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Curiosity Navigation Curiosity Home Mission Overview Where is Curiosity? Mission Updates Science Overview Instruments Highlights Exploration Goals News and Features Multimedia Curiosity Raw Images Images Videos Audio Mosaics More Resources Mars Missions Mars Sample Return Mars Perseverance Rover Mars Curiosity Rover MAVEN Mars Reconnaissance Orbiter Mars Odyssey More Mars Missions Mars Home 3 min read
Curiosity Blog, Sols 4638-4640: Imaging Extravaganza Atop a Ridge
NASA’s Mars rover Curiosity acquired this image on Aug. 21, 2025, looking across the ridge that the rover is currently parked near the edge of, looking down into the “Thumb” region that mission planners hope to be exploring next week. Curiosity captured this image using its Left Navigation Camera on Sol 4636, or Martian day 4,636 of the MArs Science Laboratory mission, at 16:09:13 UTC. NASA/JPL-Caltech Written by Conor Hayes, Graduate Student at York University
Earth planning date: Friday, Aug. 22, 2025
Curiosity is continuing its winding path through the mysterious boxwork structures that have been a major focus of the last several months of the mission. After driving away from “Río Frío,” we are now parked on top of a ridge overlooking a topographic depression that we’ve nicknamed the “Thumb.” The image on this post shows that ridge running along the “thumb’s” edge. Our goal today is to characterize this ridge before we drive down into the Thumb.
Because we had a lot of power and three sols available to play around with, this weekend plan is packed with a lot of good science. The boxwork structures in our immediate vicinity get a lot of attention, with Mastcam images planned of the targets “Wallatiri,” “Wallatiri 2,” “Mojo,” “Samaipata,” “Fort Samaipata,” and “Río Lluta,” as well as a nearby trough. ChemCam will be taking LIBS measurements of both Samaipata and Fort Saaipata as well. Samaipata gets even more attention from MAHLI, in addition to the targets “Vitichi” and “Tartagalita,” both of which will also be observed by APXS.
The boxwork structures don’t get all of the fun today, though. In addition to all of the boxwork observations, Mastcam will be documenting the ChemCam AEGIS target from Monday’s plan, and will also be doing some more imaging of the “Mishe Mokwa” butte. The highlight of Mastcam’s work in this plan (at least in my opinion) is the large 44-image mosaic of the north crater rim, taking advantage of the particularly low dust content of the atmosphere at this time of year. ChemCam will be taking several RMI images of Mishe Mokwa and a distant outcrop at “Dragones” that we will be driving towards over the next several months, as well as the usual post-drive AEGIS.
Rounding out this plan is a collection of observations of the atmosphere. In addition to typical DAN, REMS, and RAD activities, Curiosity’s Navcams will be put to work with a dust-devil movie, dust-devil survey, five cloud movies, and two line-of-sight observations of the north crater rim. Mastcam also gets involved in the environmental fun with a tau to track the amount of dust in the air.
Even with all of these activities, we decided that we aren’t yet done with this area. The drive in today’s plan is a short bump of about 2 meters (about 6.6 feet), so we’re all looking forward to continuing our investigation of this ridge on Monday.
Want to read more posts from the Curiosity team?
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Explore Webb Webb News Latest News Latest Images Webb’s Blog Awards X (offsite – login reqd) Instagram (offsite – login reqd) Facebook (offsite- login reqd) Youtube (offsite) Overview About Who is James Webb? Fact Sheet Impacts+Benefits FAQ Science Overview and Goals Early Universe Galaxies Over Time Star Lifecycle Other Worlds Observatory Overview Launch Deployment Orbit Mirrors Sunshield Instrument: NIRCam Instrument: MIRI Instrument: NIRSpec Instrument: FGS/NIRISS Optical Telescope Element Backplane Spacecraft Bus Instrument Module Multimedia About Webb Images Images Videos What is Webb Observing? 3d Webb in 3d Solar System Podcasts Webb Image Sonifications Webb’s First Images Team International Team People Of Webb More For the Media For Scientists For Educators For Fun/Learning 6 Min Read Webb Narrows Atmospheric Possibilities for Earth-sized Exoplanet TRAPPIST-1 d
This artist’s concept depicts planet TRAPPIST-1 d passing in front of its turbulent star, with other members of the closely packed system shown in the background. Full illustration and caption show below. Credits:
NASA, ESA, CSA, Joseph Olmsted (STScI) The exoplanet TRAPPIST-1 d intrigues astronomers looking for possibly habitable worlds beyond our solar system because it is similar in size to Earth, rocky, and resides in an area around its star where liquid water on its surface is theoretically possible. But according to a new study using data from NASA’s James Webb Space Telescope, it does not have an Earth-like atmosphere.
