Category: NASA

Source: NASA

NASA’s Chandra X-ray Observatory unveiled this new look at the galaxy NGC 4736, also known as Messier 94, on June 30, 2026. Messier 94 is a spiral galaxy with a bright inner ring around it, called a starburst ring, where new stars are forming, perhaps fueled by gas driven in the unique oval-shaped structure seen here.
In this image, X-rays of different wavelengths from Chandra (red, orange, and blue) are layered with a visible light image from astrophotographers using their telescopes on the ground (red, green, and blue).
Experience this image through sound.
Image credit: X-ray: NASA/CXC/SAO; Optical:Brian Brennan and Remi Lacasse; Image Processing: NASA/CXC/SAO/L. Frattare and K. Arcand

Source: NASA

NASA astronaut Chris Williams and Roscosmos cosmonauts Sergey Kud-Sverchkov and Sergei Mikaev are wrapping up their 241‑day mission aboard the International Space Station.
The crew and its Soyuz MS-28 spacecraft will undock from the orbiting laboratory’s Rassvet module at 3:02 a.m. EDT Sunday, July 26, heading for a parachute-assisted landing at 6:26 a.m. (3:26 p.m. local time) on the steppe of Kazakhstan, southeast of Dzhezkazgan.
NASA’s live return coverage will stream through a variety of platforms. Learn where to watch online:

NASA Live

Williams and his crewmates will complete 3,856 orbits and travel more than 102 million miles before returning to Earth. The flight marks the first mission for Williams and Mikaev and the second for Kud‑Sverchkov.
After landing, the crew will fly by helicopter to Karaganda, Kazakhstan, where recovery teams are based. Williams then will return to NASA’s Johnson Space Center in Houston, while Kud‑Sverchkov and Mikaev head back to their training base in Star City, Russia.
NASA’s live return coverage is as follows (all times Eastern and subject to change based on real-time operations):
Saturday, July 25
9:40 a.m. – Coverage of the Space Station Expedition 74/75 change of command ceremony begins.
Kud‑Sverchkov will transfer command of the orbital complex to NASA astronaut Jessica Meir. Expedition 75 officially begins when Soyuz MS‑28 undocks.
11:10 p.m. – Coverage of crew farewells and hatch closing begins.
11:30 p.m. – Hatch closing
Sunday, July 26
2:30 a.m. – Coverage of undocking begins.
3:02 a.m. – Undocking
5:15 a.m. – Coverage of deorbit and landing begins.
5:32 a.m. – Deorbit burn
6:26 a.m. – Landing
For more than 25 years, people have lived and worked continuously aboard the International Space Station, advancing scientific knowledge and making research breakthroughs not possible on Earth. The space station helps NASA understand and overcome the challenges of human spaceflight, expand commercial opportunities in low Earth orbit, and build on the foundation for long-duration missions to the Moon, as part of the Artemis program, and to Mars.
To learn more about International Space Station research, operations, and its crews, visit:
www.nasa.gov/station
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Joshua Finch / Jimi RussellHeadquarters, Washington202-358-1100joshua.a.finch@nasa.gov / james.j.russell@nasa.gov
Leah Cheshier / Anna SchneiderJohnson Space Center, Houston281-483-5111leah.d.cheshier@nasa.gov / anna.c.schneider@nasa.gov

Source: NASA

Following its liftoff from Cape Canaveral on July 21 aboard a SpaceX Falcon 9 rocket, the Mission Robotic Vehicle (MRV) hosting the NASA-supported Robotic Servicing of Geosynchronous Satellites (RSGS) payload is now en route to geosynchronous Earth orbit, where it will use its advanced robotics to service spacecraft.
RSGS leverages in-space robotics expertise from NASA, aligned with the agency’s broader goals to advance U.S. capabilities for in-space servicing, assembly, and manufacturing that can be applied to space commerce and exploration.

