Ceres - Blog Posts

Greatest Hits — Craters We Love

Our solar system was built on impacts — some big, some small — some fast, some slow. This week, in honor of a possible newly-discovered large crater here on Earth, here’s a quick run through of some of the more intriguing impacts across our solar system.

1. Mercury: A Basin Bigger Than Texas

Mercury does not have a thick atmosphere to protect it from space debris. The small planet is riddled with craters, but none as spectacular as the Caloris Basin. “Basin” is what geologists call craters larger than about 186 miles (300 kilometers) in diameter. Caloris is about 950 miles (1,525 kilometers) across and is ringed by mile-high mountains.

For scale, the state of Texas is 773 miles (1,244 kilometers) wide from east to west.

2. Venus: Tough on Space Rocks

Venus’ ultra-thick atmosphere finishes off most meteors before they reach the surface. The planet’s volcanic history has erased many of its craters, but like almost any place with solid ground in our solar system, there are still impact scars to be found. Most of what we know of Venus’ craters comes from radar images provided by orbiting spacecraft, such as NASA’s Magellan.

Mead Crater is the largest known impact site on Venus. It is about 170 miles (275 kilometers) in diameter. The relatively-flat, brighter inner floor of the crater indicates it was filled with impact melt and/or lava.

3. Earth: Still Craters After All These Years

Evidence of really big impacts — such as Arizona’s Meteor Crater — are harder to find on Earth. The impact history of our home world has largely been erased by weather and water or buried under lava, rock or ice. Nonetheless, we still find new giant craters occasionally.

A NASA glaciologist has discovered a possible impact crater buried under more than a mile of ice in northwest Greenland.

This follows the finding, announced in November 2018, of a 19-mile (31-kilometer) wide crater beneath Hiawatha Glacier – the first meteorite impact crater ever discovered under Earth’s ice sheets. 

If the second crater, which has a width of over 22 miles (35 kilometers), is ultimately confirmed as the result of a meteorite impact, it will be the 22nd largest impact crater found on Earth.

4. Moon: Our Cratered Companion

Want to imagine what Earth might look like without its protective atmosphere, weather, water and other crater-erasing features? Look up at the Moon. The Moon’s pockmarked face offers what may be humanity’s most familiar view of impact craters.

One of the easiest to spot is Tycho, the tight circle and bright, radiating splat are easy slightly off center on the lower-left side of the full moon. Closer views of the 53-mile (85 kilometer)-wide crater from orbiting spacecraft reveal a beautiful central peak, topped with an intriguing boulder that would fill about half of a typical city block.

5. Mars: Still Taking Hits

Mars has just enough atmosphere to ensure nail-biting spacecraft landings, but not enough to prevent regular hits from falling space rocks. This dark splat on the Martian south pole is less than a year old, having formed between July and September 2018. The two-toned blast pattern tells a geologic story. The larger, lighter-colored blast pattern could be the result of scouring by winds from the impact shockwave on ice. The darker-colored inner blast pattern is because the impactor penetrated the thin ice layer, blasting the dark sand underneath in all directions.

6. Ceres: What Lies Beneath

The bright spots in Ceres’ Occator crater intrigued the world from the moment the approaching Dawn spacecraft first photographed it in 2015. Closer inspection from orbit revealed the spots to be the most visible example of hundreds of bright, salty deposits that decorate the dwarf planet like a smattering of diamonds. The science behind these bright spots is even more compelling: they are mainly sodium carbonate and ammonium chloride that somehow made their way to the surface in a slushy brine from within or below the crust. Thanks to Dawn, scientists have a better sense of how these reflective areas formed and changed over time — processes indicative of an active, evolving world.

7. Comet Tempel 1: We Did It!

Scientists have long known we can learn a lot from impact craters — so, in 2005, they made one themselves and watched it happen.

On July 4, 2005, NASA’s Deep Impact spacecraft trained its instruments on an 816-pound (370-kilogram) copper impactor as it smashed into comet Tempel 1.

One of the more surprising findings: The comet has a loose, “fluffy” structure, held together by gravity and contains a surprising amount of organic compounds that are part of the basic building blocks of life.

8. Mimas: May the 4th Be With You

Few Star Wars fans — us included — can resist Obi Wan Kenobi's memorable line “That’s no moon…” when images of Saturn’s moon Mimas pop up on a screen. Despite its Death Star-like appearance, Mimas is most definitely a moon. Our Cassini spacecraft checked, a lot — and the superlaser-looking depression is simply an 81-mile (130-kilometer) wide crater named for the moon’s discoverer, William Herschel.

9. Europa: Say What?

The Welsh name of this crater on Jupiter’s ocean moon Europa looks like a tongue-twister, but it is easiest pronounced as “pool.” Pwyll is thought to be one of the youngest features we know of on Europa. The bright splat from the impact extends more than 600 miles (about 1,000 kilometers) around the crater, a fresh blanket over rugged, older terrain. “Fresh,” or young, is a relative term in geology; the crater and its rays are likely millions of years old.