“Ultimately, we want to know if something like the environment we enjoy on Earth can exist elsewhere, and under what conditions. While NASA’s James Webb Space Telescope is giving us the ability to explore this question in Earth-sized planets for the first time, at this point we can rule out TRAPPIST-1 d from a list of potential Earth twins or cousins,” said Caroline Piaulet-Ghorayeb of the University of Chicago and Trottier Institute for Research on Exoplanets (IREx) at Université de Montréal, lead author of the study published in The Astrophysical Journal.
Planet TRAPPIST-1 d
The TRAPPIST-1 system is located 40 light-years away and was revealed as the record-holder for most Earth-sized rocky planets around a single star in 2017, thanks to data from NASA’s retired Spitzer Space Telescope and other observatories. Due to that star being a dim, relatively cold red dwarf, the “habitable zone” or “Goldilocks zone” – where the planet’s temperature may be just right, such that liquid surface water is possible – lies much closer to the star than in our solar system. TRAPPIST-1 d, the third planet from the red dwarf star, lies on the cusp of that temperate zone, yet its distance to its star is only 2 percent of Earth’s distance from the Sun. TRAPPIST-1 d completes an entire orbit around its star, its year, in only four Earth days.
Webb’s NIRSpec (Near-Infrared Spectrograph) instrument did not detect molecules from TRAPPIST-1 d that are common in Earth’s atmosphere, like water, methane, or carbon dioxide. However, Piaulet-Ghorayeb outlined several possibilities for the exoplanet that remain open for follow-up study.
“There are a few potential reasons why we don’t detect an atmosphere around TRAPPIST-1 d. It could have an extremely thin atmosphere that is difficult to detect, somewhat like Mars. Alternatively, it could have very thick, high-altitude clouds that are blocking our detection of specific atmospheric signatures — something more like Venus. Or, it could be a barren rock, with no atmosphere at all,” Piaulet-Ghorayeb said.
Image: TRAPPIST-1 d (Artist’s Concept)
This artist’s concept depicts planet TRAPPIST-1 d passing in front of its turbulent star, with other members of the closely packed system shown in the background. The TRAPPIST-1 system is intriguing to scientists for a few reasons. Not only does the system have seven Earth-sized rocky worlds, but its star is a red dwarf, the most common type of star in the Milky Way galaxy. If an Earth-sized world can maintain an atmosphere here, and thus have the potential for liquid surface water, the chance of finding similar worlds throughout the galaxy is much higher. In studying the TRAPPIST-1 planets, scientists are determining the best methods for separating starlight from potential atmospheric signatures in data from NASA’s James Webb Space Telescope. The star TRAPPIST-1’s variability, with frequent flares, provides a challenging testing ground for these methods. NASA, ESA, CSA, Joseph Olmsted (STScI) The Star TRAPPIST-1
No matter what the case may be for TRAPPIST-1 d, it’s tough being a planet in orbit around a red dwarf star. TRAPPIST-1, the host star of the system, is known to be volatile, often releasing flares of high-energy radiation with the potential to strip off the atmospheres of its small planets, especially those orbiting most closely. Nevertheless, scientists are motivated to seek signs of atmospheres on the TRAPPIST-1 planets because red dwarf stars are the most common stars in our galaxy. If planets can hold on to an atmosphere here, under waves of harsh stellar radiation, they could, as the saying goes, make it anywhere.
“Webb’s sensitive infrared instruments are allowing us to delve into the atmospheres of these smaller, colder planets for the first time,” said Björn Benneke of IREx at Université de Montréal, a co-author of the study. “We’re really just getting started using Webb to look for atmospheres on Earth-sized planets, and to define the line between planets that can hold onto an atmosphere, and those that cannot.”
The Outer TRAPPIST-1 Planets
Webb observations of the outer TRAPPIST-1 planets are ongoing, which hold both potential and peril. On the one hand, Benneke said, planets e, f, g, and h may have better chances of having atmospheres because they are further away from the energetic eruptions of their host star. However, their distance and colder environment will make atmospheric signatures more difficult to detect, even with Webb’s infrared instruments.
