).

Kepler's goal was to figure out how common Earth-size planets might be. TESS's mission is to find exoplanets around bright, nearby stars so future missions, like our James Webb Space Telescope, and ground-based observatories can learn what they're made of and potentially even study their atmospheres. TESS will provide a catalog of thousands of new subjects for us to learn about and explore.

The TESS mission is led by MIT and came together with the help of many different partners. Learn more about TESS and how it will further our knowledge of exoplanets, or check out some more awesome images and videos of the spacecraft. And stay tuned for more exciting TESS news as the spacecraft launches!

Watch the Launch!

*April 16 Update*

Launch teams are standing down today to conduct additional Guidance Navigation and Control analysis, and teams are now working towards a targeted launch of the Transiting Exoplanet Survey Satellite (TESS) on Wednesday, April 18. The TESS spacecraft is in excellent health, and remains ready for launch. TESS will launch on a Falcon 9 rocket from Space Launch Complex 40 at Cape Canaveral Air Force Station in Florida.

For more information and updates, visit: https://blogs.nasa.gov/tess/

Live Launch Coverage!

TESS is now slated to launch on Wednesday, April 18 on a SpaceX Falcon 9 rocket from our Kennedy Space Center in Florida.

Watch HERE.

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Solar System: 10 Things to Know This Week

Planets Outside Our Solar System

Let the planet-hunting begin!

Our Transiting Exoplanet Survey Satellite (TESS), which will scan the skies to look for planets beyond our solar system—known as exoplanets—is now in Florida to begin preparations for launch in April. Below, 10 Things to know about the many, many unknown planets out there awaiting our discovery.

1—Exo-what?

We call planets in our solar system, well, planets, but the many planets we’re starting to discover outside of our solar system are called exoplanets. Basically, they’re planets that orbit another star.

2—All eyes on TRAPPIST-1.

Remember the major 2016 announcement that we had discovered seven planets 40 light-years away, orbiting a star called TRAPPIST-1? Those are all exoplanets. (Here’s a refresher.)

3—Add 95 new ones to that.

Just last month, our Kepler telescope discovered 95 new exoplanets beyond our solar system (on top of the thousands of exoplanets Kepler has discovered so far). The total known planet count beyond our solar system is now more than 3,700. The planets range in size from mostly rocky super-Earths and fluffy mini-Neptunes, to Jupiter-like giants. They include a new planet orbiting a very bright star—the brightest star ever discovered by Kepler to have a transiting planet.

4—Here comes TESS.

How many more exoplanets are out there waiting to be discovered? TESS will monitor more than 200,000 of the nearest and brightest stars in search of transit events—periodic dips in a star’s brightness caused by planets passing in front—and is expected to find thousands of exoplanets.

5—With a sidekick, too.

Our upcoming James Webb Space Telescope, will provide important follow-up observations of some of the most promising TESS-discovered exoplanets. It will also allow scientists to study their atmospheres and, in some special cases, search for signs that these planets could support life.

6—Prepped for launch.

TESS is scheduled to launch on a SpaceX Falcon 9 rocket from Cape Canaveral Air Force Station nearby our Kennedy Space Center in Florida, no earlier than April 16, pending range approval.

7—A groundbreaking find.

In 1995, 51 Pegasi b (also called "Dimidium") was the first exoplanet discovered orbiting a star like our Sun. This find confirmed that planets like the ones in our solar system could exist elsewhere in the universe.

8—Trillions await.

A recent statistical estimate places, on average, at least one planet around every star in the galaxy. That means there could be a trillion planets in our galaxy alone, many of them in the range of Earth’s size.

9—Signs of life.

Of course, our ultimate science goal is to find unmistakable signs of current life. How soon can that happen? It depends on two unknowns: the prevalence of life in the galaxy and a bit of luck. Read more about the search for life.

10—Want to explore the galaxy?

No need to be an astronaut. Take a trip outside our solar system with help from our Exoplanet Travel Bureau.

Read the full version of this week’s ‘10 Things to Know’ article HERE. 

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Solar System: 10 Things to Know This Week

Week of March 5: Great Shots Inspiring views of our solar system and beyond

1-Mars-By-Numbers

“The first TV image of Mars, hand colored strip-by-strip, from Mariner 4 in 1965. The completed image was framed and presented to JPL director, William H. Pickering. Truly a labor of love for science!” -Kristen Erickson, NASA Science Engagement and Partnerships Director

2-Night Life

“There are so many stories to this image. It is a global image, but relates to an individual in one glance. There are stories on social, economic, population, energy, pollution, human migration, technology meets science, enable global information, etc., that we can all communicate with similar interests under one image.” -Winnie Humberson, NASA Earth Science Outreach Manager

3-Pale Blue Dot

“Whenever I see this picture, I wonder...if another species saw this blue dot what would they say and would they want to discover what goes on there...which is both good and bad. However, it would not make a difference within the eternity of space—we’re so insignificant...in essence just dust in the galactic wind—one day gone forever.”

-Dwayne Brown, NASA Senior Communications Official

4-Grand Central

“I observed the Galactic Center with several X-ray telescopes before Chandra, including the Einstein Observatory and ROSAT. But the Chandra image looks nothing like those earlier images, and it reminded me how complex the universe really is. Also I love the colors.” -Paul Hertz, Director, NASA Astrophysics Division

5-Far Side Photobomb

“This image from the Deep Space Climate Observatory (DSCOVR) satellite captured a unique view of the Moon as it moved in front of the sunlit side of Earth in 2015. It shows a view of the farside of the Moon, which faces the Sun, that is never directly visible to us here on Earth. I found this perspective profoundly moving and only through our satellite views could this have been shared.” -Michael Freilich, Director NASA Earth Science Division

6-”Shocking, Exciting and Wonderful”

“Pluto was so unlike anything I could imagine based on my knowledge of the Solar System. It showed me how much about the outer solar system we didn’t know. Truly shocking, exciting and wonderful all at the same time.” -Jim Green, Director, NASA Planetary Science Division

7-Slices of the Sun

“This is an awesome image of the Sun through the Solar Dynamic Observatory’s many filters. It is one of my favorites.” - Peg Luce, Director, NASA Heliophysics Division (Acting)

8-Pluto’s Cold, Cold Heart

“This high-resolution, false color image of Pluto is my favorite. The New Horizons flyby of Pluto on July 14, 2015 capped humanity’s initial reconnaissance of every major body in the solar system. To think that all of this happened within our lifetime! It’s a reminder of how privileged we are to be alive and working at NASA during this historic era of space exploration.” - Laurie Cantillo, NASA Planetary Science Public Affairs Officer

9-Family Portrait

“The Solar System family portrait, because it is a symbol what NASA exploration is really about: Seeing our world in a new and bigger way.” - Thomas H. Zurbuchen, Associate Administrator, NASA Science Mission Directorate

10-Share Your Favorite Space Shots

Tag @NASASolarSystem on your favorite social media platform with a link to your favorite image and few words about why it makes your heart thump.

Check out the full version of this article HERE.

Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com.   

What’s Up - March 2018

What’s Up For March?

Several Planets and the Zodiacal Light!

This month, at sunset, catch elusive Mercury, bright Venus, the Zodiacal Light, Mars, Saturn and Jupiter between midnight and dawn!

Both Venus and Mercury play the part of "evening stars" this month. At the beginning of the month they appear low on the western horizon.

The Moon itself joins the pair from March 18th through the 20th. 

The Moon skims by the Pleiades star cluster and Taurus's bright red star Aldebaran on the next few evenings, March 21 through the 23rd.

Jupiter, king of the planets, rises just before midnight this month and earlier by month end. 

Even through the smallest telescope or average binoculars, you should see the 4 Galilean moons, Europa, Io, Callisto and Ganymede.

