DYK - Blog Posts

Weird Magnetic Behavior in Space

In between the planets, stars and other bits of rock and dust, space seems pretty much empty. But the super-spread out matter that is there follows a different set of rules than what we know here on Earth.

For the most part, what we think of as empty space is filled with plasma. Plasma is ionized gas, where electrons have split off from positive ions, creating a sea of charged particles. In most of space, this plasma is so thin and spread out that space is still about a thousand times emptier than the vacuums we can create on Earth. Even still, plasma is often the only thing out there in vast swaths of space — and its unique characteristics mean that it interacts with electric and magnetic fields in complicated ways that we are just beginning to understand.

Five years ago, we launched a quartet of satellites to study one of the most important yet most elusive behaviors of that material in space — a kind of magnetic explosion that had never before been adequately studied up close, called magnetic reconnection. Here are five of the ways the Magnetospheric Multiscale mission (MMS) has helped us study this intriguing magnetic phenomenon.

1. Seeing magnetic explosions up close

Magnetic reconnection is the explosive snapping and forging of magnetic fields, a process that can only happen in plasmas — and it's at the heart of space weather storms that manifest around Earth.

When the Sun launches clouds of solar material — which is also made of plasma — toward Earth, the magnetic field embedded within the material collides with Earth's huge global magnetic field. This sets off magnetic reconnection that injects energy into near-Earth space, triggering a host of effects — induced electric currents that can harm power grids, to changes in the upper atmosphere that can affect satellites, to rains of particles into the atmosphere that can cause the glow of the aurora.  

Though scientists had theorized about magnetic reconnection for decades, we'd never had a chance to study it on the small scales at which it occurs. Determining how magnetic reconnection works was one of the key jobs MMS was tasked with — and the mission quickly delivered. Using instruments that measured 100 times faster than previous missions, the MMS observations quickly determined which of several 50-year-old theories about magnetic reconnection were correct. It also showed how the physics of electrons dominates the process — a subject of debate before the launch.

2. Finding explosions in surprising new places

In the five years after launch, MMS made over a thousand trips around Earth, passing through countless magnetic reconnection events. It saw magnetic reconnection where scientists first expected it: at the nose of Earth's magnetic field, and far behind Earth, away from the Sun. But it also found this process in some unexpected places — including a region thought to be too tumultuous for magnetic reconnection to happen.

As solar material speeds away from the Sun in a flow called the solar wind, it piles up as it encounters Earth's magnetic field, creating a turbulent region called the magnetosheath. Scientists had only seen magnetic reconnection happening in relatively calm regions of space, and they weren't sure if this process could even happen in such a chaotic place. But MMS' precise measurements revealed that magnetic reconnection happens even in the magnetosheath.  

MMS also spotted magnetic reconnection happening in giant magnetic tubes, leftover from earlier magnetic explosions, and in plasma vortices shaped like ocean waves — based on the mission's observations, it seems magnetic reconnection is virtually ubiquitous in any place where opposing magnetic fields in a plasma meet.  

3. How energy is transferred

Magnetic reconnection is one of the major ways that energy is transferred in plasma throughout the universe — and the MMS mission discovered that tiny electrons hold the key to this process.

Electrons in a strong magnetic field usually exhibit a simple behavior: They spin tight spirals along the magnetic field. In a weaker field region, where the direction of the magnetic field reverses, the electrons go freestyle — bouncing and wagging back and forth in a type of movement called Speiser motion.

Flying just 4.5 miles apart, the MMS spacecraft measured what happens in a magnetic field with intermediate strength: These electrons dance a hybrid, meandering motion — spiraling and bouncing about before being ejected from the region. This takes away some of the magnetic field’s energy.

4. Surpassing computer simulations

Before we had direct measurements from the MMS mission, computer simulations were the best tool scientists had to study plasma's unusual magnetic behavior in space. But MMS' data has revealed that these processes are even more surprising than we thought — showing us new electron-scale physics that computer simulations are still trying to catch up with. Having such detailed data has spurred theoretical physicists to rethink their models and understand the specific mechanisms behind magnetic reconnection in unexpected ways. 

5. In deep space & nuclear reactions

Although MMS studies plasma near Earth, what we learn helps us understand plasma everywhere. In space, magnetic reconnection happens in explosions on the Sun, in supernovas, and near black holes.