Funded by the Defense Advanced Research Projects Agency (DARPA), the RSGS program uses twin dexterous robotic arms designed and developed by the U.S. Naval Research Laboratory. DARPA provided the robotic arm assembly for integration onto Northrop Grumman’s MRV, the nation’s first multi-mission robotic in-space servicer. The spacecraft will inspect and upgrade satellites in orbit by installing small propulsion modules – called mission extension pods – extending the operational life of existing spacecraft for years.
RSGS brings together government agencies and industry to test advanced robotic systems in space. NASA’s Goddard Space Flight Center in Greenbelt, Maryland, began supporting the RSGS mission in 2024 under an interagency agreement with DARPA.
NASA’s contributions to the mission leverage its legacy of servicing missions including the Hubble Space Telescope servicing missions and the Robotic Refueling Missions on the International Space Station. NASA support to RSGS program includes the development of dynamic simulation and analysis tools, software analysis for performance verification, and a team of flight robot operators who will support highly technical procedures in orbit. Hundreds of satellites are in geosynchronous orbit. Of those, fully functional satellites are often decommissioned early because they run out of fuel or their equipment becomes obsolete.  RSGS establishes a critical U.S. capability to extend the lifetime of spacecraft in orbit, allowing for more innovative and cost-effective mission designs.
By Colleen WoutersNASA’s Goddard Space Flight Center, Greenbelt, Md.

Source: NASA

Media are invited to NASA’s Langley Research Center in Hampton, Virginia, on Friday, July 31, to attend a media tour and ribbon-cutting ceremony for the Flight Dynamics Research Facility, the agency’s first new wind tunnel in more than 40 years.
The event will include a brief media availability with:

NASA Administrator Jared Isaacman
Dr. Trina Dyal, center director, NASA Langley
Administrator Edward C. Forst, U.S. General Services Administration

This event is in person only and open to members of the media who are United States citizens or lawful permanent residents. Information about timing will be shared closer to the event. NASA’s media accreditation policy is available online.
Media requesting to participate in person must RSVP no later than 5 p.m. EDT on Wednesday, July 29. Media RSVPs must be sent to Kimiko Booker, kimiko.s.booker@nasa.gov, and Brittny McGraw, brittny.v.mcgraw@nasa.gov, with the following information:

Legal first and last names (must match government identification)
Email
Phone number
Job title and organization

The wind tunnel opening marks a major milestone in the evolution of NASA and the nation’s aeronautics and space research capabilities. The state-of-the-art facility will support research and technology development that will advance NASA’s aeronautics, exploration, and science goals, including establishing a sustained human presence on the lunar surface through the Artemis program and the development of a Moon Base.
Learn more about the Flight Dynamics Research Facility at:
https://go.nasa.gov/4yzKEGQ
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Camille Gallo / Rob MargettaHeadquarters, Washington202-358-1600camille.m.gallo@nasa.gov / robert.j.margetta@nasa.gov 
Kimiko Booker / Brittny McGrawNASA Langley, Hampton, Va.757-506-5939 / 757-769-3763kimiko.s.booker@nasa.gov / brittny.v.mcgraw@nasa.gov

Source: NASA

Media are invited to join NASA for a virtual news conference at 2 p.m. EDT, Wednesday, July 29, to preview the Nancy Grace Roman Space Telescope mission, scheduled to launch from the agency’s Kennedy Space Center in Florida on Sunday, Aug. 30.
NASA will stream this event live through a variety of platforms. Learn where to watch online: https://www.nasa.gov/live.
Participants in the briefing, who will provide an overview of the mission and its status, include:

Shawn Domagal-Goldman, director, Astrophysics Division, NASA Headquarters in Washington
Jackie Townsend, Roman telescope project manager, NASA’s Goddard Space Flight Center in Greenbelt, Maryland
Julie McEnery, Roman telescope senior project scientist, NASA Goddard
Jeremy Perkins, Roman telescope integration and test scientist, NASA Goddard