10. Show Us Your Greatest Hits

Got a passion for Stickney, the dominant bowl-shaped crater on one end of Mars’ moon Phobos? Or a fondness for the sponge-like abundance of impacts on Saturn’s battered moon Hyperion (pictured)? There are countless craters to choose from. Share your favorites with us on Twitter, Instagram and Facebook.

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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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Solar System: 10 Things to Know This Week

Every day, our spacecraft and people are exploring the solar system. Both the public and the private sectors are contributing to the quest. For example, here are ten things happening just this week:

1. We deliver. 

The commercial space company Orbital ATK is targeting Saturday, Nov. 11 for the launch of its Cygnus spacecraft on an Antares rocket from Wallops Flight Facility in Wallops Island, Virginia. Cygnus is launching on a resupply mission to the International Space Station, carrying cargo and scientific experiments to the six people currently living on the microgravity laboratory. 

2. See for yourself. 

Social media users are invited to register to attend another launch in person, this one of a SpaceX Falcon 9 rocket carrying the Dragon spacecraft from Cape Canaveral Air Force Station in Florida. This launch, currently targeted for no earlier than December, will be the next commercial cargo resupply mission to the International Space Station. The deadline to apply is Nov. 7. Apply HERE.

3. Who doesn't like to gaze at the Moon?

Our Lunar Reconnaissance Orbiter (LRO) sure does—and from very close range. This robotic spacecraft has been orbiting Earth's companion since 2009, returning views of the lunar surface that are so sharp they show the footpaths made by Apollo astronauts. Learn more about LRO and the entire history of lunar exploration at NASA's newly-updated, expanded Moon site: moon.nasa.gov

4. Meanwhile at Mars...

Another sharp-eyed robotic spacecraft has just delivered a fresh batch of equally detailed images. Our Mars Reconnaissance Orbiter (MRO) surveys the Red Planet's surface daily, and you can see the very latest pictures of those exotic landscapes HERE. We currently operate five—count 'em, five—active missions at Mars, with another (the InSight lander) launching next year. Track them all at: mars.nasa.gov.

5. Always curious. 

One of those missions is the Curiosity rover. It's currently climbing a rocky highland dubbed Vera Rubin Ridge, turning its full array of instruments on the intriguing geology there. Using those instruments, Curiosity can see things you and I can't.

6. A new Dawn. 

Our voyage to the asteroid belt has a new lease on life. The Dawn spacecraft recently received a mission extension to continue exploring the dwarf planet Ceres. This is exciting because minerals containing water are widespread on Ceres, suggesting it may have had a global ocean in the past. What became of that ocean? Could Ceres still have liquid today? Ongoing studies from Dawn could shed light on these questions.

7. There are eyes everywhere. 

When our Mars Pathfinder touched down in 1997, it had five cameras: two on a mast that popped up from the lander, and three on the rover, Sojourner. Since then, photo sensors that were improved by the space program have shrunk in size, increased in quality and are now carried in every cellphone. That same evolution has returned to space. Our Mars 2020 mission will have more "eyes" than any rover before it: a grand total of 23, to create sweeping panoramas, reveal obstacles, study the atmosphere, and assist science instruments.

8. Voyage to a hidden ocean.

One of the most intriguing destinations in the solar system is Jupiter's moon Europa, which hides a global ocean of liquid water beneath its icy shell. Our Europa Clipper mission sets sail in the 2020s to take a closer look than we've ever had before. You can explore Europa, too: europa.nasa.gov

9. Flight of the mockingbird. 

On Nov. 10, the main belt asteroid 19482 Harperlee, named for the legendary author of To Kill a Mockingbird, makes its closest approach to Earth during the asteroid's orbit around the Sun. Details HERE. Learn more about asteroids HERE. Meanwhile, our OSIRIS-REx mission is now cruising toward another tiny, rocky world called Bennu.

10. What else is up this month? 

For sky watchers, there will be a pre-dawn pairing of Jupiter and Venus, the Moon will shine near some star clusters, and there will be meteor activity all month long. Catch our monthly video blog for stargazers HERE.

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Solar System: 10 Things to Know This Week

Need some space? 

Here are 10 perspective-building images for your computer desktop and mobile device wallpaper. 

These are all real images, sent very recently by our planetary missions throughout the solar system. 

1. Our Sun

Warm up with this view from our Solar Dynamics Observatory showing active regions on the Sun in October 2017. They were observed in a wavelength of extreme ultraviolet light that reveals plasma heated to over a million degrees. 

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2. Jupiter Up-Close

This series of enhanced-color images shows Jupiter up close and personal, as our Juno spacecraft performed its eighth flyby of the gas giant planet on Sept. 1, 2017. 

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3. Saturn’s and Its Rings

With this mosaic from Oct. 28, 2016, our Cassini spacecraft captured one of its last looks at Saturn and its main rings from a distance. 

