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NASA’s SPHEREx Observatory Completes First Cosmic Map Like No Other

✇NASA Breaking News
By: scarney1

6 min read

Preparations for Next Moonwalk Simulations Underway (and Underwater)

This panoramic view of SPHEREx’s first all-sky map shows how the sky looks to the telescope. It transitions between observations of colors emitted by hot hydrogen gas (blue) and cosmic dust (red), and those primarily emitted by stars.
Credit: NASA/JPL-Caltech

Launched in March, NASA’s SPHEREx space telescope has completed its first infrared map of the entire sky in 102 colors. While not visible to the human eye, these 102 infrared wavelengths of light are prevalent in the cosmos, and observing the entire sky this way enables scientists to answer big questions, including how a dramatic event that occurred in the first billionth of a trillionth of a trillionth of a second after the big bang influenced the 3D distribution of hundreds of millions of galaxies in our universe. In addition, scientists will use the data to study how galaxies have changed over the universe’s nearly 14 billion-year history and learn about the distribution of key ingredients for life in our own galaxy.  

“It’s incredible how much information SPHEREx has collected in just six months — information that will be especially valuable when used alongside our other missions’ data to better understand our universe,” said Shawn Domagal-Goldman, director of the Astrophysics Division at NASA Headquarters in Washington. “We essentially have 102 new maps of the entire sky, each one in a different wavelength and containing unique information about the objects it sees. I think every astronomer is going to find something of value here, as NASA’s missions enable the world to answer fundamental questions about how the universe got its start, and how it changed to eventually create a home for us in it.” 

Circling Earth about 14½ times a day, SPHEREx (which stands for Spectro-Photometer for the History of the Universe, Epoch of Reionization, and Ices Explorer) travels from north to south, passing over the poles. Each day it takes about 3,600 images along one circular strip of the sky, and as the days pass and the planet moves around the Sun, SPHEREx’s field of view shifts as well. After six months, the observatory has looked out into space in every direction, capturing the entire sky in 360 degrees. 

Managed by NASA’s Jet Propulsion Laboratory in Southern California, the mission began mapping the sky in May and completed its first all-sky mosaic in December. It will complete three additional all-sky scans during its two-year primary mission, and merging those maps together will increase the sensitivity of the measurements. The entire dataset is freely available to scientists and the public.  

“SPHEREx is a mid-sized astrophysics mission delivering big science,” said JPL Director Dave Gallagher. “It’s a phenomenal example of how we turn bold ideas into reality, and in doing so, unlock enormous potential for discovery.”  

NASA’s SPHEREx has mapped the entire sky in 102 infrared colors, which are invisible to the human eye but can be used to reveal different features of the cosmos. This image features a selection of colors emitted primarily by stars (blue, green, and white), hot hydrogen gas (blue), and cosmic dust (red).
NASA/JPL-Caltech
This SPHEREx image shows a selection of the infrared colors primarily emitted by stars and galaxies. The space telescope is observing hundreds of millions of distant galaxies across the sky. Its multiwavelength view will help astronomers measure the distance to those galaxies.
NASA/JPL-Caltech
The infrared colors emitted primarily by dust (red) and hot gas (blue), key ingredients for forming new stars and planets, are seen in this SPHEREx image. Though these clouds of material cover a massive portion of the sky, they are invisible in most wavelengths of light, including those the human eye can detect.
NASA/JPL-Caltech

Superpowered telescope 

Each of the 102 colors detected by SPHEREx represents a wavelength of infrared light, and each wavelength provides unique information about the galaxies, stars, planet-forming regions, and other cosmic features therein. For example, dense clouds of dust in our galaxy where stars and planets form radiate brightly in certain wavelengths but emit no light (and are therefore totally invisible) in others. The process of separating the light from a source into its component wavelengths is called spectroscopy.  

And while a handful of previous missions has also mapped the entire sky, such as NASA’s Wide-field Infrared Survey Explorer, none have done so in nearly as many colors as SPHEREx. By contrast, NASA’s James Webb Space Telescope can do spectroscopy with significantly more wavelengths of light than SPHEREx, but with a field of view thousands of times smaller. The combination of colors and such a wide field of view is why SPHEREx is so powerful. 

“The superpower of SPHEREx is that it captures the whole sky in 102 colors about every six months. That’s an amazing amount of information to gather in a short amount of time,” said Beth Fabinsky, the SPHEREx project manager at JPL. “I think this makes us the mantis shrimp of telescopes, because we have an amazing multicolor visual detection system and we can also see a very wide swath of our surroundings.” 

To accomplish this feat, SPHEREx uses six detectors, each paired with a specially designed filter that contains a gradient of 17 colors. That means every image taken with those six detectors contains 102 colors (six times 17). It also means that every all-sky map that SPHEREx produces is really 102 maps, each in a different color.  

The observatory will use those colors to measure the distance to hundreds of millions of galaxies. Though the positions of most of those galaxies have already been mapped in two dimensions by other observatories, SPHEREx’s map will be in 3D, enabling scientists to measure subtle variations in the way galaxies are clustered and distributed across the universe.  

Each frame of this movie shows the entire sky in a different infrared wavelength, indicated by the color bar in the top right corner. Taken by NASA’s SPHEREx observatory, the maps illustrate how viewing the universe in different wavelengths of light can reveal unique cosmic features.
Credit: NASA/JPL-Caltech

Those measurements will offer insights into an event that took place in the first billionth of a trillionth of a trillionth of a second after the big bang. In this moment, called inflation, the universe expanded by a trillion-trillionfold. Nothing like it has occurred in the universe since, and scientists want to understand it better. The SPHEREx mission’s approach is one way to help in that effort. 

More about SPHEREx 

The SPHEREx mission is managed by JPL for NASA’s Astrophysics Division within the Science Mission Directorate in Washington. The telescope and the spacecraft bus were built by BAE Systems. The science analysis of the SPHEREx data is being conducted by a team of scientists at 10 institutions across the U.S., and in South Korea and Taiwan. Data is processed and archived at IPAC at Caltech in Pasadena, which manages JPL for NASA. The mission’s principal investigator is based at Caltech with a joint JPL appointment. The SPHEREx dataset is publicly available. 

For more information about the SPHEREx mission visit: 

https://science.nasa.gov/mission/spherex/

News Media Contacts

Calla Cofield 
Jet Propulsion Laboratory, Pasadena, Calif. 
626-808-2469 
calla.e.cofield@jpl.nasa.gov 

2025-144

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Each frame of this movie shows the entire sky in a different infrared wavelength, indicated by the widget in the top right corner. Taken by NASA’s SPHEREx ob...

NASA Study Suggests Saturn’s Moon Titan May Not Have Global Ocean

✇NASA Breaking News
By: scarney1

6 min read

Preparations for Next Moonwalk Simulations Underway (and Underwater)

Artist's rendering of NASA's Cassini spacecraft observing a sunset through Titan's hazy atmosphere. Against the blackness of space, the moon is backlit, with a ring of white and a ring of blue light marking its outer edge, with the Sun as a point of bright light peeking from the upper-right edge of the disc. Cassini is dimly lit in the foreground partially blocking the moon, a dull gold with a large white antenna dish, and three spindly protrusions coming out of its center at 90-degree angles to each other.
This artist’s concept depicts NASA’s Cassini spacecraft performing one of its many close flybys of Titan, Saturn’s largest moon. By analyzing the Doppler shift of radio signals traveling to and from Earth, the mission precisely measured Titan’s gravity field.
NASA/JPL-Caltech

A key discovery from NASA’s Cassini mission in 2008 was that Saturn’s largest moon Titan may have a vast water ocean below its hydrocarbon-rich surface. But reanalysis of mission data suggests a more complicated picture: Titan’s interior is more likely composed of ice, with layers of slush and small pockets of warm water that form near its rocky core.  

Led by researchers at NASA’s Jet Propulsion Laboratory in Southern California and published in the journal Nature on Wednesday, the new study could have implications for scientists’ understanding of Titan and other icy moons throughout our solar system. 

“This research underscores the power of archival planetary science data. It is important to remember that the data these amazing spacecraft collect lives on so discoveries can be made years, or even decades, later as analysis techniques get more sophisticated,” said Julie Castillo-Rogez, senior research scientist at JPL and a coauthor of the study. “It’s the gift that keeps giving.” 

To remotely probe planets, moons, and asteroids, scientists study the radio frequency communications traveling back and forth between spacecraft and NASA’s Deep Space Network. It’s a multilayered process. Because a moon’s body may not have a uniform distribution of mass, its gravity field will change as a spacecraft flies through it, causing the spacecraft to speed up or slow down slightly. In turn, these variations in speed alter the frequency of the radio waves going to and from the spacecraft — an effect known as Doppler shift. Analyzing the Doppler shift can lend insight into a moon’s gravity field and its shape, which can change over time as it orbits within its parent planet’s gravitational pull. 