The March morning sky offers dazzling views of Mars and Saturn all month long.

Through a telescope, you can almost make out some of the surface features on Mars.

Look a little farther into Mars' future and circle May 5th with a red marker. When our InSight spacecraft launches for its 6 month journey to the Red Planet, Mars will be easily visible to your unaided eye. 

Keep watching Mars as it travels closer to Earth. It will be closest in late July, when the red planet will appear larger in apparent diameter than it has since 2003!

You are in for a real treat if you can get away to a dark sky location on a moonless night this month -- the Zodiacal Light and the Milky Way intersect! 

The Zodiacal light is a faint triangular glow seen from a dark sky just after sunset in the spring or just before sunrise in the fall.

The more familiar Milky Way is one of the spiral arms of our galaxy. 

What we're seeing is sunlight reflecting off dust grains that circle the Sun in the inner solar system. These dust grains journey across our sky in the ecliptic, the same plane as the Moon and the planets.

Watch the full What’s Up for March Video: 

There are so many sights to see in the sky. To stay informed, subscribe to our What’s Up video series on Facebook. Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com.   

Solar System: 10 Things to Know This Week

Pioneer Days

Someone’s got to be first. In space, the first explorers beyond Mars were Pioneers 10 and 11, twin robots who charted the course to the cosmos.

1-Before Voyager

Voyager, with its outer solar system tour and interstellar observations, is often credited as the greatest robotic space mission. But today we remember the plucky Pioneers, the spacecraft that proved Voyager’s epic mission was possible.

2-Where No One Had Gone Before

Forty-five years ago this week, scientists still weren’t sure how hard it would be to navigate the main asteroid belt, a massive field of rocky debris between Mars and Jupiter. Pioneer 10 helped them work that out, emerging from first the first six-month crossing in February 1973. Pioneer 10 logged a few meteoroid hits (fewer than expected) and taught engineers new tricks for navigating farther and farther beyond Earth.

3-Trailblazer No. 2

Pioneer 11 was a backup spacecraft launched in 1973 after Pioneer 10 cleared the asteroid belt. The new mission provided a second close look at Jupiter, the first close-up views of Saturn and also gave Voyager engineers plotting an epic multi-planet tour of the outer planets a chance to practice the art of interplanetary navigation.

4-First to Jupiter

Three-hundred and sixty-three years after humankind first looked at Jupiter through a telescope, Pioneer 10 became the first human-made visitor to the Jovian system in December 1973. The spacecraft spacecraft snapped about 300 photos during a flyby that brought it within 81,000 miles (about 130,000 kilometers) of the giant planet’s cloud tops.

5-Pioneer Family

Pioneer began as a Moon program in the 1950s and evolved into increasingly more complicated spacecraft, including a Pioneer Venus mission that delivered a series of probes to explore deep into the mysterious toxic clouds of Venus. A family portrait (above) showing (from left to right) Pioneers 6-9, 10 and 11 and the Pioneer Venus Orbiter and Multiprobe series. Image date: March 11, 1982. 

6-A Pioneer and a Pioneer

Classic rock has Van Halen, we have Van Allen. With credits from Explorer 1 to Pioneer 11, James Van Allen was a rock star in the emerging world of planetary exploration. Van Allen (1914-2006) is credited with the first scientific discovery in outer space and was a fixture in the Pioneer program. Van Allen was a key part of the team from the early attempts to explore the Moon (he’s pictured here with Pioneer 4) to the more evolved science platforms aboard Pioneers 10 and 11.

7-The Farthest...For a While

For more than 25 years, Pioneer 10 was the most distant human-made object, breaking records by crossing the asteroid belt, the orbit of Jupiter and eventually even the orbit of Pluto. Voyager 1, moving even faster, claimed the most distant title in February 1998 and still holds that crown.

8-Last Contact

We last heard from Pioneer 10 on Jan. 23, 2003. Engineers felt its power source was depleted and no further contact should be expected. We tried again in 2006, but had no luck. The last transmission from Pioneer 11 was received in September 1995. Both missions were planned to last about two years.

9-Galactic Ghost Ships

Pioneers 10 and 11 are two of five spacecraft with sufficient velocity to escape our solar system and travel into interstellar space. The other three—Voyagers 1 and 2 and New Horizons—are still actively talking to Earth. The twin Pioneers are now silent. Pioneer 10 is heading generally for the red star Aldebaran, which forms the eye of Taurus (The Bull). It will take Pioneer over 2 million years to reach it. Pioneer 11 is headed toward the constellation of Aquila (The Eagle) and will pass nearby in about 4 million years.

10-The Original Message to the Cosmos

Years before Voyager’s famed Golden Record, Pioneers 10 and 11 carried the original message from Earth to the cosmos. Like Voyager’s record, the Pioneer plaque was the brainchild of Carl Sagan who wanted any alien civilization who might encounter the craft to know who made it and how to contact them. The plaques give our location in the galaxy and depicts a man and woman drawn in relation to the spacecraft.

Read the full version of this week’s 10 Things article HERE. 

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Help Explore Your Own Solar Neighborhood

We’re always making amazing discoveries about the farthest reaches of our universe, but there’s also plenty of unexplored territory much closer to home.

Our “Backyard Worlds: Planet 9” is a citizen science project that asks curious people like you — yes, you there! — to help us spot objects in the area around our own solar system like brown dwarfs. You could even help us figure out if our solar system hosts a mysterious Planet 9!

In 2009, we launched the Wide-field Infrared Survey Explorer (WISE). Infrared radiation is a form of light that humans can’t see, but WISE could. It scans the sky for infrared light, looking for galaxies, stars and asteroids. Later on, scientists started using it to search for near-Earth objects (NEOWISE) like comets and asteroids.

These searches have already turned up so much data that researchers have trouble hunting through all of it. They can’t do it on their own. That’s why we asked everyone to chip in. If you join Backyard Worlds: Planet 9, you’ll learn how to look at noisy images of space and spot previously unidentified objects. 

You’ll figure out how to tell the difference between real objects, like planets and stars, and artifacts. Artifacts are blurry blobs of light that got scattered around in WISE’s instruments while it was looking at the sky. These “optical ghosts” sometimes look like real objects.

Why can’t we use computers to do this, you ask? Well, computers are good at lots of things, like crunching numbers. But when it comes to recognizing when something’s a ghostly artifact and when it’s a real object, humans beat software all the time. After some practice, you’ll be able to recognize which objects are real and which aren’t just by watching them move!

One of the things our citizen scientists look for are brown dwarfs, which are balls of gas too big to be planets and too small to be stars. These objects are some of our nearest neighbors, and scientists think there’s probably a bunch of them floating around nearby, we just haven’t been able to find all of them yet. 

But since Backyard Worlds launched on February 15, 2016, our volunteers have spotted 432 candidate brown dwarfs. We’ve been able to follow up 20 of these with ground-based telescopes so far, and 17 have turned out to be real!

Image Credit: Ryan Trainor, Franklin and Marshall College

How do we know for sure that we’ve spotted actual, bona fide, authentic brown dwarfs? Well, like with any discovery in science, we followed up with more observation. Our team gets time on ground-based observatories like the InfraRed Telescope Facility in Hawaii, the Magellan Telescope in Chile (pictured above) and the Apache Point Observatory in New Mexico and takes a closer look at our candidates. And sure enough, our participants found 17 brown dwarfs!

But we’re not done! There’s still lots of data to go through. In particular, we want your help looking for a potential addition to our solar system’s census: Planet 9. Some scientists think it’s circling somewhere out there past Pluto. No one has seen anything yet, but it could be you! Or drop by and contribute to our other citizen science projects like Disk Detective.

Congratulations to the citizen scientists who spotted these 17 brown dwarfs: Dan Caselden, Rosa Castro, Guillaume Colin, Sam Deen, Bob Fletcher, Sam Goodman, Les Hamlet, Khasan Mokaev, Jörg Schümann and Tamara Stajic.