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4. Gale Crater on Mars

This look from our Curiosity Mars rover includes several geological layers in Gale crater to be examined by the mission, as well as the higher reaches of Mount Sharp beyond. The redder rocks of the foreground are part of the Murray formation. Pale gray rocks in the middle distance of the right half of the image are in the Clay Unit. A band between those terrains is "Vera Rubin Ridge," where the rover is working currently. The view combines six images taken with the rover's Mast Camera (Mastcam) on Jan. 24, 2017. 

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5. Sliver of Saturn

Cassini peers toward a sliver of Saturn's sunlit atmosphere while the icy rings stretch across the foreground as a dark band on March 31, 2017. This view looks toward the unilluminated side of the rings from about 7 degrees below the ring plane. 

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6. Dwarf Planet Ceres 

This image of the limb of dwarf planet Ceres shows a section of the northern hemisphere, as seen by our Dawn mission. Prominently featured is Occator Crater, home of Ceres' intriguing "bright spots." The latest research suggests that the bright material in this crater is comprised of salts left behind after a briny liquid emerged from below. 

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7. Martian Crater

This image from our Mars Reconnaissance Orbiter (MRO) shows a crater in the region with the most impressive known gully activity in Mars' northern hemisphere. Gullies are active in the winter due to carbon dioxide frost, but northern winters are shorter and warmer than southern winters, so there is less frost and less gully activity. 

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8. Dynamic Storm on Jupiter

A dynamic storm at the southern edge of Jupiter's northern polar region dominates this Jovian cloudscape, courtesy of Juno. This storm is a long-lived anticyclonic oval named North North Temperate Little Red Spot 1. Citizen scientists Gerald Eichstädt and Seán Doran processed this image using data from the JunoCam imager. 

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9. Rings Beyond Saturn’s Sunlit Horizon 

This false-color view from the Cassini spacecraft gazes toward the rings beyond Saturn's sunlit horizon. Along the limb (the planet's edge) at left can be seen a thin, detached haze. 

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10. Saturn’s Ocean-Bearing Moon Enceladus

Saturn's active, ocean-bearing moon Enceladus sinks behind the giant planet in a farewell portrait from Cassini. This view of Enceladus was taken by NASA's Cassini spacecraft on Sept. 13, 2017. It is among the last images Cassini sent back before its mission came to an end on Sept. 15, after nearly 20 years in space. 

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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).

Places to look for more of our pictures include solarsystem.nasa.gov/galleries, images.nasa.gov and www.jpl.nasa.gov/spaceimages.

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Solar System: Things to Know This Week

Our Dawn mission to the asteroid belt is no ordinary deep space expedition. 

Instead of traditional chemical rockets, the spacecraft uses sophisticated ion engines for propulsion. This enabled Dawn to become the first mission to orbit not one, but two different worlds — first the giant asteroid Vesta and now the dwarf planet Ceres. Vesta and Ceres formed early in the solar system's history, and by studying them, the mission is helping scientists go back in time to the dawn of the planets. To mark a decade since Dawn was launched on Sept. 27, 2007, here are 10 things to know about this trailblazing mission.

1. Ion Engines: Not Just for Sci-Fi Anymore

Most rocket engines use chemical reactions for propulsion, which tend to be powerful but short-lived. Dawn's futuristic, hyper-efficient ion propulsion system works by using electricity to accelerate ions (charged particles) from xenon fuel to a speed seven to 10 times that of chemical engines. Ion engines accelerate the spacecraft slowly, but they're very thrifty with fuel, using just milligrams of xenon per second (about 10 ounces over 24 hours) at maximum thrust. Without its ion engines, Dawn could not have carried enough fuel to go into orbit around two different solar system bodies. Try your hand at an interactive ion engine simulation.

2. Time Capsules 

Scientists have long wanted to study Vesta and Ceres up close. Vesta is a large, complex and intriguing asteroid. Ceres is the largest object in the entire asteroid belt, and was once considered a planet in its own right after it was discovered in 1801. Vesta and Ceres have significant differences, but both are thought to have formed very early in the history of the solar system, harboring clues about how planets are constructed. Learn more about Ceres and Vesta—including why we have pieces of Vesta here on Earth.

3. Portrait of a Dwarf Planet

This view of Ceres built from Dawn photos is centered on Occator Crater, home of the famous "bright spots." The image resolution is about 460 feet (140 meters) per pixel.

Take a closer look.

4. What's in a Name? 

Craters on Ceres are named for agricultural deities from all over the world, and other features carry the names of agricultural festivals. Ceres itself was named after the Roman goddess of corn and harvests (that's also where the word "cereal" comes from). The International Astronomical Union recently approved 25 new Ceres feature names tied to the theme of agricultural deities. Jumi, for example, is the Latvian god of fertility of the field. Study the full-size map.

