For the first time, scientists used the joint power of NASA’s Hubble and James Webb Space Telescopes to study some of the most far-flung bodies in our solar system, Trans-Neptunian Objects (TNOs). Some of these are the smallest and faintest ever directly seen. The researchers unexpectedly found fewer small TNOs than they expected, and that the colors of these bodies followed the same relationships as their larger family members.

These objects are typically small, faint, icy bodies orbiting the Sun beyond the orbit of Neptune. Most are more than 100 million times dimmer than objects visible to the unaided eye. In two complementary papers published Tuesday in The Astronomical Journal, teams analyzed the color, composition, and size distribution of 27 newly discovered tiny, dim TNOs. 

This class of small bodies offers the best view into an early stage of planet-building, when a disk of dust and pebbles in orbit around the Sun coalesced into city-sized “planetesimals” — the solid building blocks that clump together to form planets — but had not yet merged into full-sized worlds.  Beyond Neptune, this second stage never happened, leaving behind a frozen population of planetesimals.

In the deepest TNO survey to date, teams led by PhD candidates from the University of Victoria in Canada, under the guidance of the National Research Council of Canada, and Northern Arizona University in Flagstaff examined a patch of sky simultaneously with Hubble, observing the TNOs’ visible light, and Webb, observing their infrared light. The team of researchers measured the objects’ colors, which are like a fingerprint of the surface composition, as well as their sizes and determined their orbits. 

In the coordinated observations, the teams studied two different types of TNOs. The first, dynamically “cold” TNOs, are on their original, relatively circular orbits around the Sun in the plane of the solar system. The second type, dynamically “hot” TNOs, formed between the current locations of Uranus and Neptune but were pushed outward where they are today when the outer gas giants migrated early in the solar system’s history. Today they reside in highly elliptical orbits and move in and out of the plane of our solar system.

Prior to these observations, astronomers thought that small TNOs from both hot and cold populations would have undergone many collisions, changing their surfaces compared to larger TNOs. But that’s not what the observations showed. Instead, the small bodies look like their larger counterparts. This implies that collisions are not changing the surfaces significantly—perhaps because there are fewer collisions than expected, or because the TNOs somehow retain their primordial, pre-collision compositions. The teams are still trying to unravel this mystery.

“You could imagine a scenario where getting knocked around and fragmented would change the surface composition, and then you would see a different surface color for tiny TNOs compared to their larger siblings. So it’s really fascinating to see that the smallest objects are somehow ‘remembering’ and preserving the history of how they were made,” said Northern Arizona University PhD candidate Anastasia Morgan, who led the study of color and composition. 

“These dynamically ‘hot’ TNOs retain a signature of where they were born, even though they’ve been orbitally scrambled since then,” said co-author David Trilling of Northern Arizona University.

Both the “hot” and “cold” populations seem to keep the same colors as when they were formed, with little change since the birth of the solar system. 

The Webb data also allowed researchers to measure the number of objects of each size. They found that the overall size distributions for both populations were surprisingly similar.

“It’s very interesting that the process of planetesimal formation ends up producing the same distribution of sizes for both cold and hot populations, despite forming in different regions of the early solar system. The process seems to be insensitive to disk conditions, producing similar planetesimal sizes whether the disk is hot or cold, and dense or fluffy,” said University of Victoria PhD candidate Marielle Eduardo, who led the study on size distribution. 

Researchers also found fewer of these very small bodies than they expected based on some planet formation models. Webb discovered 27 new, remarkably dim TNOs, one so faint it is equivalent to standing on Earth and seeing a small swarm of fireflies on the Moon. The smallest one they observed has a diameter of about 3 miles (5 kilometers), which is about five times smaller than what is possible to detect with the most sensitive ground-based telescopes.

This project would not have been possible without Hubble and Webb working together to detect and characterize these TNOs. With Hubble’s sensitivity in visible light and Webb’s in infrared, the space telescopes provide more insights than either can on its own.

The Hubble Space Telescope has been operating for over three decades and continues to make ground-breaking discoveries that shape our fundamental understanding of the universe. Hubble is a project of international cooperation between NASA and ESA (European Space Agency). NASA’s Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope and mission operations. Lockheed Martin Space, based in Denver, also supports mission operations at Goddard. The Space Telescope Science Institute in Baltimore, which is operated by the Association of Universities for Research in Astronomy, conducts Hubble science operations for NASA.