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Jupiter’s vibrant bands of light belts and dark regions appear primed for their close-up during our Juno spacecraft’s 10th flyby on Feb. 7. This flyby was a gravity science positioned pass. During orbits that highlight gravity experiments, Juno is positioned toward Earth in a way that allows both transmitters to downlink data in real-time to one of the antennas of our Deep Space Network. All of Juno’s science instruments and the spacecraft’s JunoCam were in operation during the flyby, collecting data that is now being returned to Earth. The science behind this beautifully choreographed image will help us understand the origin and structure of the planet beneath those lush, swirling clouds.

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Solar System: 10 Things to Know This Week

January 8: Images for Your Computer or Phone Wallpaper

Need some fresh perspective? Here are 10 vision-stretching images for your computer desktop or phone wallpaper. These are all real pictures, sent recently by our planetary missions throughout the solar system. You'll find more of our images at solarsystem.nasa.gov/galleries, images.nasa.gov and www.jpl.nasa.gov/spaceimages.

Applying Wallpaper: 1. Click on the screen resolution you would like to use. 2. Right-click on the image (control-click on a Mac) and select the option 'Set the Background' or 'Set as Wallpaper' (or similar).

1. The Fault in Our Mars

This image from our Mars Reconnaissance Orbiter (MRO) of northern Meridiani Planum shows faults that have disrupted layered deposits. Some of the faults produced a clean break along the layers, displacing and offsetting individual beds.

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2. Jupiter Blues

Our Juno spacecraft captured this image when the spacecraft was only 11,747 miles (18,906 kilometers) from the tops of Jupiter's clouds -- that's roughly as far as the distance between New York City and Perth, Australia. The color-enhanced image, which captures a cloud system in Jupiter's northern hemisphere, was taken on Oct. 24, 2017, when Juno was at a latitude of 57.57 degrees (nearly three-fifths of the way from Jupiter's equator to its north pole) and performing its ninth close flyby of the gas giant planet.

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3. A Farewell to Saturn

After more than 13 years at Saturn, and with its fate sealed, our Cassini spacecraft bid farewell to the Saturnian system by firing the shutters of its wide-angle camera and capturing this last, full mosaic of Saturn and its rings two days before the spacecraft's dramatic plunge into the planet's atmosphere on Sept. 15, 2017.

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4. All Aglow

Saturn's moon Enceladus drifts before the rings, which glow brightly in the sunlight. Beneath its icy exterior shell, Enceladus hides a global ocean of liquid water. Just visible at the moon's south pole (at bottom here) is the plume of water ice particles and other material that constantly spews from that ocean via fractures in the ice. The bright speck to the right of Enceladus is a distant star. This image was taken in visible light with the Cassini spacecraft narrow-angle camera on Nov. 6, 2011.

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5. Rare Encircling Filament

Our Solar Dynamics Observatory came across an oddity this week that the spacecraft has rarely observed before: a dark filament encircling an active region (Oct. 29-31, 2017). Solar filaments are clouds of charged particles that float above the Sun, tethered to it by magnetic forces. They are usually elongated and uneven strands. Only a handful of times before have we seen one shaped like a circle. (The black area to the left of the brighter active region is a coronal hole, a magnetically open region of the Sun).

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6. Jupiter's Stunning Southern Hemisphere

See Jupiter's southern hemisphere in beautiful detail in this image taken by our Juno spacecraft. The color-enhanced view captures one of the white ovals in the "String of Pearls," one of eight massive rotating storms at 40 degrees south latitude on the gas giant planet. The image was taken on Oct. 24, 2017, as Juno performed its ninth close flyby of Jupiter. At the time the image was taken, the spacecraft was 20,577 miles (33,115 kilometers) from the tops of the clouds of the planet.

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7. Saturn's Rings: View from Beneath

Our Cassini spacecraft obtained this panoramic view of Saturn's rings on Sept. 9, 2017, just minutes after it passed through the ring plane. The view looks upward at the southern face of the rings from a vantage point above Saturn's southern hemisphere.

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8. From Hot to Hottest

This sequence of images from our Solar Dynamics Observatory shows the Sun from its surface to its upper atmosphere all taken at about the same time (Oct. 27, 2017). The first shows the surface of the sun in filtered white light; the other seven images were taken in different wavelengths of extreme ultraviolet light. Note that each wavelength reveals somewhat different features. They are shown in order of temperature, from the first one at about 11,000 degrees Fahrenheit (6,000 degrees Celsius) on the surface, out to about 10 million degrees in the upper atmosphere. Yes, the sun's outer atmosphere is much, much hotter than the surface. Scientists are getting closer to solving the processes that generate this phenomenon.

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9. High Resolution View of Ceres

This orthographic projection shows dwarf planet Ceres as seen by our Dawn spacecraft. The projection is centered on Occator Crater, home to the brightest area on Ceres. Occator is centered at 20 degrees north latitude, 239 degrees east longitude.

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10. In the Chasm

This image from our Mars Reconnaissance Orbiter shows a small portion of the floor of Coprates Chasma, a large trough within the Valles Marineris system of canyons. Although the exact sequence of events that formed Coprates Chasma is unknown, the ripples, mesas, and craters visible throughout the terrain point to a complex history involving multiple mechanisms of erosion and deposition. The main trough of Coprates Chasma ranges from 37 miles (60 kilometers) to 62 miles (100 kilometers) in width.

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Explore and learn more about our solar system at: solarsystem.nasa.gov/. 

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Are we alone in the universe?

There’s never been a better time to ponder this age-old question. We now know of thousands of exoplanets – planets that orbit stars elsewhere in the universe.

So just how many of these planets could support life?

Scientists from a variety of fields — including astrophysics, Earth science, heliophysics and planetary science — are working on this question. Here are a few of the strategies they’re using to learn more about the habitability of exoplanets.

Squinting at Earth

Even our best telescopic images of exoplanets are still only a few pixels in size. Just how much information can we extract from such limited data? That’s what Earth scientists have been trying to figure out.

One group of scientists has been taking high-resolution images of Earth from our Earth Polychromatic Imaging Camera and ‘degrading’ them in order to match the resolution of our pixelated exoplanet images. From there, they set about a grand process of reverse-engineering: They try to extract as much accurate information as they can from what seems — at first glance — to be a fairly uninformative image.

Credits: NOAA/NASA/DSCOVR

So far, by looking at how Earth’s brightness changes when land versus water is in view, scientists have been able to reverse-engineer Earth's albedo (the proportion of solar radiation it reflects), its obliquity (the tilt of its axis relative to its orbital plane), its rate of rotation, and even differences between the seasons. All of these factors could potentially influence a planet’s ability to support life.

Avoiding the “Venus Zone”

In life as in science, even bad examples can be instructive. When it comes to habitability, Venus is a bad example indeed: With an average surface temperature of 850 degrees Fahrenheit, an atmosphere filled with sulfuric acid, and surface pressure 90 times stronger than Earth’s, Venus is far from friendly to life as we know it.

The surface of Venus, imaged by Soviet spacecraft Venera 13 in March 1982

Since Earth and Venus are so close in size and yet so different in habitability, scientists are studying the signatures that distinguish Earth from Venus as a tool for differentiating habitable planets from their unfriendly look-alikes.

Using data from our Kepler Space Telescope, scientists are working to define the “Venus Zone,” an area where planetary insolation – the amount of light a given planet receives from its host star -- plays a key role in atmospheric erosion and greenhouse gas cycles.

Planets that appear similar to Earth, but are in the Venus Zone of their star, are, we think, unlikely to be able to support life.