This shape shifting is called tidal flexing. In Titan’s case, Saturn’s immense gravitational field squeezes the moon when Titan is closer to the planet during its slightly elliptical orbit, and it stretches the moon when it is farthest. Such flexing creates energy that is lost, or dissipated, in the form of internal heating. 

When mission scientists analyzed radio-frequency data gathered during the now-retired Cassini mission’s 10 close approaches of Titan, they found the moon to be flexing so much that they concluded it must have a liquid interior, since a solid interior would have flexed far less. (Think of a balloon filled with water versus a billiard ball.)  

New technique 

The new research highlights another possible explanation for this malleability: an interior composed of layers featuring a mix of ice and water that allows the moon to flex. In this scenario, there would be a lag of several hours between Saturn’s tidal pull and when the moon shows signs of flexing — much slower than if the interior were fully liquid. A slushy interior would also exhibit a stronger energy dissipation signature in the moon’s gravity field than a liquid one, because these slush layers would generate friction and produce heat when the ice crystals rub against one another. But there was nothing apparent in the data to suggest this was happening. 

So the study authors, led by JPL postdoctoral researcher Flavio Petricca, looked more closely at the Doppler data to see why. By applying a novel processing technique, they reduced the noise in the data. What emerged was a signature that revealed strong energy loss deep inside Titan. The researchers interpreted this signature to be coming from layers of slush, overlaid by a thick shell of solid ice. 

Based on this new model of Titan’s interior, the researchers suggest that the only liquid would be in the form of pockets of meltwater. Heated by dissipating tidal energy, the water pockets slowly travel toward the frozen layers of ice at the surface. As they rise, they have the potential to create unique environments enriched by organic molecules being supplied from below and from material delivered via meteorite impacts on the surface.  

“Nobody was expecting very strong energy dissipation inside Titan. But by reducing the noise in the Doppler data, we could see these smaller wiggles emerge. That was the smoking gun that indicates Titan’s interior is different from what was inferred from previous analyses,” said Petricca. “The low viscosity of the slush still allows the moon to bulge and compress in response to Saturn’s tides, and to remove the heat that would otherwise melt the ice and form an ocean.” 

Potential for life 

“While Titan may not possess a global ocean, that doesn’t preclude its potential for harboring basic life forms, assuming life could form on Titan. In fact, I think it makes Titan more interesting,” Petricca added. “Our analysis shows there should be pockets of liquid water, possibly as warm as 20 degrees Celsius (68 degrees Fahrenheit), cycling nutrients from the moon’s rocky core through slushy layers of high-pressure ice to a solid icy shell at the surface.” 

More definitive information could come from NASA’s next mission to Saturn. Launching no earlier than 2028, the agency’s Dragonfly mission to the hazy moon could provide the ground truth. The first-of-its-kind rotorcraft will explore Titan’s surface to investigate the moon’s habitability. Carrying a seismometer, the mission may provide key measurements to probe Titan’s interior, depending on what seismic events occur while it is on the surface. 

More about Cassini 

The Cassini-Huygens mission was a cooperative project of NASA, ESA (European Space Agency), and the Italian Space Agency. A division of Caltech in Pasadena, JPL managed the mission for NASA’s Space Mission Directorate in Washington and designed, developed, and assembled the Cassini orbiter. 

To learn more about NASA’s Cassini mission, visit:

https://science.nasa.gov/mission/cassini/

News Media Contacts 

Ian J. O’Neill 
Jet Propulsion Laboratory, Pasadena, Calif. 
818-354-2649 
ian.j.oneill@jpl.nasa.gov 

Karen Fox / Alana Johnson 
NASA Headquarters, Washington
202-358-1600 / 202-358-1501 
karen.c.fox@nasa.gov / alana.r.johnson@nasa.gov 

2025-142

NASA JPL Shakes Things Up Testing Future Commercial Lunar Spacecraft

✇NASA Breaking News
By: scarney1

6 min read

Preparations for Next Moonwalk Simulations Underway (and Underwater)

A time-lapse video recorded at JPL in October shows engineers and technicians moving and attaching a full-scale model of Firefly Aerospace’s Blue Ghost lunar lander on top of two lunar orbiters. The full stack was then subjected to a vibration test that mimics the violent action of rocket launch.
NASA/JPL-Caltech

The same historic facilities that some 50 years ago prepared NASA’s twin Voyager probes for their ongoing interstellar odyssey are helping to ready a towering commercial spacecraft for a journey to the Moon. Launches involve brutal shaking and astonishingly loud noises, and testing in these facilities mimics those conditions to help ensure mission hardware can survive the ordeal. The latest spacecraft to get this treatment are Firefly Aerospace’s Blue Ghost Mission 2 vehicles, set to launch to the Moon’s far side next year. 

The Environmental Test Laboratory at NASA’s Jet Propulsion Laboratory in Southern California is where dozens of robotic spacecraft have been subjected to powerful jolts, extended rattling, high-decibel blasts of sound, and frigid and scorching temperatures, among other trials. Constructed in the 1960s and modernized over the years, the facilities have prepared every NASA spacecraft built or assembled at JPL for the rigors of space, from the Ranger spacecraft of the dawning Space Age to the Perseverance Mars rover to Europa Clipper, currently en route to the Jupiter system.  

That legacy, and the decades of accumulated experience of the Environmental Test Laboratory team at JPL, is also supporting industry efforts to return to the Moon as part of NASA’s CLPS (Commercial Lunar Payload Services) initiative and its Artemis campaign, which will bring astronauts back to the lunar surface.  

In recent months, a full-scale model of Firefly’s uncrewed Blue Ghost Mission 2 spacecraft was put through its paces by the experts in the lab’s vibration and acoustic testing facilities. Lessons learned with this model, called a structural qualification unit, will be applied to upcoming testing of the spacecraft that will fly to the Moon as early as 2026 through NASA’s CLPS. 

“There’s a lot of knowledge gained over the years, passed from one generation of JPL engineers to another, that we bring to bear to support our own missions as well as commercial efforts,” said Michel William, a JPL engineer in the Environmental Test Laboratory who led the testing. “The little details that go into getting these tests right — nobody teaches you that in school, and it’s such a critical piece of space launch.”  

Engineers and technicians secure a full-scale model of Firefly’s Blue Ghost lunar lander atop the other spacecraft that make up the company’s second delivery to the lunar surface. Environmental testing for the spacecraft took place in a clean room at NASA’s Jet Propulsion Laboratory in October.
NASA/JPL-Caltech

Testing just right 

The Environmental Test Laboratory team led environmental testing for Firefly’s Blue Ghost Mission 1 lander in 2024, and seeing the spacecraft achieve a soft Moon landing in March was a point of pride for them. Firefly’s next CLPS delivery debuts a dual-spacecraft configuration and hosts multiple international payloads, with the company’s Elytra Dark orbital vehicle stacked below the Blue Ghost lunar lander. Standing 22 feet (6.9 meters) high, the full structure is more than three times as tall as the Mission 1 lander. 

This fall, a structural qualification model of the full stack was clamped to a “shaker table” inside a clean room at JPL and repeatedly rattled in three directions while hundreds of sensors monitored the rapid movement. Then, inside a separate acoustic testing chamber, giant horns blared at it from openings built into the room’s 16-inch-thick (41-centimeter-thick) concrete walls. The horns use compressed nitrogen gas to pummel spacecraft with up to 153 decibels, noise loud enough to cause permanent hearing loss in a human.  

Each type of test involves several increasingly intense iterations. Between rounds, JPL’s dynamics environment experts analyze the data to compare what the spacecraft experienced to computer model predictions. Sometimes a discrepancy leads to hardware modifications, sometimes a tweak to the computer model. Engineers and technicians are careful to push the hardware, but not too far. 

“You can either under-test or over-test, and both are bad,” William said. “If you over-test, you can break your hardware. If you under-test, it can break on the rocket. It’s a fine line.” 

Since the model isn’t itself launching to the Moon, Firefly’s recent Environmental Test Laboratory visit didn’t include several types of trials that are generally completed only for flight hardware. A launchpad-bound spacecraft would undergo electromagnetic testing to ensure that signals from its electronic parts don’t interfere with one another. And, in what is probably the most well-known environmental test, flight-bound hardware is baked or chilled at extreme temperatures in a thermal vacuum chamber from which all the air is sucked out. The multiple thermal vacuum chamber facilities at JPL include two large historic “space simulators” built within NASA’s first few years of existence: a chamber that’s 10 feet in diameter and another that’s 25 feet across. 