5. Landslides or Ice Slides? 

Thanks to Dawn, evidence is mounting that Ceres hides a significant amount of water ice. A recent study adds to this picture, showing how ice may have shaped the variety of landslides seen on Ceres today.

6. The Lonely Mountain 

Ahuna Mons, a 3-mile-high (5-kilometer-high) mountain, puzzled Ceres explorers when they first found it. It rises all alone above the surrounding plains. Now scientists think it is likely a cryovolcano — one that erupts a liquid made of volatiles such as water, instead of rock. "This is the only known example of a cryovolcano that potentially formed from a salty mud mix, and that formed in the geologically recent past," one researcher said. Learn more.

7. Shining a Light on the Bright Spots 

The brightest area on Ceres, located in the mysterious Occator Crater, has the highest concentration of carbonate minerals ever seen outside Earth, according to studies from Dawn scientists. Occator is 57 miles (92 kilometers) wide, with a central pit about 6 miles (10 kilometers) wide. The dominant mineral of this bright area is sodium carbonate, a kind of salt found on Earth in hydrothermal environments. This material appears to have come from inside Ceres, and this upwelling suggests that temperatures inside Ceres are warmer than previously believed. Even more intriguingly, the results suggest that liquid water may have existed beneath the surface of Ceres in recent geological time. The salts could be remnants of an ocean, or localized bodies of water, that reached the surface and then froze millions of years ago. See more details.

8. Captain's Log 

Dawn's chief engineer and mission director, Marc Rayman, provides regular dispatches about Dawn's work in the asteroid belt. Catch the latest updates here.

9. Eyes on Dawn 

Another cool way to retrace Dawn's decade-long flight is to download NASA's free Eyes on the Solar System app, which uses real data to let you go to any point in the solar system, or ride along with any spacecraft, at any point in time—all in 3-D.

10. No Stamp Required

Send a postcard from one of these three sets of images that tell the story of dwarf planet Ceres, protoplanet Vesta, and the Dawn mission overall.

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It’s International Asteroid Day!

There are more than 700,000 known asteroids, but how much do you know about these rocky remnants left over from the birth of our solar system 4.6 billion years ago? 

Today, June 30 is International Asteroid Day. Here are some things to know about our fascinating space rubble.

1. A Place in Space 

Asteroids—named by British astronomer William Herschel from the Greek expression meaning "star-like"—are rocky, airless worlds that are too small to be called planets. But what they might lack in size they certainly make up for in number: An estimated 1.1 to 1.9 million asteroids larger than 1 kilometer are in the Main Belt between the orbits of Mars and Jupiter. And there are millions more that are smaller in size. Asteroids range in size from Vesta—the largest at about 329 miles (529 kilometers) wide—to bodies that are just a few feet across.

2. What Lies Beneath 

Asteroids are generally categorized into three types: carbon-rich, silicate, or metallic, or some combination of the three. Why the different types? It all comes down to how far from the sun they formed. Some experienced high temperatures and partly melted, with iron sinking to the center and volcanic lava forced to the surface. The asteroid Vesta is one example we know of today.

3. Small Overall 

If all of the asteroids were combined into a ball, they would still be much smaller than the Earth's moon.

4. Except for a Big One

In 1801, Giuseppe Piazzi discovered the first and then-largest asteroid, Ceres, orbiting between Mars and Jupiter. Ceres is so large that it encompasses about one-fourth of the estimated total mass of all the asteroids in the asteroid belt. In 2006, its classification changed from asteroid to  as a dwarf planet.

5. Mission to a Metal World 

NASA's Psyche mission will launch in 2022 to explore an all-metal asteroid—what could be the core of an early planet—for the very first time. And in October 2021, the Lucy mission will be the first to visit Jupiter's swarms of Trojan asteroids.

6. Near-Earth Asteroids

The term 'near' in near-Earth asteroid is actually a misnomer; most of these bodies do not come close to Earth at all. By definition, a near-Earth asteroid is an asteroid that comes within 28 million miles (44 million km) of Earth's orbit. As of June 19, 2017, there are 16,209 known near-Earth asteroids, with 1,803 classified as potentially hazardous asteroids (those that could someday pose a threat to Earth).

7. Comin' in Hot 

About once a year, a car-sized asteroid hits Earth's atmosphere, creates an impressive fireball, and burns up before reaching the surface.

8. But We're Keeping an Eye Out

Ground-based observatories and facilities such as Pan-STARRS, the Catalina Sky Survey, and ATLAS are constantly on the hunt to detect near-Earth asteroids. NASA also has a small infrared observatory in orbit about the Earth: NEOWISE. In addition to detecting asteroids and comets, NEOWISE also characterizes these small bodies.

9. Buddy System

Roughly one-sixth of the asteroid population have a small companion moon (some even have two moons). The first discovery of an asteroid-moon system was of asteroid Ida and its moon Dactyl in 1993.

