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NASA astronaut Anil Menon poses for a portrait at NASA’s Johnson Space Center in Houston. Credit: NASA/Josh Valcarcel NASA astronaut Anil Menon will embark on his first mission to the International Space Station, serving as a flight engineer and Expedition 75 crew member.
Menon will launch aboard the Roscosmos Soyuz MS-29 spacecraft in June 2026, accompanied by Roscosmos cosmonauts Pyotr Dubrov and Anna Kikina. After launching from the Baikonur Cosmodrome in Kazakhstan, the trio will spend approximately eight months aboard the orbiting laboratory.
During his expedition, Menon will conduct scientific investigations and technology demonstrations to help prepare humans for future space missions and benefit humanity.
Selected as a NASA astronaut in 2021, Menon graduated with the 23rd astronaut class in 2024. After completing initial astronaut candidate training, he began preparing for his first space station flight assignment.
Menon was born and raised in Minneapolis and is an emergency medicine physician, mechanical engineer, and colonel in the United States Space Force. He holds a bachelor’s degree in neurobiology from Harvard University in Cambridge, Massachusetts, a master’s degree in mechanical engineering, and a medical degree from Stanford University in California. Menon completed his emergency medicine and aerospace medicine residency at Stanford and the University of Texas Medical Branch in Galveston.
In his spare time, he still practices emergency medicine at Memorial Hermann’s Texas Medical Center and teaches residents at the University of Texas’ residency program. Menon served as SpaceX’s first flight surgeon, helping to launch the first crewed Dragon spacecraft on NASA’s SpaceX Demo-2 mission and building SpaceX’s medical organization to support humans on future missions. He served as a crew flight surgeon for both SpaceX flights and NASA expeditions aboard the space station.
For nearly 25 years, people have lived and worked continuously aboard the International Space Station, advancing scientific knowledge and conducting critical research for the benefit of humanity and our home planet. Space station research supports the future of human spaceflight as NASA looks toward deep space missions to the Moon under the Artemis campaign and in preparation for future human missions to Mars, as well as expanding commercial opportunities in low Earth orbit and beyond.
Learn more about International Space Station at:
https://www.nasa.gov/station
-end-
Joshua Finch / Jimi Russell
Headquarters, Washington
202-358-1100
joshua.a.finch@nasa.gov / james.j.russell@nasa.gov
Shaneequa Vereen
Johnson Space Center, Houston
281-483-5111
shaneequa.y.vereen@nasa.gov
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Last Updated Jul 01, 2025 LocationNASA Headquarters Related Terms
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By NASA
7 min read
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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Explore This SectionScience Europa Clipper Europa: Ocean World Europa Clipper Home MissionOverview Facts History Timeline ScienceGoals Team SpacecraftMeet Europa Clipper Instruments Assembly Vault Plate Message in a Bottle NewsNews & Features Blog Newsroom Replay the Launch MultimediaFeatured Multimedia Resources About EuropaWhy Europa? Europa Up Close Ingredients for Life Evidence for an Ocean To view this video please enable JavaScript, and consider upgrading to a web browser that supports HTML5 video
Scientists think there is an ocean within Jupiter’s moon Europa. NASA-JPL astrobiologist Kevin Hand explains why scientists are so excited about the potential of this ice-covered world to answer one of humanity’s most profound questions. Scientists think there is an ocean within Jupiter’s moon Europa. NASA-JPL astrobiologist Kevin Hand explains why scientists are so excited about the potential of this ice-covered world to answer one of humanity’s most profound questions.
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Explore This SectionScience Europa Clipper Reddish Bands on Europa Europa Clipper Home MissionOverview Facts History Timeline ScienceGoals Team SpacecraftMeet Europa Clipper Instruments Assembly Vault Plate Message in a Bottle NewsNews & Features Blog Newsroom Replay the Launch MultimediaFeatured Multimedia Resources About EuropaWhy Europa? Europa Up Close Ingredients for Life Evidence for an Ocean This colorized image of Europa is a product of clear-filter grayscale data from one orbit of NASA’s Galileo spacecraft.NASA/JPL-Caltech/SETI Institute Downloads
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May 28, 2025
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This colorized image of Europa is a product of clear-filter grayscale data from one orbit of NASA’s Galileo spacecraft, combined with lower-resolution color data taken on a different orbit.
The blue-white terrains indicate relatively pure water ice, whereas the reddish areas contain water ice mixed with hydrated salts, potentially magnesium sulfate or sulfuric acid. The reddish material is associated with the broad band in the center of the image, as well as some of the narrower bands, ridges, and disrupted chaos-type features. It is possible that these surface features may have communicated with a global subsurface ocean layer during or after their formation.
Part of the terrain in this previously unreleased color view is seen in the monochrome image, PIA01125.
The image area measures approximately 101 by 103 miles (163 km by 167 km). The grayscale images were obtained on November 6, 1997, during the Galileo spacecraft’s 11th orbit of Jupiter, when the spacecraft was approximately 13,237 miles (21,700 kilometers) from Europa. These images were then combined with lower-resolution color data obtained in 1998, during the spacecraft’s 14th orbit of Jupiter, when the spacecraft was 89,000 miles (143,000 km) from Europa.
JPL is a division of the California Institute of Technology in Pasadena.
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Explore This SectionScience Europa Clipper Europa’s Stunning Surface Europa Clipper Home MissionOverview Facts History Timeline ScienceGoals Team SpacecraftMeet Europa Clipper Instruments Assembly Vault Plate Message in a Bottle NewsNews & Features Blog Newsroom Replay the Launch MultimediaFeatured Multimedia Resources About EuropaWhy Europa? Europa Up Close Ingredients for Life Evidence for an Ocean The puzzling, fascinating surface of Jupiter’s icy moon Europa looms large in this newly-reprocessed color view.NASA/JPL-Caltech/SETI Institute Downloads
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May 28, 2025
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The puzzling, fascinating surface of Jupiter’s icy moon Europa looms large in this newly-reprocessed color view, made from images taken by NASA’s Galileo spacecraft in the late 1990s. This is the color view of Europa from Galileo that shows the largest portion of the moon’s surface at the highest resolution.
The view was previously released as a mosaic with lower resolution and strongly enhanced color (see PIA02590). To create this new version, the images were assembled into a realistic color view of the surface that approximates how Europa would appear to the human eye.
The scene shows the stunning diversity of Europa’s surface geology. Long, linear cracks and ridges crisscross the surface, interrupted by regions of disrupted terrain where the surface ice crust has been broken up and re-frozen into new patterns.
Color variations across the surface are associated with differences in geologic feature type and location. For example, areas that appear blue or white contain relatively pure water ice, while reddish and brownish areas include non-ice components in higher concentrations. The polar regions, visible at the left and right of this view, are noticeably bluer than the more equatorial latitudes, which look more white. This color variation is thought to be due to differences in ice grain size in the two locations.
Images taken through near-infrared, green and violet filters have been combined to produce this view. The images have been corrected for light scattered outside of the image, to provide a color correction that is calibrated by wavelength. Gaps in the images have been filled with simulated color based on the color of nearby surface areas with similar terrain types.
This global color view consists of images acquired by the Galileo Solid-State Imaging (SSI) experiment on the spacecraft’s first and fourteenth orbits through the Jupiter system, in 1995 and 1998, respectively. Image scale is 1 mile (1.6 kilometers) per pixel. North on Europa is at right.
The Galileo mission was managed by NASA’s Jet Propulsion Laboratory in Pasadena, California, for the agency’s Science Mission Directorate in Washington. JPL is a division of the California Institute of Technology, Pasadena.
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