A full-scale model of Firefly Aerospace’s Blue Ghost Mission 2 lunar lander is prepared for delivery into a clean room at JPL’s Environmental Test Laboratory in September.
NASA/JPL-Caltech
Technicians and engineers at JPL ready a fixture that will attach a full-scale model of Firefly Aerospace’s Blue Ghost Mission 2 lunar lander, visible in the background, to a “shaker table” that tests a spacecraft’s readiness to survive the stresses of launch.
NASA/JPL-Caltech

Qualifying for launch 

The completion of Environmental Test Laboratory testing on Firefly’s structural qualification model helps prove the spacecraft will survive its ride out of Earth’s atmosphere aboard a SpaceX Falcon 9 rocket. Firefly’s Blue Ghost Mission 2 team is now turning its focus to completing assembly and testing of the flight hardware for launch. 

Once at the Moon, the Blue Ghost lander will touch down on the far side, delivering its payloads to the surface. Those include LuSEE-Night, a radio telescope that is a joint effort by NASA, the U.S. Department of Energy, and University of California, Berkeley’s Space Sciences Laboratory. A payload developed at JPL called User Terminal will test a compact, low-cost S-band radio communications system that could enable future far-side missions to talk to each other and to relay orbiters.  

Meantime, Firefly’s Elytra Dark orbital vehicle will have deployed into lunar orbit ESA’s (European Space Agency’s) Lunar Pathfinder communications satellite — a payload on which NASA is collaborating. Both vehicles will remain in orbit and able to relay data from the far-side surface back to Earth.  

“Firefly’s Blue Ghost Mission 2 will deliver both NASA and international commercial payloads to further prove out technologies for Artemis and help enable a long-term presence on the Moon,” said Ray Allensworth, Firefly’s spacecraft program director. “The extensive spacecraft environmental testing we did at JPL for Mission 1 was a critical step in Firefly’s test campaign for our historic lunar mission. Now we’re collaborating again to support a successful repeat on the Moon that will unlock even more insights for future robotic and human missions.” 

News Media Contact 

Melissa Pamer 
Jet Propulsion Laboratory, Pasadena, Calif. 
626-314-4928 
melissa.pamer@jpl.nasa.gov 

2025-141

One of NASA’s Key Cameras Orbiting Mars Takes 100,000th Image

✇NASA Breaking News
By: scarney1

3 min read

Preparations for Next Moonwalk Simulations Underway (and Underwater)

An overhead color view of the Martian surface shows rough and varied terrain in shades ranging from golden tan to electric blue. At upper left, the ground appears more flat and cratered than other areas of the image, and is colored dark grayish-blue with highlights of silver and tan. The upper right corner of the image looks like wavy sand dunes, in shades of dark blue with bright silvery highlights, except for one apparent ridgeline that stands out as an elongated S-shape in electric blue. The bottom half of the image shows more mountainous terrain that gets lighter and more gold-colored nearer the bottom of the frame. A pair of smooth valleys run diagonally between the peaks, from around the center of the image toward the bottom-left corner; the upper one is a shade of silvery blue and the bottom one is a grayish-gold, and both have ridges lining their upper walls, looking like lines of sharp teeth biting into the valleys.
This view of a region called Syrtis Major is from the 100,000th image captured by NASA’s Mars Reconnaissance Orbiter using its HiRISE camera. Over nearly 20 years, HiRISE has helped scientists understand how the Red Planet’s surface is constantly changing.
NASA/JPL-Caltech/University of Arizona

Mesas and dunes stand out in the view snapped by HiRISE, one of the imagers aboard the agency’s Mars Reconnaissance Orbiter.

After nearly 20 years at the Red Planet, NASA’s Mars Reconnaissance Orbiter (MRO) has snapped its 100,000th image of the surface with its HiRISE camera. Short for High Resolution Imaging Science Experiment, HiRISE is the instrument the mission relies on for high-resolution images of features ranging from impact craters, sand dunes, and ice deposits to potential landing sites. Those images, in turn, help improve our understanding of Mars and prepare for NASA’s future human missions there. 

Captured Oct. 7, this milestone image from the spacecraft shows mesas and dunes within Syrtis Major, a region about 50 miles (80 kilometers) southeast of Jezero Crater, which NASA’s Perseverance rover is exploring. Scientists are analyzing the image to better understand the source of windblown sand that gets trapped in the region’s landscape, eventually forming dunes. 

“HiRISE hasn’t just discovered how different the Martian surface is from Earth, it’s also shown us how that surface changes over time,” said MRO’s project scientist, Leslie Tamppari of NASA’s Jet Propulsion Laboratory in Southern California. “We’ve seen dune fields marching along with the wind and avalanches careening down steep slopes.” 

Watch highlights of images captured by HiRISE, the high-resolution camera aboard NASA’s Mars Reconnaissance Orbiter, including its 100,000th image, showing the plains and dunes of Syrtis Major.
NASA/JPL-Caltech/University of Arizona

The subject of the 100,000th image was recommended by a high school student through the HiWish site, where anyone can suggest parts of the planet to study. Team members at University of Arizona in Tucson, which operates the camera, also make 3D models of HiRISE imagery so that viewers can experience virtual flyover videos. 

“Rapid data releases, as well as imaging targets suggested by the broader science community and public, have been a hallmark of HiRISE,” said the camera’s principal investigator, Shane Byrne of the University of Arizona in Tucson. “One hundred thousand images just like this one have made Mars more familiar and accessible for everyone.” 

More about MRO 

NASA’s Jet Propulsion Laboratory in Southern California manages MRO for NASA’s Science Mission Directorate in Washington as part of NASA’s Mars Exploration Program portfolio. Lockheed Martin Space in Denver built MRO and supports its operations. 

The University of Arizona in Tucson operates HiRISE, which was built by Ball Aerospace & Technologies Corp., in Boulder, Colorado. 

For more information, visit:

https://science.nasa.gov/mission/mars-reconnaissance-orbiter

News Media Contacts

Andrew Good 
Jet Propulsion Laboratory, Pasadena, Calif. 
818-393-2433 
andrew.c.good@jpl.nasa.gov 

Karen Fox / Molly Wasser 
NASA Headquarters, Washington
202-358-1600
karen.c.fox@nasa.gov / molly.l.wasser@nasa.gov

2025-140

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Dec 16, 2025

NASA, Partners Share First Data From New US-European Sea Satellite

✇NASA Breaking News
By: scarney1

5 min read

Preparations for Next Moonwalk Simulations Underway (and Underwater)

A map showing a portion of the North Atlantic Ocean, with the U.S. Eastern seaboard along the left side of the frame, is covered with wide yellow lines criss-crossing in X shapes. Written on the lines in black ink is either “S6MF” for Sentinel-6 Michael Freilich or “S6B” for Sentinel-6B, showing the orbital paths of each satellite. On the left side of the image, a legend labeled “sea level anomaly (cm)” shows a vertical, rainbow-hued graph ranging from dark blue at the bottom to dark red at the top; the colors correspond to blobs of each shade that cover the ocean on the map.
Sentinel-6B and Sentinel-6 Michael Freilich captured data on Nov. 26 of sea levels across a vast stretch of the Atlantic. Within the crisscrossing bands, red indicates higher water relative to the long-term average; blue indicates lower water. The tracks are layered atop the combined observations of other sea-level satellites.
EUMETSAT

Launched in November, Sentinel-6B will track ocean height with ultraprecision to advance marine forecasting, national security, and more.

Sentinel-6B, a joint mission by NASA and its U.S. and European partners to survey 90% of the world’s oceans for the benefit of communities and commerce, has started sending back its first measurements since launching in November. A newly published map of the data shows sea levels across a vast stretch of the Eastern Seaboard and Atlantic Ocean. 

About the size of a pickup truck, Sentinel-6B extends a decades-long effort led by the United States and Europe to track ocean height down to fractions of an inch using radar altimetry. Once its instruments and algorithms are fully calibrated next year, Sentinel-6B will return actionable data for ship crews, weather forecasters, national security, and the millions of people who live and work near coastlines.  

“NASA does incredible science using the unique vantage point of space every day to deliver life-saving data directly into the hands of decision-makers for storms, navigation, flooding, and more,” said Nicky Fox, associate administrator, Science Mission Directorate, NASA Headquarters in Washington. “The ocean measurements that Sentinel-6B collected during its first months in orbit benefit all, providing key insights to ensure the prosperity and security of coastal communities around the globe.” 

In addition to measuring sea level, instruments aboard the satellite will gather information on wind speeds, wave heights, atmospheric temperature, and humidity. In turn, that data can be used by U.S. agencies as well as to refine the Goddard Earth Observing System atmospheric forecast models, which the NASA Engineering and Safety Center relies on to plan safer re-entry of astronauts returning from Artemis missions.  

Mission teams in recent weeks have verified that Sentinel-6B and all its instruments are in good health. That includes the Poseidon-4 Synthetic Aperture Radar altimeter, the Advanced Microwave Radiometer for Climate, the Global Navigation Satellite System – Radio Occultation, and the Precise Orbit Determination Package. 