10. Earthly Visitors 

Several NASA space missions have flown to and observed asteroids. The NEAR Shoemaker mission landed on asteroid Eros in 2001 and NASA's Dawn mission was the first mission to orbit an asteroid in 2011. In 2005, the Japanese spacecraft Hayabusa landed on asteroid Itokawa. Currently, NASA's OSIRIS-REx is en route to a near-Earth asteroid called Bennu; it will bring a small sample back to Earth for study.

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Solar System: Things to Know This Week

Has Cassini inspired you? Learn more about dwarf planet Ceres, get the latest images from the Keck Observatory and more!

1. Has Cassini Inspired You?

During nearly two decades in space, Cassini has been a source of inspiration to many. Has Cassini inspired you? Upload your artwork, photos, poems or songs to the social media platform of your choice, such as Instagram, YouTube, Facebook, Twitter or others. Tag it #CassiniInspires. Or, send it directly to: cassinimission@jpl.nasa.gov. We'll highlight some of the creations on this page. See examples and details at: saturn.jpl.nasa.gov/mission/cassiniinspires/

2. Dawn’s Shines a Light on Ceres

Our Dawn mission has found evidence for organic material on Ceres, a dwarf planet and the largest body in the main asteroid belt between Mars and Jupiter. Learn more: solarsystem.nasa.gov/news/2017/02/17/dawn-discovers-evidence-for-organic-material-on-ceres

3. Into the Vortex

A new device called the vortex coronagraph was recently installed inside NIRC2 (Near Infrared Camera 2) at the W.M. Keck Observatory in Hawaii and has delivered its first images, showing a ring of planet-forming dust around a star, and separately, a cool, star-like body, called a brown dwarf, lying near its companion star.

4. Enceladus: Cassini Cracks the Code of the Icy Moon

A puzzling sensor reading transformed our Cassini Saturn mission and created a new target in the search for habitable worlds beyond Earth, when on Feb. 17, 2005, Cassini made the first-ever close pass over Saturn’s moon. Since our two Voyager spacecraft made their distant flybys of Enceladus about 20 years prior, scientists had anticipated the little moon would be an interesting place to visit. Enceladus is bright white -- the most reflective object in the solar system, in fact -- and it orbits in the middle of a faint ring of dust-sized ice particles known as Saturn’s E ring. Scientists speculated ice dust was being kicked off its surface somehow. But they presumed it would be, essentially, a dead, airless ball of ice.

What Cassini saw didn't look like a frozen, airless body. Instead, it looked something like a comet that was actively emitting gas. The magnetometer detected that Saturn’s magnetic field, which envelops Enceladus, was perturbed above the moon's south pole in a way that didn't make sense for an inactive world. Could it be that the moon was actively replenishing gases it was breathing into space? Watch the video.

5. Descent Into a Frozen Underworld

Our planet's southernmost active volcano reaches 12,448 feet (3,794 meters) above Ross Island in Antarctica. It's a good stand-in for a frozen alien world, the kind we want to send robots to someday. Learn more: solarsystem.nasa.gov/news/2017/02/13/descent-into-a-frozen-underworld

Discover the full list of 10 things to know about our solar system this week HERE.

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Solar System: Things to Know This Week

Our solar system is huge, let us break it down for you. Here are a few things to know this week:

1. Up at Jupiter, It’s Down to Business

Ever since our Juno mission entered Jupiter's orbit on July 4, engineers and scientists have been busy getting their newly arrived spacecraft ready for operations. Juno's science instruments had been turned off in the days leading up to Jupiter orbit insertion. As planned, the spacecraft powered up five instruments on July 6, and the remaining instruments should follow before the end of the month. The Juno team has also scheduled a short trajectory correction maneuver on July 13 to refine the orbit.

2. The Shadows Know

Scientists with our Dawn mission have identified permanently shadowed regions on the dwarf planet Ceres. Most of these areas likely have been cold enough to trap water ice for a billion years, suggesting that ice deposits could exist there now (as they do on the planet Mercury). Dawn is looking into it.

3. Frosts of Summer

Some dusty parts of Mars get as cold at night year-round as the planet's poles do in winter, even in regions near the equator in summer, according to new findings based on Mars Reconnaissance Orbiter observations. The culprit may be Mars' ever-present dust.

4. Can You Hear Me Now?

The OSIRIS-REx spacecraft is designed to sample an asteroid and return that sample to Earth. After launch in Sept., the mission's success will depend greatly on its communications systems with Earth to relay everything from its health and status to scientific findings from the asteroid Bennu. That's why engineers from our Deep Space Network recently spent a couple of weeks performing detailed tests of the various communications systems aboard OSIRIS-REx.

5. Cometary Close-ups

The Rosetta spacecraft has taken thousands of photographs of Comet 67/P. The European Space Agency (ESA) is now regularly releasing the highest-resolution images. The word "stunning" is used a lot when referring to pictures from space—and these ones truly are. See the latest HERE.