“All hope is not lost for atmospheres around the TRAPPIST-1 planets,” Piaulet-Ghorayeb said. “While we didn’t find a big, bold atmospheric signature at planet d, there is still potential for the outer planets to be holding onto a lot of water and other atmospheric components.”
“As NASA leads the way in searching for life outside our solar system, one of the most important avenues we can pursue is understanding which planets retain their atmospheres, and why,” said Shawn Domagal-Goldman, acting director of the Astrophysics Division at NASA Headquarters in Washington. “NASA’s James Webb Space Telescope has pushed our capabilities for studying exoplanet atmospheres further than ever before, beyond extreme worlds to some rocky planets – allowing us to begin confirming theories about the kind of planets that may be potentially habitable. This important groundwork will position our next missions, like NASA’s Habitable Worlds Observatory, to answer a universal question: Are we alone?”
The James Webb Space Telescope is the world’s premier space science observatory. Webb is solving mysteries in our solar system, looking beyond to distant worlds around other stars, and probing the mysterious structures and origins of our universe and our place in it. Webb is an international program led by NASA with its partners, ESA (European Space Agency) and CSA (Canadian Space Agency).
To learn more about Webb, visit:
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Last Updated Aug 13, 2025 Editor Marty McCoy Contact Laura Betz laura.e.betz@nasa.gov Related Terms
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X-ray: NASA/CXC/RIT/A. Varga et al.; Illustration: NASA/CXC/SAO/M. Weiss; Image Processing: NASA/CXC/SAO/N. Wolk A star is unleashing a barrage of X-rays that is causing a closely-orbiting, young planet to wither away an astonishing rate, according to a new study using data from NASA’s Chandra X-ray Observatory and described in our latest press release. A team of researchers has determined that this planet will go from the size of Jupiter down to a small, barren world.
This graphic provides a visual representation of what astronomers think is happening around the star (known as TOI 1227) and a planet that is orbiting it at a fraction the distance between Mercury and the Sun. This “baby” planet, called TOI 1227 b, is just about 8 million years old, about a thousand times younger than our Sun. The main panel is an artist’s concept that shows the Jupiter-sized planet (lower left) around TOI 1227, which is a faint red star. Powerful X-rays from the star’s surface are tearing away the atmosphere of the planet, represented by the blue tail. The star’s X-rays may eventually completely remove the atmosphere.
The team used new Chandra data — seen in the inset — to measure the amounts of X-rays from TOI 1227 that are striking the planet. Using computer models of the effects of these X-rays, they concluded they will have a transformative effect, rapidly stripping away the planet’s atmosphere. They estimate that the planet is losing a mass equivalent to a full Earth’s atmosphere about every 200 years.
The researchers used different sets of data to estimate the age of TOI 1227 b. One method exploits measurements of how TOI 1227 b’s host star moves through space in comparison to nearby populations of stars with known ages. A second method compared the brightness and surface temperature of the star with theoretical models of evolving stars. The very young age of TOI 1227 b makes it the second youngest planet ever to be observed passing in front of its host star (a so-called transit). Previously the planet had been estimated by others to be about 11 million years old.
Of all the exoplanets astronomers have found with ages less than 50 million years, TOI 1227 b stands out for having the longest year and the host planet with the lowest mass. These properties, and the high dose of X-rays it is receiving, make it an outstanding target for future observations.
A paper describing these results has been accepted publication in The Astrophysical Journal and a preprint is available here. The authors of the paper are Attila Varga (Rochester Institute of Technology), Joel Kastner (Rochester Institute of Technology), Alexander Binks (University of Tubingen, Germany), Hans Moritz Guenther (Massachusetts Institute of Technology), and Simon J. Murphy (University of New South Wales Canberra in Australia).
NASA’s Marshall Space Flight Center in Huntsville, Alabama, manages the Chandra program. The Smithsonian Astrophysical Observatory’s Chandra X-ray Center controls science operations from Cambridge, Massachusetts, and flight operations from Burlington, Massachusetts.
Read more from NASA’s Chandra X-ray Observatory Learn more about the Chandra X-ray Observatory and its mission here:
https://www.nasa.gov/chandra
https://chandra.si.edu
Visual Description
This release features an artist’s illustration of a Jupiter-sized planet closely orbiting a faint red star. An inset image, showing the star in X-ray light from Chandra, is superimposed on top of the illustration at our upper left corner.