The James Webb Space Telescope is the world’s premier space science observatory. Webb is solving mysteries in our solar system, looking beyond to distant worlds around other stars, and probing the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and CSA (Canadian Space Agency).

To learn more about NASA’s space telescopes, visit:
https://science.nasa.gov/universe

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The BepiColombo mission cleared a major milestone this week in the final stretch of an eight-year interplanetary voyage to Mercury, the hard-to-reach, scorching hot iron world at the Solar System's innermost frontier.

The robotic science mission, with a price tag of nearly $2 billion, is led by the European Space Agency with contributions from Japan and the United States. Since its launch in 2018, BepiColombo has spiraled closer to the Sun using a combination of plasma propulsion and a series of flybys of Earth, Venus, and Mercury. The maneuvers changed the spacecraft's velocity and steered it toward a final encounter with Mercury later this year.

Next time it reaches Mercury, BepiColombo will be traveling at just the right speed for the planet's gravity to capture the spacecraft into orbit. Scientists working on interplanetary missions are accustomed to long waits for scientific payoffs. It took nearly 10 years for NASA's New Horizons spacecraft to travel from Earth to Pluto. It turns out traveling to fleet-footed Mercury and then entering orbit requires more energy, or delta-v, than sending a probe to fly by Pluto.

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Recent observations with NASA’s Hubble Space Telescope have revealed a giant, evolving, 10-sided atmospheric wave encircling Saturn’s south pole. This discovery marks the first time a large, regular-sided jet pattern has been observed in the planet’s southern hemisphere. The feature appears remarkably similar to Saturn’s famous hexagon at its northern pole, but is also distinctly different, suggesting scientists may be witnessing a new atmospheric phenomenon develop on the iconic gas giant.

The results published Wednesday in the journal Science Advances. 

By piecing together several years of Hubble observations dating back to 2023, researchers found subtle hints of the structure beginning to emerge before it became a clearly defined pattern. Those observations were taken as part of Hubble’s Outer Planet Atmospheres Legacy (OPAL) program, which has photographed the outer planets annually for more than a decade. 

“We’ve never seen anything quite like this in Saturn’s southern hemisphere,” said Amy Simon, study co-author and OPAL principal investigator, NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “The northern hexagon has been there every time we’ve looked for more than 40 years. This feature is different — it appears to be strengthening, giving us the rare opportunity to watch a giant atmospheric pattern develop.”

The discovery was possible because Saturn’s changing seasons gradually brought the planet’s south pole back into view from Earth, where astronomers who collectively analyze images of Saturn from ground-based observatories first identified it.

Agustín Sánchez-Lavega, lead author of the new study, is a researcher at the University of the Basque Country in Spain. The university manages a website, called Planetary Virtual Observatory Laboratory, that accepts ground-based images of solar system planets contributed by observers all over the world. It was in those images, first in 2024, that Sánchez-Lavega and amateur astronomers Trevor Barry and Jean-Paul Oger noticed a subtle undulating band along the southern pole. Additional 2025 imagery taken from the ground hinted even more strongly toward this decagon structure.

That’s when the Hubble observations come into the picture. Hubble’s view from space offers unmatched image sharpness and spatial resolution over full rotations of Saturn, without smearing by Earth’s atmosphere. 

“Given Saturn’s symmetry in its north-south jet stream system, we have been searching for a counterpart to Saturn’s northern hexagon on the south pole in Hubble images since 1990,” Sánchez-Lavega said. “Images from NASA’s Cassini spacecraft, which orbited Saturn between 2004 and 2017, showed no inkling of a long-lived formation, either. The Hubble data confirmed the feature’s presence back to 2023.”

The wave sits within one of Saturn’s powerful jet streams and extends through multiple layers of the atmosphere, indicating it is not just a cloud-level feature, but a vertically extended atmospheric structure. The decagon’s apparent position shifts slightly, because Hubble captures images from different wavelengths. Those different wavelengths probe different altitudes in Saturn’s atmosphere.

“The most intriguing part to me is that this seems to have just formed recently,” said Simon. “The question is, why did it suddenly form now when we haven’t seen one before?” 