Want to learn more? Read our full list of the 10 things to know this week about the solar system HERE.

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Solar System: Things to Know This Week

Our solar system is huge, let us break it down for you. Here are a few things to know this week:

1. The View from the Far Shore

The rugged shores of Pluto’s highlands come into sharp view in a newly released image from our New Horizons spacecraft. This latest view zooms in on the southeastern portion of Pluto’s great ice plains, where they border dark highlands formerly named Krun Macula.

2. Dawn’s Latest Light

Our Dawn mission has now completed more than 1,000 orbital revolutions since entering into Ceres’ gravitational grip in March 2015. The probe is healthy and performing its ambitious assignments impeccably. See what it has revealed lately HERE.

3. Counting Down

Our OSIRIS-REx mission to the asteroid Bennu is now entering the final preparations for its planned launch in September. In a new interview, the mission’s principal investigator reports on the final pre-flight tests happening at our Kennedy Space Center in Florida.

4. Deep Dive

Three successful engine maneuvers to bring the lowest part of the spacecraft’s orbit down to just 74 miles (119 km) above the surface of Mars, the MAVEN mission’s fifth deep dip campaign has begun. MAVEN is studying the planet’s atmosphere up close.

5. Storm Season

Meanwhile, other robotic Mars orbiters have revealed that a pattern of three large regional dust storms occurs with similar timing most Martian years. The seasonal pattern was detected from dust storms’ effects on atmospheric temperatures, which spacecraft have been monitoring since 1997.

Want to learn more? Read our full list of the 10 things to know this week about the solar system HERE.

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Solar System: Things to Know This Week

In addition to the Mercury transit of the sun today, there are a few other things you should know about our solar system this week:

1. Mars, Ready for its Close-Up

Mars will soon be closer to Earth than it has been for 11 years, presenting a great opportunity for backyard sky watchers.

2. Fire and Ice

Our spacecraft have an even closer view of Mars, and that fact regularly leads to some intriguing discoveries. The latest: volcanoes may have erupted beneath an ice sheet there billions of years ago. The above image is a mineral map of part of the Martian surface.

3. Icy Hydra

Meanwhile, our New Horizons spacecraft has sent home the first compositional data about Pluto's four small moons. The new data show the surface of Hydra is dominated by nearly pristine water ice--confirming hints that scientists picked up in images showing Hydra's highly reflective surface.

4. Ceres, Ever Sharper

The mission director for our Dawn mission writes, "Ceres, which only last year was hardly more than a fuzzy blob against the stars, is now a richly detailed world, and our portrait grows more elaborate every day."

5. Join us at Jupiter

Our Juno mission arrives at the giant planet on Jul. 4. Meanwhile, all amateur astronomers are invited to take part in a worldwide effort to identify potential observations for the spacecraft to make once it's in orbit. Find out how to join HERE.

Want to learn more? Read our full list of the 10 things to know this week about the solar system HERE.

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Solar System: Things to Know This Week

Here are a few things you should know about our solar system this week:

1. The Bright and the Beautiful

In its lowest-altitude mapping orbit, at a distance of 240 miles (385 kilometers) from Ceres, Dawn has provided scientists with spectacular views of the dwarf planet, especially of its bright, young, hexagonal craters like Haulani.

2. Mars Needs Brains

NASA is soliciting ideas from U.S. industry for designs of a Mars orbiter for potential launch in the 2020s. The satellite would provide advanced communications and imaging, as well as robotic science exploration, in support of NASA's Journey to Mars. This effort seeks to take advantage of industry capabilities to improve deep space, solar electric propulsion-enabled orbiters.

3. Seeing Double

NASA measured a solar flare from two different spots in space, using three solar observatories. During a December 2013 solar flare, three sun-observing spacecraft captured the most comprehensive observations ever of an electromagnetic phenomenon called a current sheet.

4. Set a Course for Europa

This artist's rendering shows NASA's Europa mission spacecraft, which is being developed for a launch in the 2020s. The mission would place a spacecraft in orbit around Jupiter in order to perform a detailed investigation of the giant planet's moon Europa—a world that shows strong evidence for an ocean of liquid water beneath its icy crust and which could host conditions favorable for life.

5. Go Deep

Jupiter is huge, powerful and spectacular. But what lies hidden inside the giant planet? The Juno mission arrives at Jupiter in July to help us find out. Join Dr. Fran Bagenal to learn more about the mission and how it plans to delve deep into Jupiter's secrets this year.

Want to learn more? Read our full list of things to know this week about the solar system HERE.

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Solar System: Things to Know This Week

Our solar system is huge, so let us break it down for you. Here are five things you need to know this week:

1. The Lure of the Rings

Scientists and stargazers alike can’t resist the call of Saturn’s rings, or of its moon Titan. Both have been under close scrutiny by the Cassini spacecraft lately, and there are striking new pictures to prove it. Check out the latest images HERE.