At our upper right, the red star is illustrated as a ball made of intense fire. The planet, slightly smaller than the star, is shown at our lower left. Powerful X-rays from the star are tearing away the atmosphere of the planet, causing wisps of material to flow away from the planet’s surface in the opposite direction from the star. This gives the planet a slight resemblance to a comet, complete with a tail.
X-ray data from Chandra, presented in the inset image, shows the star as a small purple orb on a black background. Astronomers used the Chandra data to measure the amount of X-rays striking the planet from the star. They estimate that the planet is losing a mass equivalent to a full Earth’s atmosphere about every 200 years, causing it to ultimately shrink from the size of Jupiter down to a small, barren world.
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Megan Watzke
Chandra X-ray Center
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617-496-7998
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Corinne Beckinger
Marshall Space Flight Center, Huntsville, Alabama
256-544-0034
corinne.m.beckinger@nasa.gov
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Last Updated Jul 16, 2025 EditorLee MohonContactCorinne M. Beckingercorinne.m.beckinger@nasa.gov Related Terms
Astrophysics Chandra X-Ray Observatory Exoplanet Science Exoplanets Marshall Astrophysics Marshall Space Flight Center Science & Research Studying Exoplanets The Universe Explore More
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NASA Citizen Science and Your Career: Stories of Exoplanet Watch Volunteers
Doing NASA Science brings many rewards. But can taking part in NASA citizen science help your career? To find out, we asked participants in NASA’s Exoplanet Watch project about their experiences. In this project, amateur astronomers work together with professionals to track planets around other stars.
First, we heard from professional software programmers. Right away, one of them told us about getting a new job through connections made in the project.
“I decided to create the exoplanet plugin, [for citizen science] since it was quite a lot of manual work to check which transits were available for your location. The exoplanet plugin and its users got me in contact with the Stellar group… Through this group, I got into contact with a company called OurSky and started working for them… the point is, I created a couple of plugins for free and eventually got a job at an awesome company.”
Another participant talked about honing their skills and growing their confidence through Exoplanet Watch.
“There were a few years when I wasn’t actively coding. However, Exoplanet Watch rekindled that spark…. Participating in Exoplanet Watch even gave me the confidence to prepare again for a technical interview at Meta—despite having been thoroughly defeated the first time I tried.”
Teachers and teaching faculty told us how Exoplanet Watch gives them the ability to better convey what scientific research is all about – and how the project motivates students!
“Exoplanet Watch makes it easy for undergraduate students to gain experience in data science and Python, which are absolutely necessary for graduate school and many industry jobs.”
“Experience with this collaborative work is a vital piece of the workforce development of our students who are seeking advanced STEM-related careers or ongoing education in STEM (Science, Technology, Engineering, & Mathematics) fields after graduation… Exoplanet Watch, in this way, is directly training NASA’s STEM workforce of tomorrow by allowing CUNY (The City University of New York) students to achieve the science goals that would otherwise be much more difficult without its resources.”
One aspiring academic shared how her participation on the science team side of the project has given her research and mentorship experience that strengthens her resume.
“I ended up joining the EpW team to contribute my expertise in stellar variability… My involvement with Exoplanet Watch has provided me with invaluable experience in mentoring a broad range of astronomy enthusiasts and working in a collaborative environment with people from around the world. … Being able to train others, interact in a team environment, and work independently are all critical skills in any work environment, but these specific experiences have also been incredibly valuable towards building my portfolio as I search for faculty positions around the USA.”
There are no guarantees, of course. What you get out of NASA citizen science depends on what you put in. But there is certainly magic to be found in the Exoplanet Watch project. As one student said:
“Help will always be found at Hogwarts, to those who need it.” Exoplanet Watch was definitely Hogwarts for me in my career as an astronomer!”
For more information about NASA and your career, check out NASA’s Surprisingly STEM series highlighting exciting and unexpected jobs at NASA, or come to NASA Career Day, a virtual event for students and educators. Participants must register by September 4, 2025. The interactive platform will be open from September 15-19, with live panels and events taking place on September 18.
Exoplanet Watch volunteer Bryan Martin
Credit: Bryan Martin
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Last Updated Jul 16, 2025 Related Terms
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A New Alloy is Enabling Ultra-Stable Structures Needed for Exoplanet Discovery
A unique new material that shrinks when it is heated and expands when it is cooled could help enable the ultra-stable space telescopes that future NASA missions require to search for habitable worlds.