The authors say further study is needed from Hubble and NASA’s James Webb Space Telescope, as well as analysis of computer models, to understand how the decagon formed, how long it may last, and how it compares to the long-lived hexagon in the north.

Hubble’s long duration in operation has allowed astronomers to track changes over time in solar system planets and other astronomical objects as well.

Rather than providing a single snapshot, the OPAL program allows scientists to follow seasonal changes, track short-lived storms, and identify other atmospheric features that evolve slowly over time.

“When we started the OPAL program, we expected compelling surprises, but we didn’t know what to expect specifically,” said Mike Wong, study co-author, University of California, Berkeley. “A lot of the discoveries we see coming from OPAL are not just based on one observation, but on years and years of data. Regular observations over time are enabling a lot of new findings.”

The team plans to continue observing Saturn to determine whether the decagon settles into a long-lived, stable configuration like the northern hexagon or continues to evolve. Future observations also could help scientists determine what drives the wave, what it reveals about the atmospheric dynamics of giant planets throughout the solar system, and how they may relate to those we see here on Earth.

The Hubble Space Telescope has been operating for more than three decades and continues to make ground-breaking discoveries that shape our fundamental understanding of the universe. Hubble is a project of international cooperation between NASA and ESA (European Space Agency). NASA’s Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope and mission operations. Lockheed Martin Space also supports mission operations at Goddard. The Space Telescope Science Institute in Baltimore, which is operated by the Association of Universities for Research in Astronomy, conducts Hubble science operations for NASA.

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Brilliant Venus and a Harvest Moon

Use the Moon to find Antares and the Teapot, spot brilliant Venus, welcome the equinox, and see the Harvest Moon near Saturn and Neptune.

Skywatching Highlights

• Sept. 14-20: Use the Moon to find Antares and the Teapot; dark skies may reveal the Milky Way center
• Sept 18: Venus reaches peak brilliance for this evening appearance
• Sept. 22: September equinox; fall begins in the Northern Hemisphere and spring in the Southern Hemisphere
• Sept. 26: Harvest Moon rises near Saturn and Neptune

Transcript

The Moon joins a tea party… Venus cranks up the brightness… the seasons officially change… and the Harvest Moon meets up with some planetary neighbors.

That’s What’s Up for September.

From September 14 through 20, let the Moon guide you to a few celestial landmarks. About an hour after sunset, look south to find the Moon in the evening sky.

Night by night, the Moon shifts position against the background stars, passing near Antares.

This bright, reddish star marks the heart of the constellation Scorpius.

Next you’ll see the Teapot, a group of stars in neighboring Sagittarius that really does resemble a teapot, complete with a handle, lid, and spout.

If you are under an especially dark sky… you may see hazy steam rising from the Teapot’s spout.
Follow that steam to its thickest part, and you’ll be looking toward the center of our Milky Way galaxy.

Look west on September 18 as Venus hits peak brilliance, shining at its brightest of this evening appearance..

You won’t have to search hard to find it. Shortly after sunset, Venus will stand out as a brilliant point of light low above the western horizon, outshining every star around it. A clear view of the horizon will give you the best chance to catch it before it sets.

On September 19, celebrate International Observe the Moon Night!

People around the world are invited to look up and connect with our nearest celestial neighbor while learning more about lunar science, exploration, and the many ways the Moon has shaped cultures around the world. Find an event near you — or learn how to participate from wherever you are — at go.nasa.gov/ObserveTheMoon.

Then on September 22, it’s officially fall in the Northern Hemisphere …while spring begins in the Southern Hemisphere.

That’s the September equinox, when the Sun is directly above Earth’s equator and day and night are close to equal in length around the world.

From there, daylight keeps getting shorter in the Northern Hemisphere and longer in the Southern Hemisphere.

And on September 26, the Harvest Moon takes center stage, rising in the east shortly after sunset.

It won’t be alone. Saturn appears nearby, with faint Neptune completing a wide triangle in the sky.

Saturn is the easy one-you can see it with just your eyes. Neptune is a bit more challenging. At around magnitude 8, it’s too faint to see with the unaided eye …so you’ll need binoculars or a telescope to spot it. Darker skies and good observing conditions can help bring it into view.

Here are the phases of the Moon for September.