Media interested in participating by phone must RSVP no later than two hours prior to the start of the briefing to Rob Garner at rob.garner@nasa.gov. A copy of NASA’s media accreditation policy is online.  
Named after NASA’s first chief astronomer, the Nancy Grace Roman Space Telescope will have a deep, panoramic view of the cosmos, generating never-before-seen pictures that will revolutionize our understanding of the universe. The observatory will usher in a new era of cosmic surveys, unveiling troves of celestial objects and shedding light on some of the universe’s most profound mysteries, including phenomena we can’t see. Roman also will showcase cutting-edge technology, including a test of the most advanced technology ever flown in space to directly image planets around nearby stars, a key step in NASA’s search for life on other worlds.
The Roman telescope is managed at NASA Goddard with participation by the agency’s Jet Propulsion Laboratory in Southern California; Caltech/IPAC in Pasadena, California; the Space Telescope Science Institute in Baltimore; and a team of scientists from various research institutions. The primary industrial partners are BAE Systems Inc., L3Harris Technologies, and Teledyne Scientific & Imaging. Contributions to Roman also are made by ESA (European Space Agency), JAXA (Japan Aerospace Exploration Agency), the French space agency CNES (Centre National d’Études Spatiales), and the Max Planck Institute for Astronomy in Germany.
For more information about NASA’s Roman telescope, visit:
https://nasa.gov/roman
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Alise FisherHeadquarters, Washington202-358-2546alise.m.fisher@nasa.gov
Claire Andreoli / Rob GarnerGoddard Space Flight Center, Greenbelt, Md.301-286-1940 / 301-286-5687claire.andreoli@nasa.gov / rob.garner@nasa.gov

Source: NASA

NISAR’s L-Band Radar Reveals ‘Hummingbird’ in Antarctica

PIA26617 Figure A

Data from the Earth-orbiting U.S.-India NISAR (NASA-ISRO Synthetic Aperture Radar) satellite’s L-band radar was used to produce an image of Nunatak Zaterjavshijsja — a mountaintop in East Antarctica — poking out amid a stream of ice flowing northeast to the ocean. The obstruction causes stresses in the ice, heavily fracturing the surrounding surfaces with deep cracks, called crevasses, which show as sharp green lines in the image. Produced in August 2025, the image has been nicknamed “the hummingbird” by NISAR scientists. 
The colors show differences in the way polarized microwave signals, which vibrate in different directions, interact with and reflect from the ice. Over Antarctica, NISAR transmits radar waves toward Earth with a horizontal polarization. The orientation of the signals that return, either horizontal, vertical, or both, provide clues about the object or surface that reflected them.
Signals that come back with a horizontal polarization likely bounced off a more regular surface, such as smooth ice. Those signals appear magenta in the image. Signals that return with vertical polarization may have refracted as they partially penetrated the ice or scattered at different angles as they reflected off irregular surfaces, like the faces of crevasses. Called volume scattering, these observations are displayed in green.
The white represents areas in which both magenta and green signals scatter back strongly, a possible indication that there is an equal blend of surface and volume scattering.

Figure A is an annotated version of image.
Managed by Caltech, NASA’s Jet Propulsion Laboratory leads the United States component of the project and provided the satellite’s L-band SAR and antenna reflector. The spacecraft bus and its S-band SAR were provided by the Indian Space Research Organisation. The NISAR satellite is the first to carry two SAR instruments at different wavelengths, collecting data using the spacecraft’s giant drum-shaped reflector, which measures 39 feet (12 meters) wide — the largest radar antenna reflector NASA has ever sent into space.
To learn more about NISAR, visit:

NISAR

Source: NASA

Wildland fire activity in Canada ramped up in July 2026, a time of year when lightning ignitions typically increase, according to a seasonal outlook published by several North American fire agencies. The blazes sent smoke plumes pouring across the U.S. and Canada, affecting air quality in both countries.  
This animation tracks brown carbon, the organic aerosols emitted by fires that give smoke plumes their characteristic yellow, orange, and brown tint. Brown carbon is a major component of a fire’s PM2.5 emissions, a type of air pollution that can aggravate cardiovascular and respiratory conditions. Here, the plume drifts across North American skies from July 14 through July 20, 2026.
Data for the animation come from a version of the GEOS (Goddard Earth Observing System) model, which assimilates data from satellites, aircraft, and ground-based observing systems. In addition to satellite observations of aerosols and fires, the model also incorporates meteorological data such as air temperature, moisture, and winds to project the plume’s behavior.
On July 14, at the start of the animation, numerous fires had already cropped up, including more than 180 in Ontario and several in northern Minnesota. Winds carried the smoke southeast, and by July 15, skies turned hazy and air quality declined from southern Ontario in Canada to the Upper Midwest and Northeast in the U.S. July 16 and 17 saw air quality in many areas continue to plummet, including in Detroit, where it stayed in the hazardous range for several consecutive days. Toronto, Chicago, New York City, and Washington, D.C., saw air quality ranging from unhealthy to hazardous.
On July 19 and 20, smoke continued to affect air quality downwind, including in the Great Lakes region, according to the National Weather Service. Storms began clearing it away in parts of the East, where air quality improved to good or moderate. Meanwhile, fires in the Pacific Northwest began degrading air quality there. 
The brown carbon shown in this animation represents organic carbon that comes specifically from wildfire smoke. Wildfires also emit black carbon, or soot, which contributes to their PM2.5 output. Black carbon has long served as a tracer for smoke plumes, but human sources—such as vehicle exhaust and industrial combustion—produce it too, blending in with the black carbon from fires. The GEOS model has been able to make that distinction for brown carbon since February 2026, when an update enabled it to split organic carbon into its anthropogenic and biomass-burning components.