These magnetic explosions also happen on Earth, but only under the most extreme circumstances: for example, in nuclear fusion experiments. MMS' measurements of plasma's behavior are helping scientists better understand and potentially control magnetic reconnection, which may lead to improved nuclear fusion techniques to generate energy more efficiently.

This quartet of spacecraft was originally designed for a two-year mission, and they still have plenty of fuel left — meaning we have the chance to keep uncovering new facets of plasma's intriguing behavior for years to come. Keep up with the latest on the mission at nasa.gov/mms.

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10 Ways the 2010s Pushed Communication and Navigation into the Future!

We transmit vast amounts of data from space, letting all of our satellites “phone home.” Imagery from far off regions of our solar system, beautiful visions of other galaxies and insights into planet Earth flow through our communications networks. 

Our Space Communications and Navigation (SCaN) program is dedicated to making sure we precisely track, command and control our spacecraft. All the while, they develop bold new technologies and capabilities for Artemis – our sustainable lunar exploration program that will place the first woman and the next man on the Moon in 2024. 

As we prepare to say goodbye to the 2010s, let’s take a look at 10 of the biggest milestones in space communications and navigation of the past decade. 

1. Continuous global communications? TDRS has you covered.

From 2013 to 2017, we launched three Tracking and Data Relay Satellites, or TDRS for short. These new satellites replenished a fleet that has been around since the early 1980s, allowing us to provide continuous global communications coverage into the next decade. Missions like the International Space Station depend on TDRS for 24/7 coverage, allowing our astronauts to call home day or night.

2. Binge watching on the Moon? Laser communications will make it possible.

Imagine living at the Moon. With the Artemis program, we’re making it happen! However, we can’t live there without decent internet, right? In 2013, we conducted the Lunar Laser Communication Demonstration (LLCD). This was the first high-speed laser communications demonstration from the Moon, transmitting data at a whopping 622 megabits per second, which is comparable to many high-speed fiber-optic connections enjoyed at home on Earth! Our LLCD sent back high-definition video with no buffering. 

3. Record Breaking GPS navigation, at your service.

Space communications is just one piece of the SCaN puzzle. We do navigation too! We even break records for it. In 2016, our Magnetospheric Multiscale (MMS) mission broke the world record for highest altitude GPS fix at 43,500 miles above Earth. In 2017, they broke it again at 93,200 miles. Earlier this year, they broke it a third time at 116,200 miles from Earth — about halfway to the Moon!

Thanks to MMS, our navigation engineers believe that GPS and similar navigation constellations could play a significant role in the navigation architecture of our planned Gateway spaceship in lunar orbit!

4. Crashing planes as part of the game – of research!  

Then there was that one summer we crashed three planes in the name of research! In 2015, our Search and Rescue office tested crash scenarios at Langley Research Center’s Landing and Impact Research Facility to improve the reliability of emergency beacons installed in planes. After the study, we made recommendations on how pilots should install these life-saving beacons, increasing their chances of survival in the event of a crash. The Federal Aviation Administration adopted these recommendations this year!

5. The Deep Space Atomic Clock takes flight. 

Missions venturing into deep space want the autonomy to make decisions without waiting for a commands from Earth. That’s why we launched the Deep Space Atomic Clock this past year. This itty-bitty technology demonstration is a small, ultra-stable timekeeping device that could enable autonomous navigation!

6. 50 never looked so good – for our Deep Space Network. 

In 2013, our Deep Space Network celebrated its 50th birthday! This is the network that transmitted Neil Armstrong’s famous words, "That's one small step for (a) man, one giant leap for mankind." Some of its more recent accomplishments? Gathering the last bits of data before Cassini dove into Saturn’s upper atmosphere, pulling down the “heart” of Pluto and talking to the Voyager probes as they journeyed into interstellar space!

7. SCaN Testbed becomes an official Hall of Famer. 

In 2012, we installed the SCaN Testbed, which looks like a blue box in the above picture, on the space station! We built the testbed out of Software Defined Radios, which can change their functionality and employ artificial intelligence. These radios will help us adapt to the increasingly crowded communications landscape and improve the efficiency of radio technology. The Testbed was so ground-breaking that it was inducted into the Space Technology Hall of Fame in 2019.