Advancements in material technologies are needed to meet the science needs of the next great observatories. These observatories will strive to find, identify, and study exoplanets and their ability to support life. Credit: NASA JPL One of the goals of NASA’s Astrophysics Division is to determine whether we are alone in the universe. NASA’s astrophysics missions seek to answer this question by identifying planets beyond our solar system (exoplanets) that could support life. Over the last two decades, scientists have developed ways to detect atmospheres on exoplanets by closely observing stars through advanced telescopes. As light passes through a planet’s atmosphere or is reflected or emitted from a planet’s surface, telescopes can measure the intensity and spectra (i.e., “color”) of the light, and can detect various shifts in the light caused by gases in the planetary atmosphere. By analyzing these patterns, scientists can determine the types of gasses in the exoplanet’s atmosphere.
Decoding these shifts is no easy task because the exoplanets appear very near their host stars when we observe them, and the starlight is one billion times brighter than the light from an Earth-size exoplanet. To successfully detect habitable exoplanets, NASA’s future Habitable Worlds Observatory will need a contrast ratio of one to one billion (1:1,000,000,000).
Achieving this extreme contrast ratio will require a telescope that is 1,000 times more stable than state-of-the-art space-based observatories like NASA’s James Webb Space Telescope and its forthcoming Nancy Grace Roman Space Telescope. New sensors, system architectures, and materials must be integrated and work in concert for future mission success. A team from the company ALLVAR is collaborating with NASA’s Marshall Space Flight Center and NASA’s Jet Propulsion Laboratory to demonstrate how integration of a new material with unique negative thermal expansion characteristics can help enable ultra-stable telescope structures.
Material stability has always been a limiting factor for observing celestial phenomena. For decades, scientists and engineers have been working to overcome challenges such as micro-creep, thermal expansion, and moisture expansion that detrimentally affect telescope stability. The materials currently used for telescope mirrors and struts have drastically improved the dimensional stability of the great observatories like Webb and Roman, but as indicated in the Decadal Survey on Astronomy and Astrophysics 2020 developed by the National Academies of Sciences, Engineering, and Medicine, they still fall short of the 10 picometer level stability over several hours that will be required for the Habitable Worlds Observatory. For perspective, 10 picometers is roughly 1/10th the diameter of an atom.
NASA’s Nancy Grace Roman Space Telescope sits atop the support structure and instrument payloads. The long black struts holding the telescope’s secondary mirror will contribute roughly 30% of the wave front error while the larger support structure underneath the primary mirror will contribute another 30%.
Credit: NASA/Chris Gunn
Funding from NASA and other sources has enabled this material to transition from the laboratory to the commercial scale. ALLVAR received NASA Small Business Innovative Research (SBIR) funding to scale and integrate a new alloy material into telescope structure demonstrations for potential use on future NASA missions like the Habitable Worlds Observatory. This alloy shrinks when heated and expands when cooled—a property known as negative thermal expansion (NTE). For example, ALLVAR Alloy 30 exhibits a -30 ppm/°C coefficient of thermal expansion (CTE) at room temperature. This means that a 1-meter long piece of this NTE alloy will shrink 0.003 mm for every 1 °C increase in temperature. For comparison, aluminum expands at +23 ppm/°C.
While other materials expand while heated and contract when cooled, ALLVAR Alloy 30 exhibits a negative thermal expansion, which can compensate for the thermal expansion mismatch of other materials. The thermal strain versus temperature is shown for 6061 Aluminum, A286 Stainless Steel, Titanium 6Al-4V, Invar 36, and ALLVAR Alloy 30.
Because it shrinks when other materials expand, ALLVAR Alloy 30 can be used to strategically compensate for the expansion and contraction of other materials. The alloy’s unique NTE property and lack of moisture expansion could enable optic designers to address the stability needs of future telescope structures. Calculations have indicated that integrating ALLVAR Alloy 30 into certain telescope designs could improve thermal stability up to 200 times compared to only using traditional materials like aluminum, titanium, Carbon Fiber Reinforced Polymers (CFRPs), and the nickel–iron alloy, Invar.