You can stay up to date on all of NASA’s missions exploring the solar system and beyond at NASA Science. I’m Raquel Villanueva from NASA’s Jet Propulsion Laboratory, and that’s What’s Up this month.

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For the first time in more than 30 years, NASA has no firm plans to send any new landers or rovers to Mars. Instead, the agency's near-term focus at the red planet is on aerial drones, a pioneering mode of exploration that didn't seem realistic until a few years ago.

The first real use of drones for science at Mars will come with the SkyFall mission, a fleet of three helicopters set for launch as soon as late 2028. SkyFall's helicopters will ride to the red planet with NASA's Space Reactor-1 "Freedom" mission, which has the primary objective of demonstrating nuclear electric propulsion in deep space.

The launch schedule is aggressive for SR-1 Freedom and SkyFall, projects that didn't even exist in NASA's portfolio six months ago. NASA's plan for the SR-1 Freedom mission, estimated to cost $2.1 billion, calls for repurposing the core module of the canceled Gateway lunar space station into a testbed for nuclear electric propulsion. SkyFall will build on NASA's success with the Ingenuity helicopter, an experimental vehicle that became the first rotorcraft to fly on another world in 2021.

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At the center of our solar system, the Sun influences every planet that orbits it. In two recent NASA-funded studies, scientists uncovered how ancient events in the Sun’s history may have helped create Earth’s unique climate and driven previously unexplained climatic shifts.  

In new research, scientists at NASA’s SHIELD (Solar Wind with Hydrogen Ion charge Exchange and Large-Scale Dynamics) center — one of NASA’s DRIVE (Diversify, Realize, Integrate, Venture, Educate) Science Centers — trace the trajectory of the heliosphere, the massive bubble created by our Sun that envelops our solar system, as it moved through our galaxy and influenced Earth’s climate along the way. In another paper, a NASA scientist and coauthors investigate how the younger, dimmer Sun managed to heat Earth by seeding the production of potent greenhouse gases.

A Sun on the move 

Over the last tens of millions of years, Earth’s climate has undergone significant shifts, including notable ice ages in which the global average temperature temporarily dropped by several degrees. During these periods, more frequent climate swings led Earth to warm and cool. To explain these periods of warming and cooling, scientists looked to factors internal to Earth, including orbital changes, greenhouse gases, and ice. But new research suggests changes to the Sun’s environment may be key to understanding Earth’s temperature swings. 

Just as our planet is encased by an atmosphere, so our entire solar system is encased inside a kind of “atmosphere” created by the Sun. This protective bubble, known as the heliosphere, is formed by a continuous solar wind of charged particles streaming out from the Sun in all directions. 

Our heliosphere orbits around the center of our galaxy, the Milky Way. Throughout the Sun’s 4.6-billion-year existence, our heliosphere has traversed various regions within our galaxy. In a paper published on Aug. 21 in Annual Review of Astronomy and Astrophysics, researchers at NASA’s SHIELD used computer modeling to reverse-engineer the path of the heliosphere through our galaxy, revealing that the environments it passed through may have triggered changes on Earth.   

Merav Opher, SHIELD’s principal investigator at Boston University, and her team ran simulations that showed the Sun has encountered frigid expanses of gas and dust at least three different times in the past few million years. In these instances, massive interstellar “cold clouds” pushed against the heliosphere to such an extent that it shrank to smaller than Earth’s orbit, stranding our planet outside the Sun’s protective shield. 

These exposures — approximately 2 to 3 million years, 6 to 7 million years, and 13 to 14 million years ago — would have exposed Earth’s atmosphere to totally different surroundings. The simulation results match geologic evidence: Elements prevalent in interstellar dust appear in deep-sea sediment core samples, Antarctic snow, and lunar samples during these timelines. 

These heliosphere collapse events may also explain ancient climatic patterns on Earth. In the simulations, when Earth’s atmosphere was exposed to a cold, dense galactic hydrogen cloud, it increased water vapor content and shifted upper-atmospheric dynamics, ultimately altering the conditions at the surface. In summary, our heliosphere’s trips through colder regions in our galaxy may be a key factor in driving some of Earth’s ancient changes in climate, including possible ice ages.  