Modeling Star-Planet Interactions

When you don’t know one variable in an equation, it can help to plug in a reasonable guess and see how things work out. Scientists used this process to study Proxima b, our closest exoplanet neighbor. We don’t yet know whether Proxima b, which orbits the red dwarf star Proxima Centauri four light-years away, has an atmosphere or a magnetic field like Earth’s. However, we can estimate what would happen if it did.

The scientists started by calculating the radiation emitted by Proxima Centauri based on observations from our Chandra X-ray Observatory. Given that amount of radiation, they estimated how much atmosphere Proxima b would be likely to lose due to ionospheric escape — a process in which the constant outpouring of charged stellar material strips away atmospheric gases.

With the extreme conditions likely to exist at Proxima b, the planet could lose the equivalent of Earth’s entire atmosphere in 100 million years — just a fraction of Proxima b’s 4-billion-year lifetime. Even in the best-case scenario, that much atmospheric mass escapes over 2 billion years. In other words, even if Proxima b did at one point have an atmosphere like Earth, it would likely be long gone by now.

Imagining Mars with a Different Star

We think Mars was once habitable, supporting water and an atmosphere like Earth’s. But over time, it gradually lost its atmosphere – in part because Mars, unlike Earth, doesn’t have a protective magnetic field, so Mars is exposed to much harsher radiation from the Sun's solar wind.

But as another rocky planet at the edge of our solar system’s habitable zone, Mars provides a useful model for a potentially habitable planet. Data from our Mars Atmosphere and Volatile Evolution, or MAVEN, mission is helping scientists answer the question: How would Mars have evolved if it were orbiting a different kind of star?

Scientists used computer simulations with data from MAVEN to model a Mars-like planet orbiting a hypothetical M-type red dwarf star. The habitable zone of such a star is much closer than the one around our Sun.

Being in the habitable zone that much closer to a star has repercussions. In this imaginary situation, the planet would receive about 5 to 10 times more ultraviolet radiation than the real Mars does, speeding up atmospheric escape to much higher rates and shortening the habitable period for the planet by a factor of about 5 to 20.

These results make clear just how delicate a balance needs to exist for life to flourish. But each of these methods provides a valuable new tool in the multi-faceted search for exoplanet life.  Armed with these tools, and bringing to bear a diversity of scientific perspectives, we are better positioned than ever to ask: are we alone?

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Researchers Just Found (For The First Time) An 8th Planet Orbiting A Star Far, Far Away

Our Milky Way galaxy is full of hundreds of billions of worlds just waiting to be found. In 2014, scientists using data from our planet-hunting Kepler space telescope discovered seven planets orbiting Kepler-90, a Sun-like star located 2,500 light-years away. Now, an eighth planet has been identified in this planetary system, making it tied with our own solar system in having the highest number of known planets. Here’s what you need to know:

The new planet is called Kepler-90i.

Kepler-90i is a sizzling hot, rocky planet. It’s the smallest of eight planets in the Kepler-90 system. It orbits so close to its star that a “year” passes in just 14 days.

Average surface temperatures on Kepler-90i are estimated to hover around 800 degrees Fahrenheit, making it an unlikely place for life as we know it.

Its planetary system is like a scrunched up version of our solar system.

The Kepler-90 system is set up like our solar system, with the small planets located close to their star and the big planets farther away. This pattern is evidence that the system’s outer gas planets—which are about the size of Saturn and Jupiter—formed in a way similar to our own.

But the orbits are much more compact. The orbits of all eight planets could fit within the distance of Earth’s orbit around our Sun! Sounds crowded, but think of it this way: It would make for some great planet-hopping.

Kepler-90i was discovered using machine learning.

Most planets beyond our solar system are too far away to be imaged directly. The Kepler space telescope searches for these exoplanets—those planets orbiting stars beyond our solar system—by measuring how the brightness of a star changes when a planet transits, or crosses in front of its disk. Generally speaking, for a given star, the greater the dip in brightness, the bigger the planet!

Researchers trained a computer to learn how to identify the faint signal of transiting exoplanets in Kepler’s vast archive of deep-space data. A search for new worlds around 670 known multiple-planet systems using this machine-learning technique yielded not one, but two discoveries: Kepler-90i and Kepler-80g. The latter is part of a six-planet star system located 1,000 light-years away.

This is just the beginning of a new way of planet hunting.

Kepler-90 is the first known star system besides our own that has eight planets, but scientists say it won’t be the last. Other planets may lurk around stars surveyed by Kepler. Next, researchers are using machine learning with sophisticated computer algorithms to search for more planets around 150,000 stars in the Kepler database.

In the meantime, we’ll be doing more searching with telescopes.

Kepler is the most successful planet-hunting spacecraft to date, with more than 2,500 confirmed exoplanets and many more awaiting verification. Future space missions, like the Transiting Exoplanet Survey Satellite (TESS), the James Webb Space Telescope and Wide-Field Infrared Survey Telescope (WFIRST) will continue the search for new worlds and even tell us which ones might offer promising homes for extraterrestrial life.

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*All images of exoplanets are artist illustrations.

What in the Universe is an Exoplanet?

Simply put, an exoplanet is a planet that orbits another star. 

All of the planets in our solar system orbit around the Sun. Planets that orbit around other stars outside our solar system are called exoplanets.

Just because a planet orbits a star (like Earth) does not mean that it is automatically stable for life. The planet must be within the habitable zone, which is the area around a star in which water has the potential to be liquid…aka not so close that all the water would evaporate, and not too far away where all the water would freeze.

Exoplanets are very hard to see directly with telescopes. They are hidden by the bright glare of the stars they orbit. So, astronomers use other ways to detect and study these distant planets by looking at the effects these planets have on the stars they orbit.

One way to search for exoplanets is to look for "wobbly" stars. A star that has planets doesn’t orbit perfectly around its center. From far away, this off-center orbit makes the star look like it’s wobbling. Hundreds of planets have been discovered using this method. However, only big planets—like Jupiter, or even larger—can be seen this way. Smaller Earth-like planets are much harder to find because they create only small wobbles that are hard to detect.

How can we find Earth-like planets in other solar systems?

In 2009, we launched a spacecraft called Kepler to look for exoplanets. Kepler looked for planets in a wide range of sizes and orbits. And these planets orbited around stars that varied in size and temperature.

Kepler detected exoplanets using something called the transit method. When a planet passes in front of its star, it’s called a transit. As the planet transits in front of the star, it blocks out a little bit of the star's light. That means a star will look a little less bright when the planet passes in front of it. Astronomers can observe how the brightness of the star changes during a transit. This can help them figure out the size of the planet.

By studying the time between transits, astronomers can also find out how far away the planet is from its star. This tells us something about the planet’s temperature. If a planet is just the right temperature, it could contain liquid water—an important ingredient for life.

So far, thousands of planets have been discovered by the Kepler mission.

We now know that exoplanets are very common in the universe. And future missions have been planned to discover many more!

Next month, we’re launching an explorer-class planet finder — the Transiting Exoplanet Survey Satellite (TESS). This mission will search the entire sky for exoplanets — planets outside our solar system that orbit sun-like stars.

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Solar System: Things to Know This Week

Our Juno mission has been exploring Jupiter since July 2016 with a special passenger on board: JunoCam, an instrument designed to take spectacular close-up color images of the largest planet in our solar system. From the raw images, citizen scientists have processed a range of beautiful photographs that highlight Jupiter's features, even turning them into works of art. Below, 10 stunning images JunoCam has given us over the past year.

1. Jovian tempest. 

This color-enhanced image of a massive, raging storm in Jupiter's northern hemisphere was captured by our Juno spacecraft during its ninth close flyby on Oct. 24, 2017. The storm is rotating counter-clockwise with a wide range of cloud altitudes, and the darker clouds are expected to be deeper in the atmosphere than the brightest clouds.