In the visualization above, featuring data captured by Sentinel-6B on Nov. 26, the crisscrossing bands trace the satellite’s path as it orbits Earth. The image also shows data collected on the same day by the satellite’s twin, Sentinel-6 Michael Freilich, which launched in 2020. The data in those bands is layered over the combined observations of other sea-level satellites across the region shown. Red indicates higher water relative to the long-term average; blue areas indicate lower water. Because the spacecraft’s instruments have not been fully calibrated, the data is considered preliminary but also quite promising. 

Together, Sentinel-6B and Sentinel-6 Michael Freilich make up the Copernicus Sentinel-6/Jason-CS (Continuity of Service) mission developed by NASA, ESA (European Space Agency), EUMETSAT (European Organisation for the Exploitation of Meteorological Satellites), and the National Oceanic and Atmospheric Administration (NOAA). 

“These first light images from Sentinel-6B underscore the value of Earth science observations in providing life-saving and economic-empowering data to communities along our world’s coastlines, where a third of the globe’s population lives,” said Karen St. Germain, director, NASA Earth Science Division at the agency’s headquarters. “This achievement also highlights the power of partnerships with ESA, EUMETSAT, and our sister science agency NOAA in advancing our collective understanding of Earth systems and putting that Earth science understanding to work for the benefit of humanity.” 

Sentinel-6/Jason-CS adds to a continuous sea level rise dataset that began in the early 1990s. Since then, the rate of sea level rise globally has doubled and currently averages about 0.17 inches (4.3 millimeters) per year. The rate differs between locations, with implications for coastal infrastructure, trade routes, and storm formation. 

“The accuracy and precision of this mission’s gold-standard dataset speaks to the foresight, more than 30 years ago, of investing in the technology and expertise that make it possible,” said Dave Gallagher, director, NASA’s Jet Propulsion Laboratory in Southern California. “We’re proud to continue partnering to collect these critical measurements into another decade, and even prouder of the teams behind this most recent milestone.” 

Flying 830 miles (1,336 kilometers) above Earth, Sentinel-6B is about 30 seconds behind its twin, Sentinel-6 Michael Freilich, currently the official reference satellite for sea level. Eventually, Sentinel-6B will take over that role, and Sentinel-6 Michael Freilich will move into a different orbit.

More about Sentinel-6B 

Copernicus Sentinel-6/Jason-CS was jointly developed by ESA, EUMETSAT, NASA, and NOAA, with funding support from the European Commission and technical support from CNES. The mission, starting with Sentinel-6 Michael Freilich, marked the first international involvement in Copernicus, the European Union’s Earth Observation Programme. 

Managed for NASA by Caltech in Pasadena, JPL contributed three science instruments for each Sentinel-6 satellite: the Advanced Microwave Radiometer, the Global Navigation Satellite System – Radio Occultation, and the laser retroreflector array. NASA also contributed launch services, ground systems supporting operation of the NASA science instruments, the science data processors for two of these instruments, and support for the international ocean surface topography community. 

For more about Sentinel-6B, visit: 

https://science.nasa.gov/mission/sentinel-6B/

News Media Contacts

Elizabeth Vlock
NASA Headquarters, Washington
202-358-1600
elizabeth.a.vlock@nasa.gov

Andrew Wang / Andrew Good
Jet Propulsion Laboratory, Pasadena, Calif.
626-379-6874 / 626-840-4291
andrew.wang@jpl.nasa.gov / andrew.c.good@jpl.nasa.gov

2025-139

NASA JPL Unveils Rover Operations Center for Moon, Mars Missions

✇NASA Breaking News
By: scarney1

5 min read

Preparations for Next Moonwalk Simulations Underway (and Underwater)

This video highlights the Rover Operations Center at NASA’s Jet Propulsion Laboratory. A center of excellence for current and future rover, aerial, and other surface missions, the ROC will support partnerships and technology transfer to catalyze the next generation of Moon and Mars surface missions. Credit: NASA/JPL-Caltech

The center leverages AI along with JPL’s unique infrastructure, unrivaled tools, and years of operations expertise to support industry partners developing future planetary surface missions.  

NASA’s Jet Propulsion Laboratory in Southern California on Wednesday inaugurated its Rover Operations Center (ROC), a center of excellence for current and future surface missions to the Moon and Mars. During the launch event, leaders from the commercial space and AI industries toured the facilities, participated in working sessions with JPL mission teams, and learned more about the first-ever use of generative AI by NASA’s Perseverance Mars rover team to create future routes for the robotic explorer. 

The center was established to integrate and innovate across JPL’s planetary surface missions while simultaneously forging strategic partnerships with industry and academia to advance U.S. interests in the burgeoning space economy. The center builds on JPL’s 30-plus years of experience developing and operating Mars surface missions, including humanity’s only helicopter to fly at Mars as well as the only two active planetary surface missions. 

“The Rover Operations Center is a force multiplier,” said JPL Director Dave Gallagher. “It integrates decades of specialized knowledge with powerful new tools, and exports that knowledge through partnerships to catalyze the next generation of Moon and Mars surface missions. As NASA’s federally funded research and development center, we are chartered to do exactly this type of work — to increase the cadence, the efficiency, and the impact for our transformative NASA missions and to support the commercial space market as they take their own giant leaps.” 

A rover drives down an incline as a group of people watch from a distance.
Rover prototype ERNEST (Exploration Rover for Navigating Extreme Sloped Terrain) demonstrates some of its advanced mobility and autonomy capabilities in JPL’s Mars Yard.
NASA/JPL-Caltech

Genesis of ROC 

Through decades of successful Mars rover missions, JPL has continuously improved the unique autonomy, robotic capabilities, and best practices that have been demanded by increasingly complex robotic explorers. The ROC offers an accessible centralized structure to facilitate future exploration efforts. 

“Our rovers are lasting longer and are more sophisticated than ever before. The scientific stakes are high, as we have just witnessed with the discovery of a potential biosignature in Jezero Crater by the Perseverance mission. We are starting down a decade of unprecedented civil and commercial exploration at the Moon, which will require robotic systems to assist astronauts and support lunar infrastructure,” said Matt Wallace, who heads JPL’s Exploration Systems Office. “Mobile vehicles like rovers, helicopters, and drones are the most dynamic and challenging assets we operate. It’s time to take our game up a notch and bring everybody we can with us.”  

A man, illuminated by white light, talking to a group of people in a room that is otherwise dark and dimly lit with blue light.
Michael Thelen of JPL’s Exploration Systems Office discusses the newly inaugurated Rover Operations Center in JPL’s historic Space Flight Operations Facility on Dec. 10.
NASA/JPL-Caltech

Future forward  

A key focus of the ROC is on the more rapid infusion of higher-level autonomy into surface missions through partnerships with the AI and commercial space industries. The objective is to catalyze change to deliver next-generation science and exploration capabilities for the nation and NASA. 

As NASA’s only federally funded research and development center, JPL has been evolving vehicle autonomy since the 1990s, when JPL began developing Sojourner, the first rover on another planet. Improvements to vehicle independence over the years have included the evolution of autonomy in sampling activities, driving, and science-target selection. Most recently, those improvements have extended to the development of Perseverance’s ability to autonomously schedule and execute many commanded energy-intensive activities, like keeping warm at night, as it sees fit. This capability allows the rover to conserve power, which it can reallocate in real time to perform more science or longer drives. 

With the explosion of AI capabilities, the ROC rover team is leaving no Mars stone unturned in the hunt for future efficiencies.  

“We had a small team complete a ‘three-week challenge,’ applying generative AI to a few of our operational use cases. During this challenge, it became clear there are many opportunities for AI infusion that can supercharge our capabilities,” said Jennifer Trosper, ROC program manager at JPL. “With these new partnerships, together we will infuse AI into operations to path-find the next generation of capabilities for science and exploration.”  

Håvard Grip, chief pilot of NASA’s Mars Ingenuity Helicopter — the only aircraft to fly on another planet — offers insights into aerial exploration of the Red Planet at the lab’s 25-Foot Space Simulator, which subjects spacecraft to the harsh conditions of space.

During the ROC’s inauguration, attendees toured JPL operations facilities, including where the rover drivers plan their next routes. They also visited JPL’s historic Mars Yard, which reproduces Martian terrain to test rover capabilities, and the massive 25-Foot Space Simulator that has tested spacecraft from Voyagers 1 and 2 to Perseverance to America’s next generation of lunar landers. A panel discussion explored the historical value of rovers and aerial systems like the Ingenuity Mars Helicopter in planetary surface exploration. Also discussed was the promise of a new public-private partnership opportunity across a virtual network of operational missions.  

Attendees were briefed on tiered engagement options for partners, from mission architecture support to autonomy integration, testing, and operations. These opportunities extend to science and human precursor robotic missions, as well as to human-robotic interaction and spacewalks for astronauts on the Moon and Mars. 