Next frontier in studying heliophysics 

The SHIELD center is one of several that NASA funds to unlock the next generation of heliospheric research. As a DRIVE Science Center, SHIELD builds a team of researchers with differing expertise, approaches, and opinions to develop a model, or “digital twin,” of the heliosphere that helps reveal how the heliosphere interacts with its surroundings, including dense interstellar clouds. Understanding our unique, habitable solar system will help unravel the mysteries of life’s evolution on Earth and potentially uncover other habitable star systems. 

Young Sun 

In another paper, Vladimir Airapetian, a scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, focuses on a long-standing mystery of how the ancient Sun warmed early Earth enough to sustain life. Three billion years ago, the young Sun was 70% as bright as it is today. Under these dimmer conditions, Earth should have been frozen solid. Yet geological evidence shows stable liquid water already existed long before that. This puzzle — a balmy Earth under a cooler, dimmer Sun — is known as the Faint Young Sun paradox.  

One clue to resolving the paradox comes from young Sun-like stars elsewhere in the galaxy. These “toddler” stars are prone to throwing fits. Specifically, data from NASA’s retired Kepler space telescope shows that young Sun-like stars regularly erupt with massive superflares, flinging high-energy particles in all directions on a daily basis. If our young Sun was like these other stars, Airapetian proposes, the barrage of high-energy solar particles could have triggered chemical reactions that were key to warming early Earth. 

Airapetian’s team simulated early Earth’s atmosphere in a sealed chamber, mixing molecular nitrogen, ammonia, carbon dioxide, and carbon monoxide. They then fired protons into the mixture, simulating the onslaught of particles from superflares. This proton bombardment triggered several changes including the production of nitrous oxide, a greenhouse gas 300 times more potent than carbon dioxide. The research was published in Astrophysical Journal Letters.

This nitrous oxide could help Earth hold onto heat. But not all the nitrous oxide would last. The young Sun’s intense ultraviolet radiation would break some of it down, splitting the molecule back into nitrogen and oxygen. But even if only 10% of the nitrous observed in the experiment survived, Airapetian’s team’s computer simulations confirmed, it would still warm Earth’s equatorial regions to about 41 degrees Fahrenheit (5 degrees Celsius), above water’s freezing point. This smaller amount of nitrous could even accelerate prebiotic synthesis: just-above-freezing temperatures have been found to be more efficient for building complex chains of amino acids than warmer temperatures. 

Unearthing secrets of our star-planet system 

Together, these two studies show that the Sun can lead to surprising implications for Earth. While our planet stands alone in many ways, it was formed and has always existed as part of a star-planet system. Understanding that unique relationship promises new insights about both Earth and the star that sustains it.  

By Desiree Apodaca and Miles Hatfield 
NASA’s Goddard Space Flight Center, Greenbelt, Md. 

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Between Aug. 11 and 12, NASA’s Lunar Reconnaissance Orbiter (LRO) captured a series of images of a new crater on the Moon. The crater formed on Aug. 5, when a SpaceX Falcon 9 upper stage impacted the surface following its January 2025 launch of the Firefly Blue Ghost 1 mission.

To capture imagery of the impact, engineers tilted the spacecraft so its cameras would point toward the crater each time LRO passed about 60 miles above the Moon, traveling 1 mile per second. The orbiter circles the Moon from pole to pole every two hours, while the Moon slowly rotates underneath it. To photograph a specific spot, the spacecraft must wait until that location turns into view, which took six days in this case.

Getting the pointing right was only half the challenge; timing had to be accurate as well. If the camera snapped even 10 seconds too early or too late, the target would drift off-center by 10 miles.

Because of the variety of viewing angles, scientists could see the crater under multiple lighting conditions that revealed unique features. In images where the crater rim stood out, scientists measured its 60‑foot width. Scientists also determined the crater is less than 10 feet deep based on the length of its shadow.

To capture these details, LRO used its Narrow-Angle Camera, which can spot features as small as 3 feet wide.

The images above show bright and dark rays stretching out from the crater. The darker streaks are made of surface dust and rocks altered over a long time by solar wind, galactic cosmic rays, and micrometeorite impacts. This weathered material was excavated by the collision from 1.5 feet into the lunar surface. The brighter streaks near the crater rim are made of fresh material excavated from deeper underground.