2. A southern stunner. 

Jupiter's southern hemisphere shows off in beautiful detail in this image taken on Oct. 24, 2017. The color-enhanced view captures one of the white ovals in the "String of Pearls," one of eight massive rotating storms at 40 degrees south latitude on the gas giant planet.

3. Dreaming in color. 

Artist Mik Petter created this unique digital piece using data from the JunoCam. The art form, known as fractals, uses mathematical formulas to create an infinite variety of form, detail, color and light. The original JunoCam image was taken on July 10, 2017.

4. Jovian moon shadow. 

Jupiter's moon Amalthea casts a shadow on the gas giant planet in this image taken on Sept. 1, 2017. The elongated shape of the shadow is a result of both the location of the moon with relation to Jupiter in this image as well as the irregular shape of the moon itself.

5. 95 minutes over Jupiter. 

Once every 53 days, Juno swings close to Jupiter, speeding over its clouds. In about two hours, the spacecraft travels from a perch over Jupiter's north pole through its closest approach (perijove), then passes over the south pole on its way back out. This sequence shows 11 color-enhanced images from Perijove 8 (Sept. 1, 2017) with the south pole on the left (11th image in the sequence) and the north pole on the right (first image in the sequence).

6. Soaring high. 

This striking image of Jupiter was taken on Sept. 1, 2017 as Juno performed its eighth flyby. The spacecraft was 4,707 miles (7,576 kilometers) from the tops of the clouds of the planet at a latitude of about -17.4 degrees. Noteworthy: "Whale's Tail" and "Dan's Spot."

7. In true color. 

This true-color image offers a natural color rendition of what the Great Red Spot and surrounding areas would look like to human eyes from Juno's position. The image was taken on July 10, 2017 as the Juno spacecraft performed its seventh close flyby of Jupiter.

8. The 'face' of Jupiter. 

JunoCam images aren't just for art and science—sometimes they're created for a good chuckle. This image, processed by citizen scientist Jason Major, is titled "Jovey McJupiterface." By rotating the image 180 degrees and orienting it from south up, two white oval storms turn into eyeballs, and the "face" of Jupiter is revealed. The original image was taken by the Juno spacecraft on May 19, 2017.

9. Bands of clouds. 

This enhanced-color image of Jupiter's bands of light and dark clouds was created by citizen scientists Gerald Eichstädt and Seán Doran. Three of the white oval storms known as the "String of Pearls" are visible near the top of the image. Each of the alternating light and dark atmospheric bands in this image is wider than Earth, and each rages around Jupiter at hundreds of miles (kilometers) per hour. The lighter areas are regions where gas is rising, and the darker bands are regions where gas is sinking. Juno captured the image on May 19, 2017.

10. The edge. 

This enhanced-color image of a mysterious dark spot on Jupiter seems to reveal a Jovian "galaxy" of swirling storms. Juno captured this image on Feb. 2, 2017 and citizen scientist Roman Tkachenko enhanced the color to bring out the rich detail in the storm and surrounding clouds. Just south of the dark storm is a bright, oval-shaped storm with high, bright, white clouds, reminiscent of a swirling galaxy. As a final touch, he rotated the image 90 degrees, turning the picture into a work of art.

To learn more about the Juno mission at Jupiter, visit: www.nasa.gov/juno. 

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Solar System: 10 Things to Know This Week

Even the most ambitious plans start with a drawing. Visualizing a distant destination or an ambitious dream is the first step to getting there. For decades, artists working on NASA projects have produced beautiful images that stimulated the imaginations of the people working to make them a reality. 

Some of them offered visualizations of spacecraft that had not yet been built; others imagined what it might look like to stand on planets that had not yet been explored. This week, we look at 10 pieces of conceptual art for our missions before they were launched–along with actual photos taken when those missions arrived at their destinations.

1. Apollo at the Moon

In 1968, an artist with our contractor North American Rockwell illustrated a phase of the Apollo lunar missions, showing the Command and Service Modules over the surface of the Moon. In 1971, an astronaut aboard the Lunar Module during Apollo 15 captured a similar scene in person with a camera.

2. Ready for Landing

This artist’s concept depicts an Apollo Lunar Module firing its descent engine above the lunar surface. At right, a photo from Apollo 12 in 1969 showing the Lunar Module Intrepid, taken by Command Module Pilot Richard Gordon.

3. Man and Machine on the Moon

Carlos Lopez, an artist with Hughes Aircraft Company, created a preview of a Surveyor spacecraft landing for our Jet Propulsion Laboratory in the early 1960s. The robotic Surveyor missions soft landed on the Moon, collecting data and images of the surface in order to ensure a safe arrival for Apollo astronauts a few years later. In the image at right, Apollo 12 astronaut Alan Bean examines the Surveyor 3 spacecraft during his second excursion on the Moon in November 1969.

4. O Pioneer!

In missions that lived up to their names, we sent the Pioneer 10 and 11 spacecraft to perform the first up-close exploration of the outer solar system. At left, an artist’s imagining of Pioneer passing Jupiter. At right, Pioneer 11’s real view of the king of planets taken in 1974.

5. The Grand Tour

An even more ambitious pair of robotic deep space adventurers followed the Pioneers. Voyager 1 and 2 both visited Jupiter and Saturn. Voyager 2 went on to Uranus and Neptune. Even the most visionary artists couldn’t imagine the exotic and beautiful vistas that the Voyager spacecraft witnessed. These images were taken between 1979 and 1989.

6. Journey to a Giant

Our Cassini spacecraft carried a passenger to the Saturn system: the European Space Agency’s Huygens probe. Huygens was designed to land on Saturn’s planet-sized moon Titan. At left is an artist’s view of Cassini sending the Huygens probe on its way toward Titan, and at right are some actual images of the giant moon from Cassini’s cameras.

7. Titan Unveiled

On Jan. 14, 2005, the Huygens probe descended through Titan’s thick haze and revealed what Titan’s surface looks like for the first time in history. Before the landing, an artist imagined the landscape (left). During the descent, Huygens’ imagers captured the actual view at four different altitudes (center)—look for the channels formed by rivers of liquid hyrdocarbons. Finally, the probe came to rest on a pebble-strewn plain (right).

8. Hazy Skies over Pluto

David Seal rendered this imaginary view from the surface of Pluto, and in the sky above, an early version of the spacecraft that came to be known as our New Horizons. At the time, Pluto was already suspected of having a thin atmosphere. That turned out be true, as seen in this dramatic backlit view of Pluto’s hazy, mountainous horizon captured by one of New Horizons’ cameras in 2015.

9. Dreams on Mars, Wheels on Mars

Long before it landed in Gale Crater, our Curiosity rover was the subject of several artistic imaginings during the years the mission was in development. Now that Curiosity is actually rolling through the Martian desert, it occasionally stops to take a self-portrait with the camera at the end of its robotic arm, which it uses like a selfie stick.

10. The World, Ceres

No one knew exactly what the dwarf planet Ceres, the largest body in the asteroid belt, looked like until our Dawn mission got there. Dawn saw a heavily cratered world—with a few surprises, such as the famous bright spots in Occator crater.

There’s more to come. Today we have carefully created artist impressions of several unexplored destinations in the solar system, including the asteroids Psyche and Bennu, and an object one billion miles past Pluto that’s now called 2014 MU69. 

You can help nickname this object (or objects—there may be two) by submitting your names by Dec. 1. Our New Horizons spacecraft will fly past MU69 on New Year’s Day 2019.

Soon, we’ll once again see how nature compares to our imaginations. It’s almost always stranger and more beautiful than we thought.

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Solar System: 10 Things to Know This Week...Halloween Edition!

This week, we're getting into the Halloween spirit with 10 spooktacular things to let your imagination run wild. 