NASA Earth Observatory animation by Lauren Dauphin, using GEOS-FP data from the Global Modeling and Assimilation Office at NASA GSFC. Story by Kathryn Hansen.

The Conversation (2026, July 16) Yes, breathing wildfire smoke can harm your health – here’s what you can do to protect yourself. Accessed July 21, 2026.
NASA’s Global Modeling and Assimilation Office (2026, February 19) Splitting Anthropogenic and Biomass Burning Sources of Organic Carbon in GOCART-2G. Accessed July 21, 2026.
NASA’s Scientific Visualization Studio (2026, July 20) Long-range Transport of 2026 Canadian Wildfire Smoke into the United States (July 14-20, 2026). Accessed July 21, 2026.
National Interagency Fire Center, Natural Resources Canada, and Servicio Meteorológico Nacional (2026, July 14) North American Seasonal Fire Assessment and Outlook. Accessed July 21, 2026.
The New York Times (2026, July 19) When Will the Wildfire Smoke Clear? Accessed July 21, 2026.
U.S. Environmental Protection Agency (2026, July 14-20) AirNow: Interactive Map of Air Quality. Accessed July 21, 2026.

Source: NASA

Human exploration of Mars will expose crews to a persistent, fine particulate environment whose physicochemical properties and health implications remain only partly understood. Because no samples of authentic Martian airborne dust have been returned to Earth, NASA must rely on lunar dust toxicology, Martian regolith simulants, and extensive rover/lander geochemical and mineralogical datasets to develop an initial, risk‑informed Permissible Exposure Limit (PEL). The Johnson Space Center (JSC) Lunar and Martian Dust Risk Custodian, the JSC Toxicology group, and the OCHMO Standards team worked together to draft a preliminary standard for incorporation into NASA-STD-3001 NASA Spaceflight Human-System Standard, Volume 2: Human Factors, Habitability, and Environmental Health.
The Martian Dust Limit Working Group was assembled to review this draft standard and associated evidence. Across two working sessions in February 2026, panel members reviewed mission architecture drivers, the current scientific understanding of Martian dust composition, and the toxicological evidence base supporting the establishment of a Mars dust PEL. Discussions emphasized the critical interplay between dust standards and Mars mission design elements including Extravehicular Activity (EVA) cadence, dust ingress characteristics, and the performance of habitat environmental control systems; these features highlight the need for a limit that is conservative, verifiable, and adaptable as the Mars architecture evolves. Panel members for the Working Group were David Damby, Claire Horwell, Brian Hynek, Shaunna Morrison, and Joyce Tsuji; NASA presenters were Katie Borremans, Elizabeth Rampe, and Torin McCoy; the OCHMO organizers/moderators were Douglas Ebert, David Francisco, and Kim Lowe. The Working Group meetings were also attended by members of Space Medicine and Operations group and JSC Toxicology.