8. Moon mission communications system, secured! 

Just a few weeks ago, we held a ribbon-cutting for the Near Earth Network’s Launch Communications Segment, which will support Artemis missions as they rocket toward the Moon! During initial, dynamic phases of launch, the segment’s three stations will provide communications between astronauts and mission controllers, giving them the data necessary to ensure crew safety. 

9. Deep Space Station antenna introduces “beam waveguide” technology. 

On October 1, 2014, in Canberra, Australia, the Deep Space Network’s Deep Space Station 35 (DSS-35) antenna went operational. It was the first of a number of new antennas built to support the growing number of deep space missions! The antenna is different from other antennas that were built before it. Older antennas had a lot of their equipment stored high up on the antenna above the dish. DSS-35 uses “beam waveguide” technology that stores that equipment underground. This makes the weight sitting on the dish much lighter, cuts down on interference and makes the antenna much easier to operate and maintain.

10. Hello, Alaska! 

Last — but certainly not least — we expanded our presence in the 49th state, Alaska! While this picture might look like antennas rising from the forests of  Endor, the one in the foreground is actually an antenna we installed in 2014 in partnership with the University of Alaska Fairbanks. Because of its proximity to the polar north, this 11-meter beauty is uniquely situated to pull down valuable Earth science data from our polar-orbiting spacecraft, contributing to scientists’ understanding of our changing planet!

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Protecting our Home Planet 🌎

Did you ever wonder how we spots asteroids that may be getting too close to Earth for comfort? Wonder no more. Our Planetary Defense Coordination Office does just that. Thanks to a variety of ground and space based telescopes, we’re able to detect potentially hazardous objects so we can prepare for the unlikely threat against our planet. 

What is a near-Earth object?

Near-Earth objects (NEOs) are asteroids and comets that orbit the Sun, but their orbits bring them into Earth’s neighborhood – within 30 million miles of Earth’s orbit.

These objects are relatively unchanged remnant debris from the solar system’s formation some 4.6 billion years ago. Most of the rocky asteroids originally formed in the warmer inner solar system between the orbits of Mars and Jupiter, while comets, composed mostly of water ice with embedded dust particles, formed in the cold outer solar system.

Who searches for near-Earth objects?

Our Near-Earth Object (NEO) Observations Program finds, tracks and monitors near-Earth asteroids and comets. Astronomers supported by the program use telescopes to follow up the discoveries to make additional measurements, as do many observatories all over the world. The Center for Near-Earth Object Studies, based at our Jet Propulsion Laboratory, also uses these data to calculate high-precision orbits for all known near-Earth objects and predict future close approaches by them to Earth, as well as the potential for any future impacts.

How do we calculate the orbit of a near-Earth object?

Scientists determine the orbit of an asteroid by comparing measurements of its position as it moves across the sky to the predictions of a computer model of its orbit around the Sun. The more observations that are used and the longer the period over which those observations are made, the more accurate the calculated orbit and the predictions that can be made from it.

How many near-Earth objects have been discovered so far?

At the start of 2019, the number of discovered NEOs totaled more than 19,000, and it has since surpassed 20,000. An average of 30 new discoveries are added each week. More than 95 percent of these objects were discovered by NASA-funded surveys since 1998, when we initially established its NEO Observations Program and began tracking and cataloguing them.

Currently the risk of an asteroid striking Earth is exceedingly low, but we are constantly monitoring our cosmic neighborhood. Have more questions? Visit our Planetary Defense page to explore how we keep track of near-Earth objects. 

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DYK the bright clusters and nebulae of planet Earth's night sky are often named for flowers or insects? 

Though its wingspan covers over 3 light-years, NGC 6302: The Butterfly Nebula is no exception! With an estimated surface temperature of about 250,000 degrees C, the dying central star of this particular planetary nebula has become exceptionally hot, shining brightly in ultraviolet light but hidden from direct view by a dense torus of dust. This sharp close-up was recorded by the Hubble Space Telescope in 2009. The Hubble image data is reprocessed here, showing off the remarkable details of the complex planetary nebula.

Image Credit: NASA, ESA, Hubble, HLA; Reprocessing & Copyright: Robert Eder

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