It's not Halloween without our favorite scary characters, but what if they could stop bothering us Earthlings and go far, far away? We begin with where Dracula, Frankenstein, and other creepy creatures might choose to live if the galaxy were theirs to claim...

1. The dark (k)night.

The prince of darkness himself, Dracula, can finally seek sweet respite from the Sun. We think he'd love to live on a rocky planet named YZ Ceti d that orbits so close to its red star that it's tidally locked keeping one side of the planet in perpetual nighttime and the other side in perpetual daytime, with a brilliant red sky (though we can guess which side Dracula will prefer). 

2. Where art thou, werewolves? 

Home sweet home for our furry Full Moon friends might just be on Trappist-1, a planetary system with seven planets—and where standing on one planet would mean the other planets look like six moons (some as big as our Moon in the sky). 

3. Left in the dust. 

We couldn't think of anyone better to live on Proxima b than The Mummy. Hopefully this ancient monster can finally rest in peace on an exoplanet that scientists theorize is a desert planet once home to ancient oceans. 

4. Cloudy with a chance of Frankenstein.

One scientific experiment we'd like to conduct: whether Frankenstein would rather live on HAT-P-11b or Kepler-3b, theorized to have fierce thunderstorms and lightning. 

5. The walking dead. 

We're pretty confident that if zombies were to pick a planet, they'd want one that shares their love of death and destruction. We think they'd feel right at home on one of the pulsar planets, which are scorched by radiation because they orbit a dead star. 

6. Rest your weary bones. 

Skeletons need look no further: Osiris, an exoplanet that's so close to a star that it's "losing its flesh" as the star destroys it, seems like a perfect match. 

7. Enough of the scary stuff. 

For kids out there, turn pumpkin decorating into an out-of-this-world activity with space-themed stencils, from Saturn to the Sun. 

8. Spooky sounds. 

Cassini's radio emissions from Saturn could give creaky doors and howling winds a run for their money. Listen to the eerie audio recordings here and find more HERE.

9. Pumpkin-carve like a NASA engineer. 

NASA engineers design and build robots that can fly millions of miles to study other planets for a living—so on Halloween, they can't help but bring that creative thinking to the grand old tradition of pumpkin carving. Take a cue from their creations with these insider tips.

10. Detective for a day. 

From blades of ice on Pluto to a fuzzy, white "bunny" photographed on Mars, become a solar system sleuth and see if you can solve the stellar mysteries in this slideshow (then compare with how scientists cracked the case). 

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Taking the Vital Signs of Mars

Does Mars have quakes? What is the temperature of the Red Planet? How did Mars even form? What can it tell us about how other rocky planets formed?

The Mars InSight lander is scheduled to launch in May 2018 to search for the answers to those questions.

InSight (Interior Exploration using Seismic Investigations, Geodesy and Heat Transport) will conduct the first thorough “check-up” of Mars in more than 4.5 billion years, measuring its “pulse”, or seismic activity; its temperature; and its “reflexes” (the way the planet wobbles when it is pulled by the Sun and its moons).

How and Why?

By using sophisticated instruments – tools that can measure the vital signs of a planet – InSight will delve deep beneath the surface of Mars, detecting the clues left by the earliest stages of planetary formation.  

Previous Mars missions have explored the surface history of the Red Planet. Mars has been less geologically active than Earth, so it retains a more complete record of its history in its core, mantle and crust. InSight will study the sizes, densities and overall structure of the Red Planet’s core, mantle and crust. 

The lander will also measure the rate at which heat escapes from the planet’s interior, and provide glimpses into the evolutionary processes of all the rocky planets in our solar system, including Earth, and even those circling other stars!

Send Your Name to Mars!

You can send your name to Mars onboard the InSight lander! The deadline to get your Martian boarding pass is Nov. 1. To submit your name, visit: mars.nasa.gov/syn/insight

Learn more about Mars InSight HERE.

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Chasing the Shadow of Neptune’s Moon Triton

Our Flying Observatory

Our flying observatory, called SOFIA, carries a 100-inch telescope inside a Boeing 747SP aircraft. Scientists onboard study the life cycle of stars, planets (including the atmosphere of Mars and Jupiter), nearby planetary systems, galaxies, black holes and complex molecules in space.

AND on Oct. 5, SOFIA is going on a special flight to chase the shadow of Neptune's moon Triton as it crosses Earth’s surface!

In case you’re wondering, SOFIA stands for: Stratospheric Observatory for Infrared Astronomy.

Triton

Triton is 1,680 miles (2,700 km) across, making it the largest of the 13 moons orbiting Neptune. Unlike most large moons in our solar system, Triton orbits in the opposite direction of Neptune, called a retrograde orbit. This backward orbit leads scientists to believe that Triton formed in an area past Neptune, called the Kuiper Belt, and was pulled into its orbit around Neptune by gravity. 

The Voyager 2 spacecraft flew past Neptune and Triton in 1989 and found that Triton’s atmosphere is made up of mostly nitrogen...but it has not been studied in nearly 16 years!

Occultations are Eclipse-Like Events

An occultation occurs when an object, like a planet or a moon, passes in front of a star and completely blocks the light from that star. As the object blocks the star’s light, it casts a faint shadow on Earth’s surface. 

But unlike an eclipse, these shadows are not usually visible to the naked eye because the star and object are much smaller and not nearly as bright as our sun. Telescopes with special instruments can actually see these shadows and study the star’s light as it passes near and around the object – if they can be in the right place on Earth to catch the shadow.

Chasing Shadows

Scientists have been making advanced observations of Triton and a background star. They've calculated exactly where Triton’s faint shadow will fall on Earth! Our SOFIA team has designed a flight path that will put SOFIA (the telescope and aircraft) exactly in the center of the shadow at the precise moment that Triton and the star will align. 

This is no easy feat because the shadow is moving at more than 53,000 mph while SOFIA flies at Mach 0.85 (652 mph), so we only have about two minutes to catch the shadow!! But our SOFIA team has previously harnessed the aircraft’s mobility to study Pluto from inside the center of its occultation shadow, and is ready to do it again to study Triton!

What We Learn From Inside the Shadow

From inside the shadow, our team on SOFIA will study the star’s light as it passes around and through Triton’s atmosphere. This allows us to learn more about Triton’s atmosphere, including its temperature, pressure, density and composition! 

Our team will use this information to examine if Triton’s atmosphere has changed since our Voyager 2 spacecraft flew past it in 1989. That’s a lot of information from a bit of light inside a shadow! Similar observations of Uranus in 1977, from our previous flying observatory, led to the discovery of rings around that planet!

International Ground-Based Support

Ground-based telescopes across the United States and Europe – from Scotland to the Canary Islands – will also be studying Triton’s occultation. Even though most of these telescopes will not be in the center of the shadow, the simultaneous observations, from different locations on Earth, will give us information about how Triton’s atmosphere varies across its latitudes. 

This data from across the Earth and from onboard SOFIA will help researchers understand how Triton’s atmosphere is distorted at different locations by its high winds and its strong tides!

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Cassini Mission: What’s Next?

It’s Friday, Sept. 15 and our Cassini mission has officially come to a spectacular end. The final signal from the spacecraft was received here on Earth at 7:55 a.m. EDT after a fateful plunge into Saturn’s atmosphere.

After losing contact with Earth, the spacecraft burned up like a meteor, becoming part of the planet itself.

Although bittersweet, Cassini’s triumphant end is the culmination of a nearly 20-year mission that overflowed with discoveries.

But, what happens now?

Mission Team and Data

Now that the spacecraft is gone, most of the team’s engineers are migrating to other planetary missions, where they will continue to contribute to the work we’re doing to explore our solar system and beyond.

Mission scientists will keep working for the coming years to ensure that we fully understand all of the data acquired during the mission’s Grand Finale. They will carefully calibrate and study all of this data so that it can be entered into the Planetary Data System. From there, it will be accessible to future scientists for years to come.