Evaluate NASA’s proposed derivation of this initial standard
The panel concluded that NASA’s approach to deriving a 30‑day continuous PEL of 0.1 mg/m³ is reasonable and appropriately conservative for early short‑stay missions. This value originates from the established lunar 30‑day PEL (0.4 mg/m³), reduced by a 3x database uncertainty factor to account for knowledge gaps in Martian dust toxicity, higher iron content, amorphous constituents, and differences between simulants and actual dust. Members supported this framework, noting that a continuous limit applied using measured time‑weighted averages is more practical than making assumptions tied to fixed dust clearance rates given the diversity of spacecraft designs. They also acknowledged that near‑term exposures will be peak‑driven (e.g., post‑EVA suit ingress) and therefore recommended that the standard explicitly address the need to manage short‑duration spikes.
Identify chemical constituents requiring further scrutiny
The panel affirmed that overall dust mass remains the primary near‑term engineering concern, but several chemical constituents warrant attention. Chromium 6+, manganese, and perchlorate were all considered low‑risk in the context of inhaled Martian dust, provided the overall dust PEL is applied (see below). However, perchlorate was recommended for broader agency‑level exposure management across multiple intake routes (e.g., ingestion due to in situ crop growth). Iron was discussed in detail due to its high abundance in Martian regolith and its potential to generate Reactive Oxygen Species (ROS), though current toxicology shows no clear link between iron‑driven ROS and pulmonary harm; still, knowledge gaps led the panel to prioritize iron for further study and potential Spacecraft Maximum Allowable Concentration (SMAC) development. Arsenic was judged unlikely to pose meaningful risk at present.
Weigh the merits of an overall dust limit versus separate SMACs
Chemical constituents embedded within Martian dust were evaluated with respect to whether independent SMACs are warranted. Based on rover observations indicating predominantly trivalent chromium, low airborne perchlorate, and manganese concentrations well below conservative SMAC thresholds at the proposed PEL, the group agreed that the overall dust limit is likely sufficiently protective for expected 30‑day missions. However, panel members advised that SMACs be maintained for select constituents such as perchlorate and manganese for mission‑planning crosschecks. From the requirement perspective, an overall Martian dust PEL approach was favored for practicality and clarity, with constituent-specific SMACs retained or developed only where they add tangible operational value.
Refine the standard’s technical language for operational use
The working group also refined the standard language to ensure clarity and consistency in implementation. Members recommended that the limit apply to a specified time‑weighted average measurement period but also making it explicit that the requirement is for protection during continuous exposure. They encouraged incorporation of peak‑exposure management within the rationale, and highlighted uncertainties related to iron content, nanophase iron, and oxidative potential so that future revisions can incorporate emerging scientific insight.

The new requirement established for NASA-STD-3001 is as follows:
[V2 6253] The system shall limit the concentrations of Martian dust particles less than 10 μm in size in the habitable atmosphere below a 24-hour time-weighted average of 0.1 mg/m3 during exposure scenarios lasting up to 30 days in duration.

Taken together, the working group’s deliberations reinforce that an initial Martian dust standard must balance conservatism with operational feasibility while accommodating architectural and scientific uncertainty. The proposed requirement provides a defensible, evidence‑informed foundation for design, verification, and risk communication. As additional Martian data and toxicological research become available, this standard should be periodically revisited to ensure continued protection of crew health during human exploration of Mars.

Source: NASA

A team of NASA-sponsored scientists and engineers has developed a novel approach to observing high-energy particles in the near-Earth space environment, incorporating miniaturized sensors into a compact, multi-view particle detection instrument unlike any before it. Built for NASA’s Relativistic Electron Atmospheric Loss (REAL) CubeSat mission, the innovative instrument (also called REAL) enables more complete measurements of how energetic particles are transported and lost in Earth’s radiation environment, opening the door to improved understanding of space weather effects in low Earth orbit (LEO) while also making these unparalleled observations accessible to future small, low-cost spacecraft.

Billions of high-energy charged particles are magnetically trapped around Earth in doughnut-shaped regions called the Van Allen radiation belts. These belts typically form two distinct zones: an inner belt dominated by high-energy protons and an outer belt composed primarily of energetic electrons. Together, they pose a persistent hazard to satellites throughout Earth orbit that modern society depends on, including GPS satellites, and satellites that provide telephone and internet services. The outer belt, in particular, contains so-called killer electrons — particles energetic enough to penetrate satellite shielding and trigger damaging electrical discharges or operational anomalies.
Because of these risks, scientists have spent decades working to better understand and predict how the radiation belts behave. But complicating that effort is how dynamic they can be, particularly the outer belt, where populations of energetic electrons can build up and then rapidly drop off. At times, these electrons are lost from the belts, sometimes plunging into Earth’s atmosphere in microbursts lasting just 100 milliseconds, and other times in longer events that unfold over minutes to hours.
“Radiation particles can be trapped in the Van Allen belts for long periods, going back and forth along magnetic field lines, but if some interaction directs them more closely along Earth’s magnetic field lines, they plunge into the atmosphere,” explained Thomas Sotirelis, a physicist at the Johns Hopkins Applied Physics Laboratory, where the REAL instrument was developed. Sotirelis is the originator of the REAL instrument’s sensor concept and serves as instrument scientist for the REAL mission.
These loss events, known as energetic electron precipitation (EEP), represent one of the primary ways electrons are lost from the radiation belts and play an important role in their dynamics. But while researchers have identified plasma waves as likely drivers of these events, the underlying physics — e.g., whether electron scattering occurs gradually through diffusive processes or rapidly through nonlinear interactions — is still uncertain.