Finding the impact site took global coordination among experts and hobbyists. Independent astronomers first identified the rocket’s trajectory using publicly available data. NASA’s Center for Near Earth Object Studies, which tracks natural objects that could pose hazards to Earth for the agency’s Planetary Defense program, used this opportunity to test and validate tools and techniques for predicting impacts.

Based at NASA’s Jet Propulsion Laboratory in Southern California, the center incrementally refined the trajectory until identifying the location of impact, which it provided to the Republic of Korea for their Korea Pathfinder Lunar Orbiter (Danuri) team. The team used the high-resolution LUTI camera on Danuri a few hours later to image the crater, finding the prediction was accurate to about 0.6 miles. 

After capturing images of the crater, the Danuri mission sent coordinates to NASA’s LRO team to help refine their follow-up imaging sequence. Comparing their new crater images with the pre-impact images, the LRO team updated the crater center coordinates: 19.4759°N, 266.7138°E, 511 meters elevation.

About the Author

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Earth and the Martian moon Phobos dance together in a series of images recently acquired by NASA’s Perseverance Mars rover. Earth appears as a point of light in the Martian sky, disappearing behind the crescent of Phobos, the larger of Mars’ two moons.

This is the first time humanity has captured from the surface of another planet an observation of Earth disappearing behind an object.

The image sequence was taken by the rover’s Mastcam-Z instrument at about 7 p.m. local solar time (the Martian evening time where the rover is located) on July 2, the 1,907th Martian day, or sol, of the mission. In the composite image, Earth travels from the upper left of the frame toward the lower right while Phobos, moving from lower left to upper right, sweeps across its path. In the third frame of the sequence, the two meet, and our planet winks out behind the little moon’s shadowed edge.

“The composite image makes for a unique Earth self-portrait, taken from the surface of another planet, with a Phobos photobomb,” said Justin Maki, the Mastcam-Z deputy principal investigator and imaging scientist for Perseverance at NASA’s Jet Propulsion Laboratory in Southern California.

From where Perseverance sits on the rim of Mars’ Jezero Crater, the two objects could hardly look more different. Phobos, a lumpy, potato-shaped moon about 17 miles (27 kilometers) across at its widest, orbits so close to Mars (4,850 miles, or 7,800 kilometers, away) that when the images were taken, Phobos appears roughly one-third the width of Earth’s Moon as seen from our planet. Some 195 million miles (314 million kilometers) away at the time, Earth is reduced to a single, pixel-size dot.

“Phobos crosses the Martian sky three times a day, and Earth is visible for months at a stretch, but catching one directly behind the other takes planning and a little luck,” said Mark Lemmon, a Mastcam-Z co-investigator at the Space Science Institute in Boulder, Colorado, who planned the observation and assembled the composite.

Transits, occultations, eclipses

Astronomers call the event captured in this observation an occultation: when a larger-appearing body completely blocks the one behind it from the viewer’s standpoint. By contrast, an eclipse occurs when one object moves into the shadow of another. When the Moon passes through Earth’s shadow, it’s called a lunar eclipse; when one object that appears to be the same size as another blocks it, like when the Moon passes before the Sun, it’s known as a solar eclipse.

When the roles are reversed, with a smaller-looking object crossing the face of a larger-looking one, astronomers call that a transit. Perseverance has observed those, too: when Phobos or Deimos crosses the disk of the Sun as seen from Mars. These are sometimes described informally as “Martian solar eclipses.”

More about Perseverance

NASA’s Jet Propulsion Laboratory in Southern California, which is managed by Caltech, built and manages operations of the Perseverance rover on behalf of the agency’s Science Mission Directorate in Washington, as part of NASA’s Mars Exploration Program portfolio. Arizona State University leads the operations of the rover’s Mastcam-Z instrument, working in collaboration with Malin Space Science Systems in San Diego, on the design, fabrication, testing, and operation of the cameras.

For more about Perseverance:

https://science.nasa.gov/mission/mars-2020-perseverance

News Media Contacts

DC Agle
 
Jet Propulsion Laboratory, Pasadena, Calif.
818-393-9011

agle@jpl.nasa.gov 

Karen Fox / Alana Johnson
NASA Headquarters, Washington 
240-285-5155 / 202-672-4780
karen.c.fox@nasa.gov / alana.r.johnson@nasa.gov 

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