Even beyond that, the science data will continue to be worked on for decades, possibly more, depending on the research grants that are acquired.

Other team members, some who have spent most of their career working on the Cassini mission, will use this as an opportunity to retire.

Future Missions

In revealing that Enceladus has essentially all the ingredients needed for life, the mission energized a pivot to the exploration of “ocean worlds” that has been sweeping planetary science over the past couple of decades.

Jupiter’s moon Europa has been a prime target for future exploration, and many lessons during Cassini’s mission are being applied in planning our Europa Clipper mission, planned for launch in the 2020s.

The mission will orbit the giant planet, Jupiter, using gravitational assists from large moons to maneuver the spacecraft into repeated close encounters, much as Cassini has used the gravity of Titan to continually shape the spacecraft’s course.

In addition, many engineers and scientists from Cassini are serving on the new Europa Clipper mission and helping to shape its science investigations. For example, several members of the Cassini Ion and Neutral Mass Spectrometer team are developing an extremely sensitive, next-generation version of their instrument for flight on Europa Clipper. What Cassini has learned about flying through the plume of material spraying from Enceladus will be invaluable to Europa Clipper, should plume activity be confirmed on Europa.

In the decades following Cassini, scientists hope to return to the Saturn system to follow up on the mission's many discoveries. Mission concepts under consideration include robotic explorers to drift on the methane seas of Titan and fly through the Enceladus plume to collect and analyze samples for signs of biology.

Atmospheric probes to all four of the outer planets have long been a priority for the science community, and the most recent recommendations from a group of planetary scientists shows interest in sending such a mission to Saturn. By directly sampling Saturn's upper atmosphere during its last orbits and final plunge, Cassini is laying the groundwork for an potential Saturn atmospheric probe.

A variety of potential mission concepts are discussed in a recently completed study — including orbiters, flybys and probes that would dive into Uranus' atmosphere to study its composition. Future missions to the ice giants might explore those worlds using an approach similar to Cassini's mission.

Learn more about the Cassini mission and its Grand Finale HERE.

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Cassini Spacecraft: Top Discoveries

Our Cassini spacecraft has been exploring Saturn, its stunning rings and its strange and beautiful moons for more than a decade.

Having expended almost every bit of the rocket propellant it carried to Saturn, operators are deliberately plunging Cassini into the planet to ensure Saturn’s moons will remain pristine for future exploration – in particular, the ice-covered, ocean-bearing moon Enceladus, but also Titan, with its intriguing pre-biotic chemistry.

Let’s take a look back at some of Cassini’s top discoveries:  

Titan

Under its shroud of haze, Saturn’s planet-sized moon Titan hides dunes, mountains of water ice and rivers and seas of liquid methane. Of the hundreds of moons in our solar system, Titan is the only one with a dense atmosphere and large liquid reservoirs on its surface, making it in some ways more like a terrestrial planet.

Both Earth and Titan have nitrogen-dominated atmospheres – over 95% nitrogen in Titan’s case. However, unlike Earth, Titan has very little oxygen; the rest of the atmosphere is mostly methane and traced amounts of other gases, including ethane.

There are three large seas, all located close to the moon’s north pole, surrounded by numerous smaller lakes in the northern hemisphere. Just one large lake has been found in the southern hemisphere.

Enceladus

The moon Enceladus conceals a global ocean of salty liquid water beneath its icy surface. Some of that water even shoots out into space, creating an immense plume!

For decades, scientists didn’t know why Enceladus was the brightest world in the solar system, or how it related to Saturn’s E ring. Cassini found that both the fresh coating on its surface, and icy material in the E ring originate from vents connected to a global subsurface saltwater ocean that might host hydrothermal vents.

With its global ocean, unique chemistry and internal heat, Enceladus has become a promising lead in our search for worlds where life could exist.

Iapetus

Saturn’s two-toned moon Iapetus gets its odd coloring from reddish dust in its orbital path that is swept up and lands on the leading face of the moon.

The most unique, and perhaps most remarkable feature discovered on Iapetus in Cassini images is a topographic ridge that coincides almost exactly with the geographic equator. The physical origin of the ridge has yet to be explained...

It is not yet year whether the ridge is a mountain belt that has folded upward, or an extensional crack in the surface through which material from inside Iapetus erupted onto the surface and accumulated locally.

Saturn’s Rings

Saturn’s rings are made of countless particles of ice and dust, which Saturn’s moons push and tug, creating gaps and waves.

Scientists have never before studied the size, temperature, composition and distribution of Saturn’s rings from Saturn obit. Cassini has captured extraordinary ring-moon interactions, observed the lowest ring-temperature ever recorded at Saturn, discovered that the moon Enceladus is the source for Saturn’s E ring, and viewed the rings at equinox when sunlight strikes the rings edge-on, revealing never-before-seen ring features and details.

Cassini also studied features in Saturn’s rings called “spokes,” which can be longer than the diameter of Earth. Scientists think they’re made of thin icy particles that are lifted by an electrostatic charge and only last a few hours.  

Auroras

The powerful magnetic field that permeates Saturn is strange because it lines up with the planet’s poles. But just like Earth’s field, it all creates shimmering auroras.

Auroras on Saturn occur in a process similar to Earth’s northern and southern lights. Particles from the solar wind are channeled by Saturn’s magnetic field toward the planet’s poles, where they interact with electrically charged gas (plasma) in the upper atmosphere and emit light.  

Turbulent Atmosphere

Saturn’s turbulent atmosphere churns with immense storms and a striking, six-sided jet stream near its north pole.

Saturn’s north and south poles are also each beautifully (and violently) decorated by a colossal swirling storm. Cassini got an up-close look at the north polar storm and scientists found that the storm’s eye was about 50 times wider than an Earth hurricane’s eye.

Unlike the Earth hurricanes that are driven by warm ocean waters, Saturn’s polar vortexes aren’t actually hurricanes. They’re hurricane-like though, and even contain lightning. Cassini’s instruments have ‘heard’ lightning ever since entering Saturn orbit in 2004, in the form of radio waves. But it wasn’t until 2009 that Cassini’s cameras captured images of Saturnian lighting for the first time.

Cassini scientists assembled a short video of it, the first video of lightning discharging on a planet other than Earth.

Cassini’s adventure will end soon because it’s almost out of fuel. So to avoid possibly ever contaminating moons like Enceladus or Titan, on Sept. 15 it will intentionally dive into Saturn’s atmosphere.

The spacecraft is expected to lose radio contact with Earth within about one to two minutes after beginning its decent into Saturn’s upper atmosphere. But on the way down, before contact is lost, eight of Cassini’s 12 science instruments will be operating! More details on the spacecraft’s final decent can be found HERE.

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Planets: As Seen by Voyager

The Voyager 1 and 2 spacecraft explored Jupiter, Saturn, Uranus and Neptune before starting their journey toward interstellar space. Here you’ll find some of those images, including “The Pale Blue Dot” – famously described by Carl Sagan – and what are still the only up-close images of Uranus and Neptune.

These twin spacecraft took some of the very first close-up images of these planets and paved the way for future planetary missions to return, like the Juno spacecraft at Jupiter, Cassini at Saturn and New Horizons at Pluto.

Jupiter

Photography of Jupiter began in January 1979, when images of the brightly banded planet already exceeded the best taken from Earth. They took more than 33,000 pictures of Jupiter and its five major satellites. 

Findings:

Erupting volcanoes on Jupiter's moon Io, which has 100 times the volcanic activity of Earth. 

Better understanding of important physical, geological, and atmospheric processes happening in the planet, its satellites and magnetosphere.

Jupiter's turbulent atmosphere with dozens of interacting hurricane-like storm systems.

Saturn

The Saturn encounters occurred nine months apart, in November 1980 and August 1981. The two encounters increased our knowledge and altered our understanding of Saturn. The extended, close-range observations provided high-resolution data far different from the picture assembled during centuries of Earth-based studies.

Findings:

Saturn’s atmosphere is almost entirely hydrogen and helium.

Subdued contrasts and color differences on Saturn could be a result of more horizontal mixing or less production of localized colors than in Jupiter’s atmosphere.

An indication of an ocean beneath the cracked, icy crust of Jupiter's moon Europa. 

Winds blow at high speeds in Saturn. Near the equator, the Voyagers measured winds about 1,100 miles an hour.

Uranus

The Voyager 2 spacecraft flew closely past distant Uranus, the seventh planet from the Sun. At its closest, the spacecraft came within 50,600 miles of Uranus’s cloud tops on Jan. 24, 1986. Voyager 2 radioed thousands of images and voluminous amounts of other scientific data on the planet, its moons, rings, atmosphere, interior and the magnetic environment surrounding Uranus.

Findings:

Revealed complex surfaces indicative of varying geologic pasts.

Detected 11 previously unseen moons.

Uncovered the fine detail of the previously known rings and two newly detected rings.

Showed that the planet’s rate of rotation is 17 hours, 14 minutes.

Found that the planet’s magnetic field is both large and unusual.

Determined that the temperature of the equatorial region, which receives less sunlight over a Uranian year, is nevertheless about the same as that at the poles.

Neptune

Voyager 2 became the first spacecraft to observe the planet Neptune in the summer of 1989. Passing about 3,000 miles above Neptune’s north pole, Voyager 2 made its closest approach to any planet since leaving Earth 12 years ago. Five hours later, Voyager 2 passed about 25,000 miles from Neptune’s largest moon, Triton, the last solid body the spacecraft had the opportunity to study.

Findings: 

Discovered Neptune’s Great Dark Spot

Found that the planet has strong winds, around 1,000 miles per hour

Saw geysers erupting from the polar cap on Neptune’s moon Triton at -390 degrees Fahrenheit

Solar System Portrait

This narrow-angle color image of the Earth, dubbed ‘Pale Blue Dot’, is a part of the first ever ‘portrait’ of the solar system taken by Voyager 1. 

The spacecraft acquired a total of 60 frames for a mosaic of the solar system from a distance of more than 4 billion miles from Earth and about 32 degrees above the ecliptic.

From Voyager’s great distance, Earth is a mere point of light, less than the size of a picture element even in the narrow-angle camera.

“Look again at that dot. That's here. That's home. That's us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives.” - Carl Sagan

Both spacecraft will continue to study ultraviolet sources among the stars, and their fields and particles detectors will continue to search for the boundary between the Sun's influence and interstellar space. The radioisotope power systems will likely provide enough power for science to continue through 2025, and possibly support engineering data return through the mid-2030s. After that, the two Voyagers will continue to orbit the center of the Milky Way.

Learn more about the Voyager spacecraft HERE.

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Magnetospheres: How Do They Work?

The sun, Earth, and many other planets are surrounded by giant magnetic bubbles.

Space may seem empty, but it’s actually a dynamic place, dominated by invisible forces, including those created by magnetic fields.  Magnetospheres – the areas around planets and stars dominated by their magnetic fields – are found throughout our solar system. They deflect high-energy, charged particles called cosmic rays that are mostly spewed out by the sun, but can also come from interstellar space. Along with atmospheres, they help protect the planets’ surfaces from this harmful radiation.

It’s possible that Earth’s protective magnetosphere was essential for the development of conditions friendly to life, so finding magnetospheres around other planets is a big step toward determining if they could support life.

But not all magnetospheres are created equal – even in our own backyard, not all planets in our solar system have a magnetic field, and the ones we have observed are all surprisingly different.

Earth’s magnetosphere is created by the constantly moving molten metal inside Earth. This invisible “force field” around our planet has an ice cream cone-like shape, with a rounded front and a long, trailing tail that faces away from the sun. The magnetosphere is shaped that way because of the constant pressure from the solar wind and magnetic fields on the sun-facing side.

Earth’s magnetosphere deflects most charged particles away from our planet – but some do become trapped in the magnetic field and create auroras when they rain down into the atmosphere.

We have several missions that study Earth’s magnetosphere – including the Magnetospheric Multiscale mission, Van Allen Probes, and Time History of Events and Macroscale Interactions during Substorms (also known as THEMIS) – along with a host of other satellites that study other aspects of the sun-Earth connection.

Mercury, with a substantial iron-rich core, has a magnetic field that is only about 1% as strong as Earth’s. It is thought that the planet’s magnetosphere is stifled by the intense solar wind, limiting its strength, although even without this effect, it still would not be as strong as Earth’s. The MESSENGER satellite orbited Mercury from 2011 to 2015, helping us understand our tiny terrestrial neighbor.

After the sun, Jupiter has by far the biggest magnetosphere in our solar system – it stretches about 12 million miles from east to west, almost 15 times the width of the sun. (Earth’s, on the other hand, could easily fit inside the sun.) Jupiter does not have a molten metal core like Earth; instead, its magnetic field is created by a core of compressed liquid metallic hydrogen.

One of Jupiter’s moons, Io, has intense volcanic activity that spews particles into Jupiter’s magnetosphere. These particles create intense radiation belts and the large auroras around Jupiter’s poles.

Ganymede, Jupiter’s largest moon, also has its own magnetic field and magnetosphere – making it the only moon with one. Its weak field, nestled in Jupiter’s enormous shell, scarcely ruffles the planet’s magnetic field.

Our Juno mission orbits inside the Jovian magnetosphere sending back observations so we can better understand this region. Previous observations have been received from Pioneers 10 and 11, Voyagers 1 and 2, Ulysses, Galileo and Cassini in their flybys and orbits around Jupiter.

Saturn’s moon Enceladus transforms the shape of its magnetosphere. Active geysers on the moon’s south pole eject oxygen and water molecules into the space around the planet. These particles, much like Io’s volcanic emissions at Jupiter, generate the auroras around the planet’s poles. Our Cassini mission studies Saturn’s magnetic field and auroras, as well as its moon Enceladus.

Uranus’ magnetosphere wasn't discovered until 1986 when data from Voyager 2’s flyby revealed weak, variable radio emissions. Uranus’ magnetic field and rotation axis are out of alignment by 59 degrees, unlike Earth’s, whose magnetic field and rotation axis differ by only 11 degrees. On top of that, the magnetic field axis does not go through the center of the planet, so the strength of the magnetic field varies dramatically across the surface. This misalignment also means that Uranus’ magnetotail – the part of the magnetosphere that trails away from the sun – is twisted into a long corkscrew.

Neptune’s magnetosphere is also tilted from its rotation axis, but only by 47. Just like on Uranus, Neptune’s magnetic field strength varies across the planet. This also means that auroras can be seen away from the planet’s poles – not just at high latitudes, like on Earth, Jupiter and Saturn.

Does Every Planet Have a Magnetosphere?

Neither Venus nor Mars have global magnetic fields, although the interaction of the solar wind with their atmospheres does produce what scientists call an “induced magnetosphere.” Around these planets, the atmosphere deflects the solar wind particles, causing the solar wind’s magnetic field to wrap around the planet in a shape similar to Earth’s magnetosphere.

What About Beyond Our Solar System?

Outside of our solar system, auroras, which indicate the presence of a magnetosphere, have been spotted on brown dwarfs – objects that are bigger than planets but smaller than stars.

There’s also evidence to suggest that some giant exoplanets have magnetospheres. As scientists now believe that Earth’s protective magnetosphere was essential for the development of conditions friendly to life, finding magnetospheres around exoplanets is a big step in finding habitable worlds.  

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