A highlight for event participants came when the Perseverance team showcased how the ROC’s generative AI can assist rover planners in creating future routes for the rover. The AI analyzed high-resolution orbital images of Jezero Crater and other relevant data and then generated waypoints that kept Perseverance away from hazardous terrain. 

Managed for NASA by Caltech, JPL is the home of the Rover Operations Center (ROC).  

To learn more about the ROC, visit:

https://www.jpl.nasa.gov/roc

News Media Contact

DC Agle
Jet Propulsion Laboratory, Pasadena, Calif.
818-393-9011
agle@jpl.nasa.gov

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Meet the ROC. A center of excellence for current and future rover, aerial, and other surface missions, the Rover Operations Center at NASA’s Jet Propulsion L...

NASA Orbiter Shines New Light on Long-Running Martian Mystery

✇NASA Breaking News
By: scarney1

5 min read

Preparations for Next Moonwalk Simulations Underway (and Underwater)

The European Space Agency’s Mars Express orbiter captured this view of Mars’ south polar ice cap Feb. 25, 2015. Three years later, the spacecraft detected a signal from the area to the right of the ice cap that scientists interpreted as an underground lake.
The European Space Agency’s Mars Express orbiter captured this view of Mars’ south polar ice cap Feb. 25, 2015. Three years later, the spacecraft detected a signal from the area to the right of the ice cap that scientists interpreted as an underground lake.
ESA/DLR/FU Berlin, CC BY-SA 3.0 IGO

Results from an enhanced radar technique have demonstrated improvement to sub-surface observations of Mars. 

NASA’s Mars Reconnaissance Orbiter (MRO) has revisited and raised new questions about a mysterious feature buried beneath thousands of feet of ice at the Red Planet’s south pole. In a recent study, researchers conclude from data obtained using an innovative radar technique that an area on Mars suspected of being an underground lake is more likely to be a layer of rock and dust.  

The 2018 discovery of the suspected lake set off a flurry of scientific activity, as water is closely linked with life in the solar system. While the latest findings indicate this feature is not a lake below the Martian surface, it does suggest that the same radar technique could be used to check for subsurface resources elsewhere on Mars, supporting future explorers. 

The paper, published in Geophysical Research Letters on Nov. 17, was led by two of MRO’s Shallow Radar (SHARAD) instrument scientists, Gareth Morgan and Than Putzig, who are based at the Planetary Science Institute in Tucson, Arizona, and Lakewood, Colorado, respectively. 

The observations were made by MRO with a special maneuver that rolls the spacecraft 120 degrees. Doing so enhances the power of SHARAD, enabling the radar’s signal to penetrate deeper underground and provide a clearer image of the subsurface. These “very large rolls” have proved so effective that scientists are eager to use them at previously observed sites where buried ice might exist. 

This map shows the approximate area where in 2018 ESA’s Mars Express detected a signal the mission’s scientists interpreted as an underground lake. The red lines show the path of NASA’s Mars Reconnaissance Orbiter, which flew both directly overhead as well as over an adjacent region. Credit: Planetary Science Institute
This map shows the approximate area where in 2018 ESA’s Mars Express detected a signal the mission’s scientists interpreted as an underground lake. The red lines show the path of NASA’s Mars Reconnaissance Orbiter, which flew both directly overhead as well as over an adjacent region. Credit: Planetary Science Institute

Morgan, Putzig, and fellow SHARAD team members had made multiple unsuccessful attempts to observe the area suspected of hosting a buried lake. Then the scientists partnered with the spacecraft’s operations team at NASA’s Jet Propulsion Laboratory in Southern California, which leads the mission, to develop the very large roll capability. 

Because the radar’s antenna is at the back of MRO, the orbiter’s body obstructs its view and weakens the instrument’s sensitivity. After considerable work, engineers at JPL and Lockheed Martin Space in Littleton, Colorado, which built the spacecraft and supports its operations, developed commands for a 120-degree roll — a technique that requires careful planning to keep the spacecraft safe — to direct more of SHARAD’s signal at the surface.

Bright signal  

On May 26, SHARAD performed a very large roll to finally pick up the signal in the target area, which spans about 12.5 miles (20 kilometers) and is buried under a slab of water ice almost 1 mile (1,500 meters) thick.  

When a radar signal bounces off underground layers, the strength of its reflection depends on what the subsurface is made of. Most materials let the signal slip through or absorb it, making the return faint. Liquid water is special in that it produces a very reflective surface, sending back a very strong signal (imagine pointing a flashlight at a mirror). 

That’s the kind of signal that was spotted from this area in 2018 by a team working with the Mars Advanced Radar for Subsurface and Ionospheric Sounding (MARSIS) instrument aboard the ESA (European Space Agency) Mars Express orbiter. To explain how such a body of water could remain liquid under all that ice, scientists have hypothesized it could be a briny lake, since high salt content can lower water’s freezing temperature. 

An antenna sticks out like whiskers from NASA’s Mars Reconnaissance Orbiter in this artist’s concept depicting the spacecraft, which has been orbiting the Red Planet since 2006. This antenna is part of SHARAD, a radar that peers below the Martian surface.
NASA/JPL-Caltech

“We’ve been observing this area with SHARAD for almost 20 years without seeing anything from those depths,” said Putzig. But once MRO achieved a very large roll over the precise area, the team was able to look much deeper. And rather than the bright signal MARSIS received, SHARAD detected a faint one. A different very-large-roll observation of an adjacent area didn’t detect a signal at all, suggesting something unique is causing a quirky radar signal at the exact spot MARSIS saw a signal. 

“The lake hypothesis generated lots of creative work, which is exactly what exciting scientific discoveries are supposed to do,” said Morgan. “And while this new data won’t settle the debate, it makes it very hard to support the idea of a liquid water lake.”

Alternative explanations

Mars’ south pole has an ice cap sitting atop heavily cratered terrain, and most radar images of the area below the ice show lots of peaks and valleys. Morgan and Putzig said it’s possible that the bright signal MARSIS detected here may just be a rare smooth area — an ancient lava flow, for example. 

Both scientists are excited to use the very large roll technique to reexamine other scientifically interesting regions of Mars. One such place is Medusae Fossae, a sprawling geologic formation on Mars’ equator that produces little radar return. While some scientists have suggested it’s composed of layers of volcanic ash, others have suggested the layers may include heaps of ice deep within. 

“If it’s ice, that means there’s lots of water resources near the Martian equator, where you’d want to send humans,” said Putzig. “Because the equator is exposed to more sunlight, it’s warmer and ideal for astronauts to live and work.” 

More about MRO

NASA’s Jet Propulsion Laboratory in Southern California manages MRO for the agency’s Science Mission Directorate in Washington as part of NASA’s Mars Exploration Program portfolio. Lockheed Martin Space in Denver built MRO and supports its operations. SHARAD was provided to the MRO mission by the Italian Space Agency (ASI).

News Media Contacts

Andrew Good 
Jet Propulsion Laboratory, Pasadena, Calif. 
818-393-2433 
andrew.c.good@jpl.nasa.gov 

Karen Fox / Molly Wasser 
NASA Headquarters, Washington
202-358-1600
karen.c.fox@nasa.gov / molly.l.wasser@nasa.gov

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NASA, Aerospace Corporation Study Sharpens Focus on Ammonia Emissions

✇NASA Breaking News
By: scarney1

6 min read

Preparations for Next Moonwalk Simulations Underway (and Underwater)

Researchers used data taken in March 2023 by an airborne imaging spectrometer to map ammonia emissions in the Imperial Valley. Produced by agricultural activities as well as geothermal processes, ammonia is a precursor to particulate matter, which can cause adverse health outcomes when inhaled.
NASA/JPL-Caltech

The pungent gas contributes to fine airborne particulate pollution, which endangers human health when inhaled and absorbed in the bloodstream. 

A recent study led by scientists at NASA’s Jet Propulsion Laboratory in Southern California and the nonprofit Aerospace Corporation shows how high-resolution maps of ground-level ammonia plumes can be generated with airborne sensors, highlighting a way to better track the gas. A key chemical ingredient of fine particulate matter — tiny particles in the air known to be harmful when inhaled — ammonia can be released through agricultural activities such as livestock farming and geothermal power generation as well as natural geothermal processes. Because it’s not systematically monitored, many sources of the pungent gas go undetected.  

Published in Atmospheric Chemistry and Physics in October, the study focuses on a series of 2023 research flights that covered the Imperial Valley to the southeast of the Salton Sea in inland Southern California, as well as the Eastern Coachella Valley to its northwest. Prior satellite-based research has identified the Imperial Valley as a prolific source of gaseous ammonia. In the study, scientists employed an airborne sensor capable of resolving ammonia plumes with enough detail to track their origins: Aerospace Corporation’s Mako instrument is an imaging spectrometer that observes long-wave infrared light emitted by areas of Earth’s surface and atmosphere 6 feet (2 meters) across. 

Using the instrument, which can detect ammonia’s chemical signature by the infrared light it absorbs, the authors found elevated levels of the gas near several sources, including agricultural fields, livestock feedlots, geothermal plants, and geothermal vents. Measurements in parts of the Imperial Valley were 2½ to eight times higher than in Coachella Valley’s Mecca community, which had ammonia concentrations closer to background levels. 

Though not toxic on its own in low concentrations, ammonia is a precursor to particulate matter, also known as aerosol or particle pollution. It reacts with other gases to form solid ammonium salt particles small enough to penetrate the bloodstream from the lungs. Particles under 2.5 micrometers in diameter — also known as PM2.5 — are associated with elevated rates of asthma, lung cancer, and cardiovascular disease, among other negative health outcomes. 

“Historically, more attention has focused on primary sources of PM2.5, such as auto emissions. But with significant reductions in those emissions and increasingly stringent air quality standards, there is growing interest in understanding secondary sources that form particles in the air from precursor gases,” said Sina Hasheminassab, lead author of the paper and a research scientist at JPL. “As an important precursor to PM2.5, ammonia plays a key role, but its emissions are poorly characterized and undermonitored.” 

Rising ammonia 

Previous satellite-based studies have shown rising levels of atmospheric ammonia, both globally and in the continental United States. That research revealed broad trends, but with spatial resolution on the order of tens of miles, the measurements were only sufficient to identify variation over areas of hundreds of square miles or more. 

The chemical behavior of ammonia also poses a particular monitoring challenge: Once emitted, it only stays in the atmosphere for hours before reacting with other compounds. In contrast, carbon dioxide can remain in the air for centuries. 

Planes and satellites can provide an overview of sources and the geographic distribution of emissions at a given moment. Although satellites offer wider and more recurrent coverage, airborne instruments, being closer to the source, produce higher-resolution data and can focus on specific locations at designated times.  

Those proved to be the right capabilities for the recent study. Researchers flew Mako over the Imperial and Eastern Coachella valleys on the mornings and afternoons of March 28 and Sept. 25, 2023, and took concurrent measurements on the ground with both a fixed monitoring station in Mecca operated by the South Coast Air Quality Management District (AQMD) and a mobile spectrometer developed at the University of California, Riverside. 

“The goal was to show that this technique was capable of delivering data with the required accuracy that aerosol scientists and potentially even air quality regulatory bodies could use to improve the air quality in those regions,” said David Tratt, a senior scientist at Aerospace Corporation and coauthor of the paper. “We ended up with maps that identify multiple sources of ammonia, and we were able to track the plumes from their sources and observe them coalescing into larger clouds.” 

Distinct plumes 

During the flights, the team collected data over the southeastern coast of the Salton Sea, which straddles Riverside and Imperial counties. There, Mako revealed small plumes coming from geothermal fumaroles venting superheated water and steam that react with nitrogen-bearing compounds in the soil, releasing ammonia. 

Farther to the southeast, the results showed several geothermal power plants emitting ammonia, primarily from their cooling towers, as part of their normal operations. 

Farther southeast still, the researchers spotted ammonia emissions, a byproduct of animal waste, from cattle farms in the Imperial Valley. During the March 28 flight, a plume from the largest facility in the study area measured up to 1.7 miles (2.8 kilometers) wide and extended up to 4.8 miles (7.7 kilometers) downwind of the source.

‘Very large puzzle’ 

As part of the study, AQMD’s Mecca monitoring station recorded seasonal changes in ammonia concentrations. Given the few sources in the area, the researchers surmised that winds during certain months tend to blow the gas from Imperial Valley to the Coachella Valley. 

The study underscores the benefits of detailed spatial information about ammonia emissions, and it partly informed the agency’s decision in July to expand its ammonia-monitoring network and extend the life of the Mecca station. 

As a precursor to PM2.5, ammonia is “one piece of a very large puzzle” that, for Coachella Valley residents, includes vehicle emissions, desert dust, and agricultural activities, said Payam Pakbin, manager of the Advanced Monitoring Technologies Unit at AQMD and a paper coauthor. 

“These communities want to know the contributions of these sources to the air quality they’re experiencing,” he added. “Findings like these help our agency better prioritize which sources require the most attention and ultimately guide our focus toward those that are the highest priority for achieving emission reductions in this community.” 

News Media Contacts

Andrew Wang / Andrew Good
Jet Propulsion Laboratory, Pasadena, Calif.
626-379-6874 / 626-840-4291
andrew.wang@jpl.nasa.gov / andrew.c.good@jpl.nasa.gov

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Nov 20, 2025

NASA’s Mars Spacecraft Capture Images of Comet 3I/ATLAS

✇NASA Breaking News
By: scarney1

6 min read

Preparations for Next Moonwalk Simulations Underway (and Underwater)

On a largely black background, interstellar comet 3I/ATLAS appears as a white smudge with a semicircular shape at its core. A transparent white cloud extends slightly from the comet toward the bottom left of the image and, to a lesser extent, toward the right side of the image.
The High-Resolution Imaging Science Experiment (HiRISE) camera aboard NASA’s Mars Reconnaissance Orbiter captured this image of interstellar comet 3I/ATLAS on Oct. 2, 2025. At the time it was imaged, the comet was about 0.2 astronomical units (18.6 million miles, or 29.9 million kilometers) from the from the spacecraft.
NASA/JPL-Caltech/University of ArizonaNASA/JPL-Caltech/University of Arizona
On a largely black background, interstellar comet 3I/ATLAS appears as a white smudge with a semicircular shape at its core. A transparent white cloud extends slightly from the comet toward the bottom left of the image and, to a lesser extent, toward the right side of the image. A scale bar indicates a distance of 932 miles above the comet, and an arrow pointing from the comet to the bottom left of the image is labeled “comet trajectory.”
An annotated version of the image of 3I/ATLAS captured by NASA’s Mars Reconnaissance Orbiter shows the trajectory of the interstellar comet along with a scale bar. The image was captured by the spacecraft’s High Resolution Imaging Science Experiment (HiRISE) camera on Oct. 2, 2025.
NASA/JPL-Caltech/University of Arizona

Two orbiters and a rover captured images of the interstellar object — from the closest location any of the agency’s spacecraft may get — that could reveal new details.

At the start of October, three of NASA’s Mars spacecraft had front row seats to view 3I/ATLAS, only the third interstellar object so far discovered in our solar system. The Mars Reconnaissance Orbiter (MRO) snapped a close-up of the comet, while the MAVEN (Mars Atmosphere and Volatile EvolutioN) orbiter captured ultraviolet images and the Perseverance rover caught a faint glimpse as well.  

Imagery from MRO will allow scientists to better estimate the comet’s size, and MAVEN’s images are unique among all observations this year in determining the chemical makeup of the comet and how much water vapor is released as the Sun warms the comet. These details will help scientists better understand the past, present, and future of this object.

HiRISE 

The comet will be at its closest approach to Earth on Friday, Dec. 19. On Oct. 2, MRO observed 3I/ATLAS from 19 million miles (30 million kilometers) away, with one of the closest views that any NASA spacecraft or Earth-based telescopes are expected to get.  

The orbiter’s team viewed the comet with a camera called HiRISE (the High Resolution Imaging Science Experiment), which normally points at the Martian surface. By rotating, MRO can point HiRISE at celestial objects as well — a technique used in 2014, when HiRISE joined MAVEN in studying another comet, called Siding Spring. 

Captured at a scale of roughly 19 miles (30 kilometers) per pixel, 3I/ATLAS looks like a pixelated white ball on the HiRISE imagery. That ball is a cloud of dust and ice called the coma, which the comet shed as it continued its trajectory past Mars. 

A square, pixelated image with a dark background. At the center is a roughly circular cluster of bright pixels, transitioning from white at the very center to light blue, then darker blue and purple as it spreads outward. The edges and corners of the image are mostly dark purple and black pixels.
This ultraviolet image shows the halo of gas and dust, or coma, surrounding comet 3I/ATLAS as seen on Oct. 9, 2025, by NASA’s MAVEN spacecraft using its Imaging Ultraviolet Spectrograph. The brightest pixel at center indicates where the comet is. The surrounding bright pixels show where hydrogen atoms were detected coming from the comet.
NASA/Goddard/LASP/CU Boulder
A wide, rectangular, pixelated image with a dark purple background. Near the right side, there is a bright, elongated cluster of pixels labeled “Mars hydrogen” that transition from white at the center to light blue and then darker blue as they extend leftward. Fainter blue and purple pixels form a tapered shape stretching further to the left, labeled “interplanetary hydrogen”. Farther left is a more circular cluster of faint blue pixels, labeled “Comet 3I/ATLAS hydrogen.” The rest of the image is filled with dark purple and black pixels.
This annotated composite image showing hydrogen atoms from three sources, including 3I/ATLAS (at left), was captured Sept. 28, 2025, by NASA’s MAVEN orbiter using its Imaging Ultraviolet Spectrograph. Hydrogen emitted by Mars is the bright streak at right, with interplanetary hydrogen flowing through the solar system indicated by the dimmer streak in the middle.
NASA/Goddard/LASP/CU Boulder

“Observations of interstellar objects are still rare enough that we learn something new on every occasion,” said Shane Byrne, HiRISE principal investigator at the University of Arizona in Tucson. “We’re fortunate that 3I/ATLAS passed this close to Mars.” 

Further study of the HiRISE imagery could help scientists estimate the size of the comet’s nucleus, its central core of ice and dust. More study also may reveal the size and color of particles within its coma. 

“One of MRO’s biggest contributions to NASA’s work on Mars has been watching surface phenomena that only HiRISE can see,” said MRO’s project scientist Leslie Tamppari of NASA’s Jet Propulsion Laboratory in Southern California. “This is one of those occasions where we get to study a passing space object as well.” 

MAVEN  

Over the course of 10 days starting Sept. 27, MAVEN captured 3I/ATLAS in two unique ways with its Imaging Ultraviolet Spectrograph (IUVS) camera. First, IUVS took multiple images of the comet in several wavelengths, much like using various filters on a camera. Then it snapped high-resolution UV images to identify the hydrogen coming from 3I/ATLAS. Studying a combination of these images, scientists can identify a variety of molecules and better understand the comet’s composition.  

“The images MAVEN captured truly are incredible,” said Shannon Curry, MAVEN’s principal investigator and research scientist at the Laboratory for Atmospheric and Space Physics (LASP) at the University of Colorado Boulder. “The detections we are seeing are significant, and we have only scraped the surface of our analysis.” 

The IUVS data also offers an estimated upper limit of the comet’s ratio of deuterium (a heavy isotope of hydrogen) to regular hydrogen, a tracer of the comet’s origin and evolution. When the comet was at its closest to Mars, the team used more sensitive channels of IUVS to map different atoms and molecules in the comet’s coma, such as hydrogen and hydroxyl. Further study of the comet’s chemical makeup could reveal more about its origins and evolution. 

“There was a lot of adrenaline when we saw what we’d captured,” said MAVEN’s deputy principal investigator, Justin Deighan, a LASP scientist and the lead on the mission’s comet 3I/ATLAS observations. “Every measurement we make of this comet helps to open up a new understanding of interstellar objects.” 

A predominantly black view of space is dotted with stars, seen as short white streaks, in an animated image that consists of two observations. In the right half of the image, interstellar comet 3I/ATLAS is a barely visible white smudge that becomes slightly more distinct in the second observation.
Interstellar comet 3I/ATLAS is seen as a faint smudge against a background starfield in two images taken by the Mastcam-Z instrument aboard NASA’s Perseverance Mars rover on Oct. 4, 2025. At the time it was imaged, the comet was about 19 million miles (30 million kilometers) from the rover, which was exploring the rim of the Red Planet’s Jezero Crater.
NASA/JPL-Caltech/ASU/MSSS

Perseverance 

Far below the orbiters, on the Martian surface, NASA’s Perseverance rover also caught sight of 3I/ATLAS. On Oct. 4, the comet appeared as a faint smudge to the rover’s Mastcam-Z camera. The exposure had to be exceptionally long to detect such a faint object. Unlike telescopes that track objects as they move, Mastcam-Z is fixed in place during long exposures. This technique produces star trails that appear as streaks in the sky, though the comet itself is barely perceptible. 

More about MRO, MAVEN, Perseverance 

A division of Caltech in Pasadena, California, JPL manages MRO for NASA’s Science Mission Directorate in Washington as part of NASA’s Mars Exploration Program portfolio. The University of Arizona in Tucson operates MRO’s HiRISE, which was built by BAE Systems in Boulder, Colorado. Lockheed Martin Space in Denver built MRO and supports its operations. 

The MAVEN mission, also part of NASA’s Mars Exploration Program portfolio, is led by the Laboratory for Atmospheric and Space Physics at the University of Colorado Boulder. It’s managed by NASA’s Goddard Space Flight Center in Greenbelt, Maryland. MAVEN was built and operated by Lockheed Martin Space in Littleton, Colorado, with navigation and network support from JPL. 

JPL built and manages operations of the Perseverance rover on behalf of the agency’s Science Mission Directorate as part of NASA’s Mars Exploration Program portfolio. 

To learn more about NASA’s observations of comet 3I/ATLAS, visit: 

https://go.nasa.gov/3I-ATLAS

News Media Contacts

Andrew Good 
Jet Propulsion Laboratory, Pasadena, Calif. 
818-393-2433 
andrew.c.good@jpl.nasa.gov 

Alise Fisher / Molly Wasser 
NASA Headquarters, Washington 
202-617-4977 / 240-419-1732 
alise.m.fisher@nasa.gov / molly.l.wasser@nasa.gov 

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NASA, European Partners Set to Launch Sentinel-6B Earth Satellite

✇NASA Breaking News
By: scarney1

5 min read

Preparations for Next Moonwalk Simulations Underway (and Underwater)

A wide-angle, distant photo of a white rocket on the launch pad, brightly lit, with a black night sky behind it.
Set to launch no earlier than Nov. 16, Sentinel-6B will continue the data record now being collected by its twin satellite Sentinel-6 Michael Freilich, which lifted off from Vandenberg Space Force Base in November 2020 aboard the SpaceX Falcon 9 rocket shown here.
SpaceX

Set to track sea levels across more than 90% of Earth’s ocean, the mission must first get into orbit. Here’s what to expect.  

Sentinel-6B, an ocean-tracking satellite jointly developed by NASA and ESA (European Space Agency), is ready to roll out to the launch pad, packed into the payload fairing of a SpaceX Falcon 9 rocket.   

Launch is targeted at 12:21 a.m. EST, Monday, Nov. 17 (9:21 p.m. PST, Sunday, Nov. 16). Once it lifts off from Vandenberg Space Force Base in California, the satellite will ride out a 57-minute sequence of events ending in spacecraft separation, when the satellite detaches from the rocket.  

Then Sentinel-6B’s real work begins. Orbiting Earth every 112 minutes at 4.5 miles (7.2 kilometers) per second, the satellite will eventually take over for its twin, Sentinel-6 Michael Freilich, launched five years ago, to continue a multidecade dataset for sea level measurements from space. Those measurements, along with atmospheric data the mission gathers, will help improve public safety and city planning while protecting coastal infrastructure, including power plants and defense interests. NASA will also use the data to refine atmospheric models that support the safe re-entry of Artemis astronauts.  

Here’s a closer look at what lies ahead for the satellite in the coming days.

Launch timeline 

Measuring 19.1 feet (5.82 meters) long and 7.74 feet (2.36 meters) high (including the communications antennas), the satellite weighs in at around 2,600 pounds (1,200 kilograms) when loaded with propellant at launch. 

The satellite will lift off from Space Launch Complex 4 East at Vandenberg. If needed, backup launch opportunities are available on subsequent days, with the 20-second launch window occurring about 12 to 13 minutes earlier each day.  

A little more than two minutes after the Falcon 9 rocket lifts off, the main engine cuts off. Shortly after, the rocket’s first and second stages separate, followed by second-stage engine start. The reusable Falcon 9 first stage then begins its automated boost-back burn to the launch site for a powered landing. About three minutes after launch, the two halves of the payload fairing, which protected the satellite as it traveled through the atmosphere, separate and fall safely back to Earth.  

The first cutoff of the second stage engine takes place approximately eight minutes after liftoff, at which point the launch vehicle and the spacecraft will be in a temporary “parking” orbit. The second stage engine fires a second time about 44 minutes later, and about 57 minutes after liftoff, the rocket and the spacecraft separate. Roughly seven minutes after that, the satellite’s solar panels deploy. Sentinel-6B is expected to make first contact with ground controllers about 35 minutes after separation (roughly an hour and a half after liftoff) — a major milestone indicating that the spacecraft is healthy. 

Science mission 

Following launch operations, the team will focus on its next challenge: getting the spacecraft ready for science operations. Once in orbit, Sentinel-6B will fly about 30 seconds behind its twin, the Sentinel-6 Michael Freilich satellite. When scientists and engineers have completed cross-calibrating the data collected by the two spacecraft, Sentinel-6B will take over the role of providing primary sea level measurements while Sentinel-6 Michael Freilich will move into a different orbit. From there, researchers plan to use measurements from Sentinel-6 Michael Freilich for different purposes, including helping to map seafloor features (variations in sea surface height can reveal variations in ocean floor features, such as seamounts). 

Sentinel-6B is part of a U.S.-European mission that will continue 30-year-plus record of sea-level measurements. Its observations will help build an accurate picture of local and global sea surface heights to support storm forecasting, secure coastal infrastructure, and help optimize commercial activities, such as shipping.
NASA/JPL-Caltech

Where to find launch coverage 

Launch day coverage of the mission will be available on the agency’s website, including links to live streaming and blog updates beginning no earlier than 11 p.m. EST, Nov. 16, as the countdown milestones occur. Streaming video and photos of the launch will be accessible on demand shortly after liftoff. Follow countdown coverage on NASA’s Sentinel-6B blog.  

For more information about NASA’s live programming schedule, visit 
plus.nasa.gov/scheduled-events. 

More about Sentinel-6B

The Copernicus Sentinel-6/Jason-CS (Continuity of Service) mission is a collaboration between NASA, ESA, EUMETSAT (European Organisation for the Exploitation of Meteorological Satellites), and the National Oceanic and Atmospheric Administration (NOAA). The European Commission contributed funding support while France’s space agency CNES (Centre National d’Études Spatiales) provided technical expertise. The mission also marks the first international involvement in Copernicus, the European Union’s Earth Observation Programme.  

A division of Caltech in Pasadena, JPL built three science instruments for each Sentinel-6 satellite: the Advanced Microwave Radiometer, the Global Navigation Satellite System – Radio Occultation, and the Laser Retroreflector Array. NASA is also contributing launch services, ground systems supporting operation of the NASA science instruments, the science data processors for two of these instruments, and support for the U.S. members of the international Ocean Surface Topography and Sentinel-6 science teams. The launch service is managed by NASA’s Launch Services Program, based at the agency’s Kennedy Space Center in Florida.

News Media Contacts

Elizabeth Vlock
NASA Headquarters, Washington
202-358-1600
elizabeth.a.vlock@nasa.gov

Andrew Wang / Andrew Good
Jet Propulsion Laboratory, Pasadena, Calif.
626-379-6874 / 626-840-4291
andrew.wang@jpl.nasa.gov / andrew.c.good@jpl.nasa.gov

2025-125

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NASA and its U.S. and international partners have teamed up to launch a new Earth-observing satellite called Sentinel-6B that will measure sea surface height...

6 Things to Know From NASA About New US, European Sea Satellite

✇NASA Breaking News
By: scarney1

6 min read

Preparations for Next Moonwalk Simulations Underway (and Underwater)

Set to launch no earlier than Nov. 16, Sentinel-6B will continue a decades-long data record of sea level measurement that will help decision-makers manage coastal flooding, support hurricane intensity forecasts, and assist in the return of astronauts from space.
NASA

Data from Sentinel-6B will continue a decades-long record of sea surface height, helping to improve coastal planning, protect critical infrastructure, and advance weather forecasts.

With launch set for no earlier than 12:21 a.m. EST Monday, Nov. 17, Sentinel-6B is the latest satellite in a series of spacecraft NASA and its partners have used to measure sea levels since 1992. Their data has helped meteorologists improve hurricane forecasts, managers protect infrastructure, and coastal communities plan. 

After launch, Sentinel-6B will begin the process of data cross-calibration with its predecessor, Sentinel-6 Michael Freilich, to provide essential information about Earth’s ocean. 

Sentinel-6B is the second of two satellites that constitute the Sentinel-6/Jason-CS (Continuity of Service) mission, a collaboration between NASA, ESA (European Space Agency), EUMETSAT (European Organisation for the Exploitation of Meteorological Satellites), and the National Oceanic and Atmospheric Administration (NOAA). The European Commission contributed funding support while France’s space agency CNES (Centre National d’Études Spatiales) provided technical expertise.

Here are six things to know about Sentinel-6B and the broader Copernicus Sentinel-6/Jason-CS mission: 

1. Sentinel-6B will deliver data on about 90% of Earth’s ocean, providing direct benefits to humanity.

Sentinel-6B will contribute to a multidecade dataset for sea level measurements from space. This data is key to helping improve public safety, city planning, and protecting commercial and defense interests. 

Pioneered by NASA and its partners, the dataset enables users in government, industry, and the research community to better understand how sea levels change over time. Combined with information from other NASA satellites, data from Copernicus Sentinel-6/Jason-CS is vital for tracking how heat and energy move through Earth’s seas and atmosphere, as well as for monitoring ocean features such as currents and eddies. The measurements come courtesy of a radar altimeter that measures sea levels for nearly all of Earth’s ocean, providing information on large-scale currents that can aid in commercial and naval navigation, search and rescue, and the tracking of debris and pollutants from disasters at sea.

Sentinel-6B is part of a U.S.-European mission that will continue 30-year-plus record of sea-level measurements. Its observations will help build an accurate picture of local and global sea surface heights to support storm forecasting, secure coastal infrastructure, and help optimize commercial activities, such as shipping.
Credit: NASA/JPL-Caltech

2. Data from the Copernicus Sentinel-6/Jason-CS mission helps NASA prepare for the next phase of space exploration.

The better we understand Earth, the better NASA can carry out its mission to explore the universe. Data from the Copernicus Sentinel-6/Jason-CS mission is used to refine the Goddard Earth Observing System atmospheric forecast models, which the NASA Engineering Safety Center uses to plan safer reentry of astronauts returning from Artemis missions.

Additionally, changes to Earth’s ocean, observed by satellites, can have measurable effects beyond our planet. For instance, while the Moon influences ocean tides on Earth, changes in those tides can also exert a small influence on the Moon. Data from Copernicus Sentinel-6/Jason-CS can help improve understanding of this relationship, knowledge that can contribute to future lunar exploration missions.

3. The Copernicus Sentinel-6/Jason-CS mission helps the U.S. respond to challenges by putting actionable information into the hands of decision-makers.

Data collected by the mission helps city planners, as well as local and state governments, to make informed decisions on protecting coastal infrastructure, real estate, and energy facilities. The mission’s sea level data also improves meteorologists’ weather predictions, which are critical to commercial and recreational navigation. By enhancing weather prediction models, data provided by Copernicus Sentinel-6/Jason-CS improves forecasts of hurricane development, including the likelihood of storm intensification, which can aid disaster preparedness and response.

4. Data from Sentinel-6B will support national security efforts.

The ocean and atmosphere measurements from Sentinel-6B will enable decision-makers to better protect coastal military installations from such events as nuisance flooding while aiding national defense efforts by providing crucial information about weather and ocean conditions. The satellite will do so by feeding near-real time data on Earth’s atmosphere and seas to forward-looking weather and ocean models. Since the measurements are part of a long-term dataset, they also can add historical context that puts the new data in perspective.

5. The Copernicus Sentinel-6/Jason-CS mission’s direct observation of sea levels delivers information critical to protecting coastlines, where nearly half of the world’s population lives.

Sea level rise varies from one area to another, meaning that some coastlines are more vulnerable than others to flooding, erosion, and saltwater contamination of underground freshwater supplies, the latter of which threatens farmland and drinking water. Sea level measurements from Sentinel-6 Michael Freilich, and soon, Sentinel-6B, form the basis of U.S. flood predictions for coastal infrastructure, real estate, energy storage sites, and other coastal assets. Knowing which regions are more vulnerable to these risks will enable U.S. industries and emergency managers to make better-informed decisions about transportation and commercial infrastructure, land-use planning, water management, and adaptation strategies.

6. The international collaboration behind the mission enables the pooling of capabilities, resources, and expertise.

The multidecadal dataset that this mission supports is the result of years of close work between NASA and several collaborators, including NASA, ESA, EUMETSAT, CNES, and NOAA. By pooling expertise and resources, this partnership has delivered cost-effective solutions that have made precise, high-impact data available to industry and government agencies alike.

More about Sentinel-6B

Copernicus Sentinel-6/Jason-CS was jointly developed by ESA, EUMETSAT, NASA, and NOAA, with funding support from the European Commission and technical support from CNES. The mission also marks the first international involvement in Copernicus, the European Union’s Earth Observation Programme. 

Managed for NASA by Caltech in Pasadena, JPL contributed three science instruments for each Sentinel-6 satellite: the Advanced Microwave Radiometer, the Global Navigation Satellite System – Radio Occultation, and the laser retroreflector array. NASA is also contributing launch services, ground systems supporting operation of the NASA science instruments, the science data processors for two of these instruments, and support for the international ocean surface topography community. 

For more about Sentinel-6B, visit:

https://science.nasa.gov/mission/sentinel-6B

News Media Contacts

Elizabeth Vlock
NASA Headquarters, Washington
202-358-1600
elizabeth.a.vlock@nasa.gov

Andrew Wang / Andrew Good
Jet Propulsion Laboratory, Pasadena, Calif.
626-379-6874 / 626-840-4291
andrew.wang@jpl.nasa.gov / andrew.c.good@jpl.nasa.gov

2025-124

💾

NASA and its U.S. and international partners have teamed up to launch a new Earth-observing satellite called Sentinel-6B that will measure sea surface height...
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