The hexapod assembly with six ALLVAR Alloy struts was measured for long-term stability. The stability of the individual struts and the hexapod assembly were measured using interferometry at the University of Florida’s Institute for High Energy Physics and Astrophysics. The struts were found to have a length noise well below the proposed target for the success criteria for the project. Credit: (left) ALLVAR and (right) Simon F. Barke, Ph.D. To demonstrate that negative thermal expansion alloys can enable ultra-stable structures, the ALLVAR team developed a hexapod structure to separate two mirrors made of a commercially available glass ceramic material with ultra-low thermal expansion properties. Invar was bonded to the mirrors and flexures made of Ti6Al4V—a titanium alloy commonly used in aerospace applications—were attached to the Invar. To compensate for the positive CTEs of the Invar and Ti6Al4V components, an NTE ALLVAR Alloy 30 tube was used between the Ti6Al4V flexures to create the struts separating the two mirrors. The natural positive thermal expansion of the Invar and Ti6Al4V components is offset by the negative thermal expansion of the NTE alloy struts, resulting in a structure with an effective zero thermal expansion.
The stability of the structure was evaluated at the University of Florida Institute for High Energy Physics and Astrophysics. The hexapod structure exhibited stability well below the 100 pm/√Hz target and achieved 11 pm/√Hz. This first iteration is close to the 10 pm stability required for the future Habitable Worlds Observatory. A paper and presentation made at the August 2021 Society of Photo-Optical Instrumentation Engineers conference provides details about this analysis.
Furthermore, a series of tests run by NASA Marshall showed that the ultra-stable struts were able to achieve a near-zero thermal expansion that matched the mirrors in the above analysis. This result translates into less than a 5 nm root mean square (rms) change in the mirror’s shape across a 28K temperature change.
The ALLVAR enabled Ultra-Stable Hexapod Assembly undergoing Interferometric Testing between 293K and 265K (right). On the left, the Root Mean Square (RMS) changes in the mirror’s surface shape are visually represented. The three roughly circular red areas are caused by the thermal expansion mismatch of the invar bonding pads with the ZERODUR mirror, while the blue and green sections show little to no changes caused by thermal expansion. The surface diagram shows a less than 5 nanometer RMS change in mirror figure. Credit: NASA’s X-Ray and Cryogenic Facility [XRCF] Beyond ultra-stable structures, the NTE alloy technology has enabled enhanced passive thermal switch performance and has been used to remove the detrimental effects of temperature changes on bolted joints and infrared optics. These applications could impact technologies used in other NASA missions. For example, these new alloys have been integrated into the cryogenic sub-assembly of Roman’s coronagraph technology demonstration. The addition of NTE washers enabled the use of pyrolytic graphite thermal straps for more efficient heat transfer. ALLVAR Alloy 30 is also being used in a high-performance passive thermal switch incorporated into the UC Berkeley Space Science Laboratory’s Lunar Surface Electromagnetics Experiment-Night (LuSEE Night) project aboard Firefly Aerospace’s Blue Ghost Mission 2, which will be delivered to the Moon through NASA’s CLPS (Commercial Lunar Payload Services) initiative. The NTE alloys enabled smaller thermal switch size and greater on-off heat conduction ratios for LuSEE Night.
Through another recent NASA SBIR effort, the ALLVAR team worked with NASA’s Jet Propulsion Laboratory to develop detailed datasets of ALLVAR Alloy 30 material properties. These large datasets include statistically significant material properties such as strength, elastic modulus, fatigue, and thermal conductivity. The team also collected information about less common properties like micro-creep and micro-yield. With these properties characterized, ALLVAR Alloy 30 has cleared a major hurdle towards space-material qualification.
As a spinoff of this NASA-funded work, the team is developing a new alloy with tunable thermal expansion properties that can match other materials or even achieve zero CTE. Thermal expansion mismatch causes dimensional stability and force-load issues that can impact fields such as nuclear engineering, quantum computing, aerospace and defense, optics, fundamental physics, and medical imaging. The potential uses for this new material will likely extend far beyond astronomy. For example, ALLVAR developed washers and spacers, are now commercially available to maintain consistent preloads across extreme temperature ranges in both space and terrestrial environments. These washers and spacers excel at counteracting the thermal expansion and contraction of other materials, ensuring stability for demanding applications.
For additional details, see the entry for this project on NASA TechPort.
Project Lead: Dr. James A. Monroe, ALLVAR
The following NASA organizations sponsored this effort: NASA Astrophysics Division, NASA SBIR Program funded by the Space Technology Mission Directorate (STMD).
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Last Updated Jul 01, 2025 Related Terms
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