2. A New Moon Rises

The Lunar Reconnaissance Orbiter has captured dramatic landscapes on the moon for more than six years. “A New Moon Rises,” now on display at the Smithsonian National Air and Space Museum in Washington, DC, showcases those images ranging from Apollo landing sites to mountains that rise out of the darkness of the lunar poles. See an online version of the exhibit HERE.  

3. Around the (Giant) World in (Just Under) 88 Days

The Juno mission is closing in on Jupiter. On July 4, the spacecraft enters orbit around the king of planets. Learn more about Juno HERE.

4. Spiders and Volcanoes and Glaciers, Oh My

The more data that New Horizons spacecraft sends down about Pluto and its moons, the more there is to fascinate explorers, from spider-shaped canyons to signs of glacial flow. Take a peek at the new finds on Pluto HERE.

5. World of Wonders

Hexagonal craters, mysterious mountains, eye-catching bright patches — the dwarf planet Ceres is proving to be an intriguing place. The Dawn mission is looking for clues to how it works. See the latest from Ceres HERE.

Want to learn more? Read our full list of the 10 things to know this week about the solar system HERE.

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Travel Posters of Fantastic Excursions

What would the future look like if people were regularly visiting to other planets and moons? These travel posters give a glimpse into that imaginative future. Take a look and choose your destination:

The Grand Tour

Our Voyager mission took advantage of a once-every-175-year alignment of the outer planets for a grand tour of the solar system. The twin spacecraft revealed details about Jupiter, Saturn, Uranus and Neptune – using each planet’s gravity to send them on to the next destination.

Mars

Our Mars Exploration Program seeks to understand whether Mars was, is, or can be a habitable world. This poster imagines a future day when we have achieved our vision of human exploration of the Red Planet and takes a nostalgic look back at the great imagined milestones of Mars exploration that will someday be celebrated as “historic sites.”

Earth

There’s no place like home. Warm, wet and with an atmosphere that’s just right, Earth is the only place we know of with life – and lots of it. Our Earth science missions monitor our home planet and how it’s changing so it can continue to provide a safe haven as we reach deeper into the cosmos.

Venus

The rare science opportunity of planetary transits has long inspired bold voyages to exotic vantage points – journeys such as James Cook’s trek to the South Pacific to watch Venus and Mercury cross the face of the sun in 1769. Spacecraft now allow us the luxury to study these cosmic crossings at times of our choosing from unique locales across our solar system.

Ceres

Ceres is the closest dwarf planet to the sun. It is the largest object in the main asteroid belt between Mars and Jupiter, with an equatorial diameter of about 965 kilometers. After being studied with telescopes for more than two centuries, Ceres became the first dwarf planet to be explored by a spacecraft, when our Dawn probe arrived in orbit in March 2015. Dawn’s ongoing detailed observations are revealing intriguing insights into the nature of this mysterious world of ice and rock.

Jupiter

The Jovian cloudscape boasts the most spectacular light show in the solar system, with northern and southern lights to dazzle even the most jaded space traveler. Jupiter’s auroras are hundreds of times more powerful than Earth’s, and they form a glowing ring around each pole that’s bigger than our home planet. 

Enceladus

The discovery of Enceladus’ icy jets and their role in creating Saturn’s E-ring is one of the top findings of the Cassini mission to Saturn. Further Cassini discoveries revealed strong evidence of a global ocean and the first signs of potential hydrothermal activity beyond Earth – making this tiny Saturnian moon one of the leading locations in the search for possible life beyond Earth.

Titan

Frigid and alien, yet similar to our own planet billions of years ago, Saturn’s largest moon, Titan has a thick atmosphere, organic-rich chemistry and surface shaped by rivers and lakes of liquid ethane and methane. Our Cassini orbiter was designed to peer through Titan’s perpetual haze and unravel the mysteries of this planet-like moon.

Europa

Astonishing geology and the potential to host the conditions for simple life making Jupiter’s moon Europa a fascinating destination for future exploration. Beneath its icy surface, Europa is believed to conceal a global ocean of salty liquid water twice the volume of Earth’s oceans. Tugging and flexing from Jupiter’s gravity generates enough heat to keep the ocean from freezing.

You can download free poster size images of these thumbnails here: http://www.jpl.nasa.gov/visions-of-the-future/

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What Are the Bright Spots on Ceres?

Dwarf planet Ceres has more than 130 bright areas, and most of them are associated with impact craters. Now, Ceres has revealed some of its well-kept secrets in two new studies in the journal Nature, thanks to data from our Dawn spacecraft.

Two studies have been looking into the mystery behind these bright areas. One study identifies this bright material as a kind of salt, while the other study suggests the detection of ammonia-rich clays. 

Study authors write that the bright material is consistent with a type of magnesium sulfate called hexahydrite. A different type of magnesium sulfate is familiar on Earth as Epsom salt.

