NASA astronaut Jessica Meir waves at the camera during a seven-hour, two-minute spacewalk outside the International Space Station on March 18, 2026.
Credit: NASA
NASA astronauts will venture outside the International Space Station on Tuesday, June 30, to replace a wrist joint on the orbital complex’s Canadarm2 robotic arm. The spacewalk is scheduled to begin at approximately 8 a.m. EDT.
Experts from NASA and CSA (Canadian Space Agency) will preview the upcoming spacewalk during a news conference at 2 p.m. on Thursday, June 25, on the agency’s YouTube channel. The briefing will take place at NASA’s Johnson Space Center in Houston. Learn how to watch NASA content through a variety of platforms, including social media.
Participants include:
Bill Spetch, operations and integration manager, International Space Station Program, NASA Johnson
Fiona Antkowiak, spacewalk flight director, NASA Johnson
Jason Dyer, deputy liaison manager, CSA
United States-based media interested in attending in person must contact the Johnson newsroom no later than 5 p.m. Wednesday, June 24, at: jsccommu@mail.nasa.gov. Media joining by phone should request dial‑in details by the same deadline. To ask a question, media must dial in no later than 15 minutes before the start of the news conference.
Tuesday, June 30
NASA astronauts Chris Williams and Jessica Meir will exit the station’s Quest airlock to replace a wrist joint that malfunctioned during normal Canadarm2 operations on May 27 after the arm drew elevated motor current and did not move as expected.
Watch NASA’s live U.S. spacewalk 95 coverage beginning at 6:30 a.m. EDT on NASA+, Amazon Prime, Netflix, and the agency’s YouTube channel. The spacewalk is expected to last roughly six-and-a-half hours.
NASA worked alongside CSA to understand the issue and determined a spacewalk was required to replace the joint using a spare already aboard the space station. Repairs to robotics, like Canadarm2, are normal and expected after more than 25 years of continuous operations, as the system was designed with replaceable components and planned maintenance in mind.
This spacewalk will be the second for Williams and the fifth for Meir. Williams will serve as spacewalk crew member 1 and will wear a suit with red stripes. Meir will serve as crew member 2 and will wear an unmarked suit. It will be the 280th spacewalk in support of space station assembly, maintenance, and upgrades.
To learn more about International Space Station research, operations, and its crews, visit:
NASA’s Webb Finds Clues to Ancient, Distant Origin of Comet 3I/ATLAS
Researchers used the NIRSpec (Near-Infrared Spectrograph) instrument on NASA’s James Webb Space Telescope to map specific chemical contents of comet 3I/ATLAS as it moved away from the Sun. Full image shown below.
Credits: Image: NASA, ESA, CSA, STScI, Martin Cordiner (CUA, NASA-GSFC); Image Processing: Alyssa Pagan (STScI)
As interstellar comet 3I/ATLAS began moving away from the Sun in December 2025, astronomers took the opportunity to turn NASA’s powerful James Webb Space Telescope in its direction and capture detailed measurements of its chemical components. The comet was freshly warmed from its closest pass by the Sun, and its ancient ice had been converted to a bright coma of gas ideal for observation.
Webb captured detailed data, including chemical ratios of carbon and deuterium, also known as heavy hydrogen, that are not found in solar system comets. The results surprised researchers. Working backward, astronomers used the components that make up comet 3I/ATLAS to understand the environment in which it formed.
A paper detailing the findings published June 22 in the journal Nature.
Image: Interstellar Comet 3I/ATLAS (NIRSpec IFU)
Researchers used the NIRSpec (Near-Infrared Spectrograph) instrument on NASA’s James Webb Space Telescope to map specific chemical contents of comet 3I/ATLAS as it moved away from the Sun.
Image: NASA, ESA, CSA, STScI, Martin Cordiner (CUA, NASA-GSFC); Image Processing: Alyssa Pagan (STScI)
The comet’s name comes from its status as the third confirmed interstellar comet, meaning it originated outside the solar system, and the telescope that first spotted it, the NASA-funded ATLAS (Asteroid Terrestrial-impact Last Alert System).
“This was a unique opportunity to study an ancient object from the distant galaxy, probably pre-dating our Sun and solar system,” said astro-chemist Martin Cordiner of NASA’s Goddard Space Flight Center in Greenbelt, Maryland, and lead author of the study. “On the one hand, we get direct insight into that distant time and place, and on the other, we learn something about how unusual our own solar system may be.”
Cordiner and the research team joined astronomers from many sub-disciplines in taking the opportunity to get a look at 3I/ATLAS on its journey through the solar system. They received approval to interrupt Webb’s planned schedule of observations to make use of its NIRSpec (Near-Infrared Spectrograph) instrument to study the comet.
NIRSpec revealed exceptionally high levels of deuterium, about 30 times more than seen in solar system comets. This implies that 3I/ATLAS may have originated in a very cold system much earlier in the history of our galaxy. During its formation, the material that became incorporated into 3I/ATLAS was likely exposed to plenty of radiation, but not any long-term warmth that would have reprocessed its “heavy water” ice, with deuterium, into the type of H2O ice we are familiar with on Earth.
Image: 3I/ATLAS Compared to Solar System Comets
These graphs lay out the significant difference in composition between the interstellar comet 3I/ATLAS and comets originating in our solar system. This very specific data helps researchers build a picture of the comet’s original planetary system.
Illustration: NASA, ESA, CSA, