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Preparations for Next Moonwalk Simulations Underway (and Underwater)
NASA’s Athena Economical Payload Integration Cost mission, or Athena EPIC, is a test launch for an innovative, scalable space vehicle design to support future missions. The small satellite platform is engineered to share resources among the payloads onboard by managing routine functions so the individual payloads don’t have to.
This technology results in lower costs to taxpayers and a quicker path to launch.
“Increasing the speed of discovery is foundational to NASA. Our ability to leverage access to innovative space technologies across federal agencies through industry partners is the future,” said Clayton Turner, Associate Administrator for Space Technology Mission Directorate at NASA headquarters in Washington. “Athena EPIC is a valuable demonstration of the government at its best — serving humankind to advance knowledge with existing hardware configured to operate with new technologies.”
NOAA (National Oceanic and Atmospheric Administration) and the U.S. Space Force are government partners for this demo mission. Athena EPIC’s industry partner, NovaWurks, provided the space vehicle, which utilizes a small satellite platform assembled with a Hyper-Integrated Satlet, or HISat.
The HISat instruments are similar in nature to a child’s toy interlocking building blocks. They’re engineered to be built into larger structures called SensorCraft. Those SensorCraft can share resources with multiple payloads and conform to different sizes and shapes to accommodate them. This easily configurable, building-block architecture allows a lot of flexibility with payload designs and concepts, ultimately giving payload providers easier, less expensive access to space and increased maneuverability between multiple orbits.
Scientists at NASA’s Langley Research Center in Hampton, Virginia, designed and built the Athena sensor payload, which consists of an optical module, a calibration module, and a newly developed sensor electronics assembly. Athena EPIC’s sensor was built with spare parts from NASA’s CERES (Clouds and the Earth’s Radiant Energy System) mission. Several different generations of CERES satellite and space station instruments have tracked Earth’s radiation budget.
“Instead of Athena carrying its own processor, we’re using the processors on the HISats to control things like our heaters and do some of the control functions that typically would be done by a processor on our payload,” said Kory Priestley, principal investigator for Athena EPIC from NASA Langley. “So, this is merging an instrument and a satellite platform into what we are calling a SensorCraft. It’s a more integrated approach. We don’t need as many capabilities built into our key instrument because it’s being brought to us by the satellite host. We obtain greater redundancy, and it simplifies our payload.”
This is the first HISat mission led by NASA. Traditional satellites, like the ones that host the CERES instruments — are large, sometimes the size of a school bus, and carry multiple instruments. They tend to be custom units built with all of their own hardware and software to manage control, propulsion, cameras, carousels, processors, batteries, and more, and sometimes even require two of everything to guard against failures in the system. All of these factors, plus the need for a larger launch vehicle, significantly increase costs.
This transformational approach to getting instruments into space can reduce the cost from billions to millions per mission. “Now we are talking about something much smaller — SensorCraft the size of a mini refrigerator,” said Priestley. “If you do have failures on orbit, you can replace these much more economically. It’s a very different approach moving forward for Earth observation.”
Athena EPIC is scheduled to launch July 22 as a rideshare on a SpaceX Falcon 9 rocket from Vandenberg Space Force Base, California. The primary NASA payload on the launch will be the TRACERS (Tandem Reconnection and Cusp Electrodynamics Reconnaissance Satellites) mission. The TRACERS mission is led by the University of Iowa for NASA’s Heliophysics Division within the Science Mission Directorate. NASA’s Earth Science Division also provided funding for Athena EPIC.
“Langley Research Center has long been a leader in developing remote sensing instruments for in-orbit satellites. As satellites become smaller, a less traditional, more efficient path to launch is needed in order to decrease complexity while simultaneously increasing the value of exploration, science, and technology measurements for the Nation,” added Turner.
For more information on NASA’s Athena EPIC mission:
https://science.nasa.gov/misshttps://science.nasa.gov/mission/athena/ion/athena/
About the Author
Charles G. Hatfield
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Curiosity Blog, Sols 4602-4603: On Top of the Ridge
Written by Alex Innanen, Atmospheric Scientist at York University
Earth planning date: Wednesday, July 16, 2025
As we hoped, we successfully climbed the 11-meter ramp (about 36 feet) and have arrived at the top of the ridge and the start of the main boxwork region. This means we’re moving into the next phase of the boxwork campaign, which is all about assessing these features and how we can navigate our way through them, and learning everything we can about their composition.
In support of that, we’re taking a good look around at the boxwork ridges with both ChemCam and Mastcam. Both instruments are taking mosaics of the more distant ridges to get a broader view of their features. A bit closer in, Mastcam has three more mosaics: two looking at different views of “El Corral” and “Chapare,” both of which we saw in Monday’s plan, and “Meson,” which is the ridge we’ll be heading for in today’s 15-meter drive (about 49 feet).
It’s not all looking ahead, though. The workspace in front of us has a lot to offer as well. Mastcam will be turning its sights to some nearby linear features. Our workspace is also full of nodular bedrock, which is getting lots of up-close attention. ChemCam will be turning its LIBS laser on a target called “Altamora,” and MAHLI and APXS will be examining another target called “Nocarane.”
With all the geological excitement, we can still manage to squeeze in some time to keep an eye on the environment. Though we don’t always mention them, REMS, RAD, and DAN are always there working steadily away to build up our understanding of Mars’ environment. We’ll also round out the plan with a suprahorizon cloud movie and a 360-degree dust-devil survey.
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Stay Cool: NASA Tests Innovative Technique for Super Cold Fuel Storage
In the vacuum of space, where temperatures can plunge to minus 455 degrees Fahrenheit, it might seem like keeping things cold would be easy. But the reality is more complex for preserving ultra-cold fluid propellants – or fuel – that can easily overheat from onboard systems, solar radiation, and spacecraft exhaust. The solution is a method called cryogenic fluid management, a suite of technologies that stores, transfers, and measures super cold fluids for the surface of the Moon, Mars, and future long-duration spaceflight missions.
Super cold, or cryogenic, fluids like liquid hydrogen and liquid oxygen are the most common propellants for space exploration. Despite its chilling environment, space has a “hot” effect on these propellants because of their low boiling points – about minus 424 degrees Fahrenheit for liquid hydrogen and about minus 298 for liquid oxygen – putting them at risk of boiloff.
In a first-of-its-kind demonstration, teams at NASA’s Marshall Space Flight Center in Huntsville, Alabama, are testing an innovative approach to achieve zero boiloff storage of liquid hydrogen using two stages of active cooling which could prevent the loss of valuable propellant.
“Technologies for reducing propellant loss must be implemented for successful long-duration missions to deep space like the Moon and Mars,” said Kathy Henkel, acting manager of NASA’s Cryogenic Fluid Management Portfolio Project, based at NASA Marshall. “Two-stage cooling prevents propellant loss and successfully allows for long-term storage of propellants whether in transit or on the surface of a planetary body.”
The new technique, known as “tube on tank” cooling, integrates two cryocoolers, or cooling devices, to keep propellant cold and thwart multiple heat sources. Helium, chilled to about minus 424 degrees Fahrenheit, circulates through tubes attached to the outer wall of the propellant tank.
Teams installed the propellant tank in a test stand at NASA Marshall in early June, and the 90-day test campaign is scheduled to conclude in September. The tank is wrapped in a multi-layer insulation blanket that includes a thin aluminum heat shield fitted between layers. A second set of tubes, carrying helium at about minus 298 Fahrenheit, is integrated into the shield. This intermediate cooling layer intercepts and rejects incoming heat before it reaches the tank, easing the heat load on the tube-on-tank system.
To prevent dangerous pressure buildup in the propellant tank in current spaceflight systems, boiloff vapors must be vented, resulting in the loss of valuable fuel. Eliminating such propellant losses is crucial to the success of NASA’s most ambitious missions, including future crewed journeys to Mars, which will require storing large amounts of cryogenic propellant in space for months or even years. So far, cryogenic fuels have only been used for missions lasting less than a week.
“To go to Mars and have a sustainable presence, you need to preserve cryogens for use as rocket or lander return propellant,” Henkel said. “Rockets currently control their propellant through margin, where larger tanks are designed to hold more propellant than what is needed for a mission. Propellant loss isn’t an issue with short trips because the loss is factored into this margin. But, human exploration missions to Mars or longer stays at the Moon will require a different approach because of the very large tanks that would be needed.”
The Cryogenic Fluid Management Portfolio Project is a cross-agency team based at NASA Marshall and the agency’s Glenn Research Center in Cleveland. The cryogenic portfolio’s work is under NASA’s Technology Demonstration Missions Program, part of NASA’s Space Technology Mission Directorate, and is comprised of more than 20 individual technology development activities.
Learn more about cryogenic fluid management:
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Preparations for Next Moonwalk Simulations Underway (and Underwater)
During the Tour de France, athletes have to maintain a constant speed while bike riding for dozens of miles through cold rains and summer heat. These cyclists need gear that adapts to the different environments they encounter. One company is using a material with NASA origins to ensure these athletes stay comfortable while taking their grand tours.
Phase-change materials use basic properties of matter to maintain a steady temperature. When a substance melts from a solid to a liquid, the material absorbs heat, and when it becomes solid again, it releases that heat. In the 1980s, Triangle Research Corporation received a NASA Small Business Innovation Research award to explore how phase-change materials could be incorporated into textiles to control temperatures in spacesuit gloves. By placing phase-change materials in small capsules woven throughout a textile, these temperature-regulating properties can be tuned to the comfort of the human body. While these textiles weren’t incorporated into any gloves flown on NASA missions, they formed the basis for a new product, sold under the name Outlast.
Outlast has since become one of the most widely distributed temperature-regulating fabrics, found in products such as bedding, loungewear, and office chairs. It has seen especially extensive use in activewear, ranging from jogging clothes to professional sports gear.
Founded in 2001 and based in Fréjus, France, the company Ekoï makes clothing and accessories for cyclists, particularly those who bike competitively. The company first encountered Outlast at the Performance Days fabric trade fair in Munich, Germany, and was impressed with its capabilities as well as its NASA heritage.
“When you say NASA, it’s always impressive.” said Celine Milan, director of textiles at Ekoï. “At the beginning we were even saying in here in our offices, ‘Wow, this technology was developed by NASA.’ It’s on another level.”
Ekoi’s Outlast line officially launched in July 2022, during that year’s Tour de France. Over the course of that race, the company found it improved cyclists’ performance in the event’s mountain stages, where elevation changes mean wide swings in temperature. It also improved athletes’ aerodynamics, as their jerseys could stay closed in warmer environments, rather than opening them to let in wind.
Today, Ekoï sells several products that incorporate Outlast materials, including jerseys, gloves, and socks. These products are internationally known for their NASA heritage. Whether engineering for astronaut’s comfort in space or competitive athletes, NASA aims for excellence.
Learn more about NASA’s Spinoff Technologies: https://spinoff.nasa.gov/
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A massive, spacetime-warping cluster of galaxies is the setting of today’s NASA/ESA Hubble Space Telescope image. The galaxy cluster in question is Abell 209, located 2.8 billion light-years away in the constellation Cetus (the Whale).
This Hubble image of Abell 209 shows more than a hundred galaxies, but there’s more to this cluster than even Hubble’s discerning eye can see. Abell 209’s galaxies are separated by millions of light-years, and the seemingly empty space between the galaxies is filled with hot, diffuse gas that is visible only at X-ray wavelengths. An even more elusive occupant of this galaxy cluster is dark matter: a form of matter that does not interact with light. Dark matter does not absorb, reflect, or emit light, effectively making it invisible to us. Astronomers detect dark matter by its gravitational influence on normal matter. Astronomers surmise that the universe is comprised of 5% normal matter, 25% dark matter, and 70% dark energy.
Hubble observations, like the ones used to create this image, can help astronomers answer fundamental questions about our universe, including mysteries surrounding dark matter and dark energy. These investigations leverage the immense mass of a galaxy cluster, which can bend the fabric of spacetime itself and create warped and magnified images of background galaxies and stars in a process called gravitational lensing.
While this image lacks the dramatic rings that gravitational lensing can sometimes create, Abell 209 still shows subtle signs of lensing at work, in the form of streaky, slightly curved galaxies within the cluster’s golden glow. By measuring the distortion of these galaxies, astronomers can map the distribution of mass within the cluster, illuminating the underlying cloud of dark matter. This information, which Hubble’s fine resolution and sensitive instruments help to provide, is critical for testing theories of how our universe evolved.
Text Credit: ESA/Hubble
Image credit: ESA/Hubble & NASA, M. Postman, P. Kelly
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Four crew members are preparing to launch to the International Space Station as part of NASA’s SpaceX Crew-11 mission to perform research, technology demonstrations, and maintenance activities aboard the orbiting laboratory.
During the mission, Crew-11 also will contribute to NASA’s Artemis campaign by simulating Moon landing scenarios that astronauts may encounter near the lunar South Pole, showing how the space station helps prepare crews for deep space human exploration. The simulations will be performed before, during, and after their mission using handheld controllers and multiple screens to identify how changes in gravity affect spatial awareness and astronauts’ ability to pilot spacecraft, like a lunar lander.
NASA astronauts Zena Cardman and Mike Fincke, JAXA (Japan Aerospace Exploration Agency) astronaut Kimiya Yui, and Roscosmos cosmonaut Oleg Platonov will lift off no earlier than 12:09 p.m. EDT on Thursday, July 31, from Launch Complex 39A at the agency’s Kennedy Space Center in Florida on a long-duration mission. The cadre will fly aboard a SpaceX Dragon spacecraft, named Endeavour, which previously flew NASA’s SpaceX Demo-2, Crew-2, Crew-6, and Crew-8 missions, as well as private astronaut mission Axiom Mission 1.
The flight is the 11th crew rotation mission with SpaceX to the space station as part of NASA’s Commercial Crew Program. Overall, the Crew-11 mission is the 16th crewed Dragon flight to the space station, including Demo-2 in 2020 and 11 operational crew rotations for NASA, as well as four private astronaut missions.
As support teams progress through Dragon preflight milestones for Crew-11, they also are preparing a SpaceX Falcon 9 rocket booster for its third flight. Once all rocket and spacecraft system checkouts are complete and all components are certified for flight, teams will mate Dragon to Falcon 9 in SpaceX’s hangar at the launch site. The integrated spacecraft and rocket will then be rolled to the pad and raised vertically for the crew’s dry dress rehearsal and an integrated static fire test before launch.
Meet Crew-11
Selected as a NASA astronaut in 2017, Cardman will conduct her first spaceflight. The Williamsburg, Virginia, native holds a bachelor’s degree in biology and a master’s degree in marine sciences from the University of North Carolina at Chapel Hill. At the time of selection, she was pursuing a doctorate in geosciences. Cardman’s geobiology and geochemical cycling research focused on subsurface environments, from caves to deep sea sediments. Since completing initial training, Cardman has supported real-time station operations and lunar surface exploration planning. Follow @zenanaut on X and @zenanaut on Instagram.
This mission will be Fincke’s fourth trip to the space station, having logged 382 days in space and nine spacewalks during Expedition 9 in 2004, Expedition 18 in 2008, and STS-134 in 2011, the final flight of space shuttle Endeavour. Throughout the past decade, Fincke has applied his expertise to NASA’s Commercial Crew Program, advancing the development and testing of Dragon and Boeing’s Starliner spacecraft toward operational certification. The Emsworth, Pennsylvania, native is a graduate of the United States Air Force Test Pilot School and holds bachelors’ degrees from the Massachusetts Institute of Technology, Cambridge, in both aeronautics and astronautics, as well as Earth, atmospheric, and planetary sciences. He also has a master’s degree in aeronautics and astronautics from Stanford University in California. Fincke is a retired U.S. Air Force colonel with more than 2,000 flight hours in over 30 different aircraft. Follow @AstroIronMike on X and Instagram.
With 142 days in space, this mission will be Yui’s second trip to the space station. After his selection as a JAXA astronaut in 2009, Yui flew as a flight engineer for Expedition 44/45 and became the first Japanese astronaut to capture JAXA’s H-II Transfer Vehicle using the station’s robotic arm. In addition to constructing a new experimental environment aboard Kibo, he conducted a total of 21 experiments for JAXA. In November 2016, Yui was assigned as chief of the JAXA Astronaut Group. He graduated from the School of Science and Engineering at the National Defense Academy of Japan in 1992. He later joined the Air Self-Defense Force at the Japan Defense Agency (currently the Ministry of Defense). In 2008, Yui joined the Air Staff Office at the Ministry of Defense as a lieutenant colonel. Follow @astro_kimiya on X.
The mission will be Platonov’s first spaceflight. Before his selection as a cosmonaut in 2018, Platonov earned a degree in engineering from Krasnodar Air Force Academy in aircraft operations and air traffic management. He also earned a bachelor’s degree in state and municipal management in 2016 from the Far Eastern Federal University in Vladivostok, Russia. Assigned as a test cosmonaut in 2021, he has experience in piloting aircraft, zero gravity training, scuba diving, and wilderness survival.
Mission Overview
Following liftoff, Falcon 9 will accelerate Dragon to approximately 17,500 mph. Once in orbit, the crew, NASA, and SpaceX mission control will monitor a series of maneuvers that will guide Dragon to the forward-facing port of the station’s Harmony module. The spacecraft is designed to dock autonomously, but the crew can pilot it manually, if necessary.
After docking, Crew-11 will be welcomed aboard the station by the seven-member Expedition 73 crew, before conducting a short handover period on research and maintenance activities with the departing Crew-10 crew members. Then, NASA astronauts Anne McClain, Nichole Ayers, JAXA astronaut Takuya Onishi, and Roscosmos cosmonaut Kirill Peskov will undock from the space station and return to Earth. Ahead of Crew-10’s return, mission teams will review weather conditions at the splashdown sites off the coast of California before departure from the station.
Cardman, Fincke, and Yui will conduct scientific research to prepare for human exploration beyond low Earth orbit and benefit humanity on Earth. Participating crew members will simulate lunar landings, test strategies to safeguard vision, and advance other human spaceflight studies led by NASA’s Human Research Program. The crew also will study plant cell division and microgravity’s effects on bacteria-killing viruses, as well as perform experiments to produce a higher volume of human stem cells and generate on-demand nutrients.
While aboard the orbiting laboratory, Crew-11 will welcome a Soyuz spacecraft in November with three new crew members, including NASA astronaut Chris Williams. They also will bid farewell to the Soyuz carrying NASA astronaut Jonny Kim. The crew also is expected to see the arrival of the Dragon, Roscosmos Progress spacecraft, and Northrop Grumman’s Cygnus spacecraft to resupply the station.
NASA’s SpaceX Crew-11 mission will be aboard the International Space Station on Nov. 2, when the orbiting laboratory surpasses 25 years of a continuous human presence. Since the first crew expedition arrived, the space station has enabled more than 4,000 groundbreaking experiments in the unique microgravity environment, while becoming a springboard for building a low Earth orbit economy and preparing for NASA’s future exploration of the Moon and Mars.
Learn more about the space station, its research, and crew, at:
]]>Vision Changes on Space Station
Science in Space July 2025
When astronauts began spending six months and more aboard the International Space Station, they started to notice changes in their vision. For example, many found that, as their mission progressed, they needed stronger reading glasses. Researchers studying this phenomenon identified swelling in the optic disc, which is where the optic nerve enters the retina, and flattening of the eye shape. These symptoms became known as Space-Associated Neuro-Ocular Syndrome (SANS).
Microgravity causes a person’s blood and cerebrospinal fluid to shift toward the head and studies have suggested that these fluid shifts may be an underlying cause of SANS. A current investigation, Thigh Cuff, examines whether tight leg cuffs change the way fluid moves around inside the body, especially around the eyes and in the heart and blood vessels. If so, the cuffs could serve as a countermeasure against the problems associated with fluid shifts, including SANS. A simple and easy-to-use tool to counter the headward shift of body fluids could help protect astronauts on future missions to the Moon and Mars. The cuffs also could treat conditions on Earth that cause fluid to build up in the head or upper body, such as long-term bed rest and certain diseases.
Following fluid shifts
The Fluid Shifts investigation, conducted from 2015 through 2020, was the first to reveal changes in how blood drains from the brain in microgravity. Vision Impairment and Intracranial Pressure (VIIP) began testing the role those fluid shifts and resulting increased brain fluid pressure might play in the development of SANS. This research used a variety of measures including clinical eye exams with and without dilatation, imaging of the retina and associated blood vessels and nerves, noninvasive imaging to measure the thickness of retinal structures, and magnetic resonance imaging of the eye and optic nerve. In addition, approximately 300 astronauts completed questionnaires to document vision changes during their missions.
In one paper published from the research, scientists described how these imaging techniques have improved the understanding of SANS. The authors summarized emerging research on developing a head-mounted virtual reality display that can conduct multimodal, noninvasive assessment to help diagnose SANS.
Other researchers determined that measuring the optic nerve sheath diameter shows promise as a way to identify and quantify eye and vision changes during spaceflight. The paper also makes recommendations for standardizing imaging tools, measurement techniques, and other aspects of study design.
Another paper reported on an individual astronaut who had more severe than usual changes after a six-month spaceflight and certain factors that may have contributed. Researchers also observed improvement in the individual’s symptoms that may have been due to B vitamin supplementation and lower cabin carbon dioxide levels following departure of some crew members. While a single case does not allow researchers to determine cause and effect, the magnitude of the improvements suggest this individual may be more affected by environmental conditions such as carbon dioxide. This may have been the first attempt to mitigate SANS with inflight B vitamin supplementation.
Eyeball tissue stiffness
![This image has two parts. The top is an image with three bands of grey across the bottom half with different textures, the bottom two separated by a red dotted line and a yellow line and the middle and top bands separated by a thin white band underscored by a blue line. A green line traces the top edge. The upper half of the image is black. The bottom is a graph with the bottom axis marked “time[s]” and the left axis marked “AU.” Red and blue lines oscillate up and down across the bottom axis. A legend labels the blue line “Chroidal Thickness” and the red line “Oximeter Signal.”](https://www.nasa.gov/wp-content/uploads/2024/09/jsc2022e004236.jpg)
SANSORI, a CSA (Canadian Space Agency) investigation, used an imaging technique called Optical Coherence Tomography to examine whether reduced stiffness of eye tissue contributes to SANS. On Earth, changes in stiffness of the tissue around the eyeball have been associated with aging and conditions such as glaucoma and myopia. Researchers found that long-duration spaceflight affected the mechanical properties of eye tissues, which could contribute to the development of SANS. This finding could improve understanding of eye changes during spaceflight and in aging patients on Earth.
Genetic changes, artificial gravity
The MHU-8 investigation from JAXA (Japan Aerospace Exploration Agency), which examined changes in DNA and gene expression in mice after spaceflight, found changes in the optic nerve and retinal tissue. Researchers also found that artificial gravity may reduce these changes and could serve as a countermeasure on future missions.
These and other studies ultimately could help researchers prevent, diagnose, and treat vision impairment in crew members and people on Earth.
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2 min read
Hubble Digs Up Galactic Time Capsule
This NASA/ESA Hubble Space Telescope image features the field of stars that is NGC 1786. The globular cluster is located in the Large Magellanic Cloud (LMC), a small satellite galaxy of the Milky Way Galaxy that is approximately 160,000 light-years away from Earth. NGC 1786 itself is in the constellation Dorado. It was discovered in the year 1835 by Sir John Herschel.
The data for this image comes from an observing program that compares old globular clusters in nearby dwarf galaxies — the LMC, the Small Magellanic Cloud, and the Fornax dwarf spheroidal galaxy — to globular clusters in the Milky Way galaxy. Our galaxy contains over 150 of these old, spherical collections of tightly-bound stars, which astronomers have studied in depth — especially with Hubble images like this one, which show them in previously unattainable detail. Being very stable and long-lived, globular clusters act as galactic time capsules, preserving stars from the earliest stages of a galaxy’s formation.
Astronomers once thought that stars in a globular cluster all formed together at about the same time, but the study of old globular clusters in our galaxy uncovered multiple populations of stars with different ages. To use globular clusters as historical markers, we must understand how they form and where these stars of varying ages come from. This observing program examined old globular clusters like NGC 1786 in these external galaxies to see if they, too, contain multiple populations of stars. This research can tell us more about how the LMC originally formed, but also the Milky Way Galaxy, too.
Text Credit: ESA/Hubble
Media Contact:
Claire Andreoli ([email protected])
NASA’s Goddard Space Flight Center, Greenbelt, MD
- Jupiter, Saturn, and Neptune each emit more energy than they receive from the Sun, meaning they have comparatively warm interiors.
- NASA’s Uranus flyby with Voyager 2 in 1986 found the planet colder than expected, which challenged ideas of how planets formed and evolved.
- However, with advanced computer modeling and a new look at old data, scientists think the planet may actually be warmer than previously expected.
For millennia, astronomers thought Uranus was no more than a distant star. It wasn’t until the late 18th century that Uranus was universally accepted as a planet. To this day, the ringed, blue world subverts scientists’ expectations, but new NASA research helps puzzle out some of the world’s mystique.
Uranus is unlike any other planet in our solar system. It spins on its side, which means each pole directly faces the Sun for a continuous 42-year “summer.” Uranus also rotates in the opposite direction of all planets except Venus. Data from NASA’s Voyager 2 Uranus flyby in 1986 also suggested the planet is unusually cold inside, challenging scientists to reconsider fundamental theories of how planets formed and evolved throughout our solar system.
“Since Voyager 2’s flyby, everybody has said Uranus has no internal heat,” said Amy Simon, a planetary scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “But it’s been really hard to explain why that is, especially when compared with the other giant planets.”
These Uranus projections came from only one up-close measurement of the planet’s emitted heat made by Voyager 2: “Everything hinges on that one data point,” said Simon. “That is part of the problem.”
Now, using an advanced computer modeling technique and revisiting decades of data, Simon and a team of scientists have found that Uranus does in fact generate some heat, as they reported on May 16 in the Monthly Notices of the Royal Astronomical Society journal.
A planet’s internal heat can be calculated by comparing the amount of energy it receives from the Sun to the amount it of energy it releases into space in the form of reflected light and emitted heat. The solar system’s other giant planets — Saturn, Jupiter, and Neptune — emit more heat than they receive, which means the extra heat is coming from inside, much of it left over from the high-energy processes that formed the planets 4.5 billion years ago. The amount of heat a planet exudes could be an indication of its age: the less heat released relative to the heat absorbed from the Sun, the older the planet is.
Uranus stood out from the other planets because it appeared to give off as much heat as it received, implying it had none of its own. This puzzled scientists. Some hypothesized that perhaps the planet is much older than all the others and has cooled off completely. Others proposed that a giant collision — the same one that may have knocked the planet on its side — blasted out all of Uranus’ heat. But none of these hypotheses satisfied scientists, motivating them to solve Uranus’ cold case.
“We thought, ‘Could it really be that there is no internal heat at Uranus?’” said Patrick Irwin, the paper’s lead author and professor of planetary physics at the University of Oxford in England. “We did many calculations to see how much sunshine is reflected by Uranus and we realized that it is actually more reflective than people had estimated.”
The researchers set out to determine Uranus’ full energy budget: how much energy it receives from the Sun compared to how much it reflects as sunlight and how much it emits as heat. To do this, they needed to estimate the total amount of light reflected from the planet at all angles. “You need to see the light that’s scattered off to the sides, not just coming straight back at you,” Simon said.
To get the most accurate estimate of Uranus’ energy budget yet, Oxford researchers developed a computer model that brought together everything known about Uranus’ atmosphere from decades of observations from ground- and space-based telescopes, including NASA’s Hubble Space Telescope and NASA’s Infrared Telescope Facility in Hawaii. The model included information about the planet’s hazes, clouds, and seasonal changes, all of which affect how sunlight is reflected and how heat escapes.
The researchers found that Uranus releases about 15% more energy than it receives from the Sun, a figure that is similar to another recent estimate from a separate study funded in part by NASA that was published July 14 in Geophysical Research Letters. These studies suggest Uranus it has its own heat, though still far less than its neighbor Neptune, which emits more than twice the energy it receives.
“Now we have to understand what that remnant amount of heat at Uranus means, as well as get better measurements of it,” Simon said.
Unraveling Uranus’ past is useful not only for mapping the timeline of when solar system planets formed and migrated to their current orbits, but it also helps scientists better understand many of the planets discovered outside the solar system, called exoplanets, a majority of which are the same size as Uranus.
By Emma Friedman
NASA’s Goddard Space Flight Center, Greenbelt, Md.
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Preparations for Next Moonwalk Simulations Underway (and Underwater)
NASA/Jacob Shaw
NASA’s X-59 quiet supersonic research aircraft has officially begun taxi tests, marking the first time this one-of-a-kind experimental aircraft has moved under its own power.
NASA test pilot Nils Larson and the X-59 team, made up of NASA and contractor Lockheed Martin personnel, completed the aircraft’s first low-speed taxi test at U.S. Air Force Plant 42 in Palmdale, California, on July 10, 2025.
The taxiing represents the X-59’s last series of ground tests before first flight. Over the coming weeks, the aircraft will gradually increase its speed, leading up to a high-speed taxi test that will take the aircraft just short of the point where it would take off.
During the low-speed tests, engineers and flight crews monitored how the X-59 handled as it moved across the runway, working to validate critical systems like steering and braking. These checks help ensure the aircraft’s stability and control across a range of conditions, giving pilots and engineers confidence that all systems are functioning as expected.
The X-59 is the centerpiece of NASA’s Quesst mission, which aims to demonstrate quiet supersonic flight by reducing the loud sonic boom to a quieter “thump.” Data gathered from the X-59 will be shared with U.S. and international regulators to inform the establishment of new, data-driven acceptable noise thresholds related to supersonic commercial flight over land.