Researchers, using images from Dawn’s framing camera, suggest that these salt-rich areas were left behind when water-ice sublimated in the past. Impacts from asteroids would have unearthed the mixture of ice and salt.

An image of Occator Crater (below) shows the brightest material on Ceres. Occator itself is 60 miles in diameter, and its central pit, covered by this bright material, measures about 6 miles wide. With its sharp rim and walls, it appears to be among the youngest features on the dwarf planet.

In the second nature study, members of the Dawn science team examined the composition of Ceres and found evidence for ammonia-rich clays. Why is this important?

Well, ammonia ice by itself would evaporate on Ceres today, because it is too warm. However, ammonia molecules could be stable if present in combination with other minerals. This raises the possibility that Ceres did not originate in the main asteroid belt between Mars and Jupiter, where it currently resides. But instead, might have formed in the outer solar system! Another idea is that Ceres formed close to its present position, incorporating materials that drifted in from the outer solar system, near the orbit of Neptune, where nitrogen ices are thermally stable.

As of this week, our Dawn spacecraft has reached its final orbital altitude at Ceres (about 240 miles from the surface). In mid-December, it will begin taking observations from this orbit, so be sure to check back for details!

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Solar System: 5 Things To Know This Week

Our solar system is huge, so let us break it down for you. Here are 5 things to know this week: 

1. Make a Wish

The annual Leonids meteor shower is not known for a high number of "shooting stars" (expect as many as 15 an hour), but they're usually bright and colorful. They're fast, too: Leonids travel at speeds of 71 km (44 miles) per second, which makes them some of the fastest. This year the Leonids shower will peak around midnight on Nov. 17-18. The crescent moon will set before midnight, leaving dark skies for watching. Get more viewing tips HERE.

2. Back to the Beginning

Our Dawn mission to the dwarf planet Ceres is really a journey to the beginning of the solar system, since Ceres acts as a kind of time capsule from the formation of the asteroid belt. If you'll be in the Washington DC area on Nov. 19, you can catch a presentation by Lucy McFadden, a co-investigator on the Dawn mission, who will discuss what we've discovered so far at this tiny but captivating world. Find out how to attend HERE. 

3. Keep Your Eye on This Spot

The Juno spacecraft is on target for a July 2016 arrival at the giant planet Jupiter. But right now, your help is needed. Members of the Juno team are calling all amateur astronomers to upload their telescopic images and data of Jupiter. This will help the team plan their observations. Join in HERE.

4. The Ice Volcanoes of Pluto

The more data from July's Pluto flyby that comes down from the New Horizons spacecraft, the more interesting Pluto becomes. The latest finding? Possible ice volcanoes. Using images of Pluto's surface to make 3-D topographic maps, scientists discovered that some mountains on Pluto, such as the informally named Piccard Mons and Wright Mons, had structures that suggested they could be cryovolcanoes that may have been active in the recent geological past.

5. Hidden Storm

Cameras aboard the Cassini spacecraft have been tracking an impressive cloud hovering over the south pole of Saturn's moon Titan. But that cloud has turned out to be just the tip of the iceberg. A much more massive ice cloud system has been found lower in the stratosphere, peaking at an altitude of about 124 miles (200 kilometers).

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Solar System: Top 5 Things to Know This Week

1. A Ceres of Fortunate Events

Our Dawn mission continues its exploration at Ceres, and the team is working with the data coming back to Earth, looking for explanations for the tiny world’s strange features. Follow Dawn’s expedition HERE.

2. Icy Moon Rendezvous

One of the most interesting places in the entire solar system is Saturn’s moon Enceladus, with its underground ocean and spectacular geyser plume. This month, the Cassini spacecraft will be buzzing close by Enceladus several times, the last such encounters of the mission. On October 14, Cassini will perform a targeted flyby at a distance of just 1,142 miles (1,838 kilometers) over the moon’s northern latitudes. Ride along with Cassini HERE.

3. Make Your Own Mars Walkabout

You can retrace Opportunity’s journey, see where the Curiosity rover is now, or even follow along with fictional astronaut Mark Watney from The Martian movie using the free online app MarsTrek. The app lets you zoom in on almost any part of the planet and see images obtained by our spacecraft, so you can plan your on Red Planet excursion. Take a hike HERE.

4. Elusive Features on Jupiter

New imagery from our Hubble Space Telescope is capturing details never before seen on Jupiter. High-resolution maps and spinning globes, rendered in the 4K Ultra HD format, reveal an elusive wave and changes to Jupiter’s Great Red Spot. Explore Jupiter HERE.

5. Mr. Blue Sky

Another week, another amazing picture from Pluto. The first color images of Pluto’s atmospheric hazes, returned by our New Horizons spacecraft last week, reveal that the hazes are blue. Who would have expected a blue sky in the Kuiper Belt? Most of the data collected during July’s Pluto flyby remains aboard the spacecraft, but the team publishes new batches of pictures and other findings on a weekly basis. Keep up with the latest HERE.

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