Successfully launched on July 23, 2025, the REAL instrument can distinguish between these potential modes, making it possible to investigate their relative importance and determine which, if any, waves are responsible for electron fallout. Leveraging recent advancements in sensor miniaturization, the instrument includes three sensor heads — a low-, medium-, and high-energy head with two, five, and four simultaneous look directions, respectively — integrated with four electronic boards. Together, they occupy only about half of the REAL CubeSat and use a time resolution sufficient to resolve microbursts of electrons with energies ranging from 40 keV up to 2 MeV. As its parent 3U CubeSat flies in LEO, REAL points along Earth’s magnetic field and can simultaneously measure the quantity, energy, and angle of the particles as they fall into the atmosphere — a first-of-its-kind capability.
“Most CubeSats can observe particles from only a single direction, so they have to spin in order to build up a full picture — and that takes a few seconds, too slow to capture microbursts,” said space physicist Robyn Millan of Dartmouth College, who serves as the REAL mission principal investigator. “With REAL, we’ve managed to squeeze three sensors, each with multiple look directions, into the top of this 100-by-100-millimeter head, allowing us to capture those measurements all at once. We’re really proud of that.”
The high-energy head consists of a 30-millimeter-thick aluminum collimator with four apertures, each spanning 20 degrees of pitch angle. Each aperture connects to an active area on a solid-state detector (SSD) at the base. The medium-energy head similarly uses an SSD base but instead employs five active areas that connect to a 22-millimeter-thick aluminum collimator with five apertures, each spanning 20 degrees of pitch angle. The low-energy head, on the other hand, is a miniature electrostatic analyzer (ESA) consisting of titanium electrodes sandwiched between etched silicon selector slits. These lie on top of a microchannel plate (MCP). The low-energy head uses 36 apertures, two look directions (±40 degrees), and 15 channels to measure electrons with lower energies, from 1 keV to 40 keV.
The pitch-angle-resolved measurements from these different look directions make it possible to distinguish precipitating, quasi-trapped, and trapped electron populations from each other, on timescales as short as 20 milliseconds, thereby more accurately quantifying the rate of electron loss and its impact on Earth’s atmosphere.

Just as importantly, this novel capability demonstrates that measurements once requiring large, resource-intensive missions can now be achieved with compact, cost-effective instruments on small satellites. This shift enables new, more complex mission concepts and technologies and paves the way for CubeSat constellations that could continuously observe Earth’s radiation environment and help us to better protect the space-based systems modern society depends on.
All three sensor heads in REAL are still functioning nominally and continue to collect valuable science data. In fact, the REAL team recently fine-tuned the instrument (changing threshold settings, etc.) to improve its sensitivity.
Project Lead(s): Dr. Tom Sotirelis, Johns Hopkins Applied Physics Laboratory; Dr. Robyn Millan, Dartmouth College
Sponsoring Organization(s): NASA Heliophysics Division’s Heliophysics Flight Opportunities in Research and Technology (H-FORT) program

Source: NASA

This composite photo released on July 17, 2026, shows the crescent of Mars grow as NASA’s Psyche spacecraft approached the planet for a gravity assist.
Psyche flew by Mars on May 15, 2026, using the planet’s gravity to gain speed and slightly tilt its trajectory. The flyby also gave the team an opportunity to prep for the science they will be conducting when they reach the metal-rich asteroid Psyche in 2029.
Watch a timelapse of the encounter.
Image credit: NASA/JPL-Caltech/ASU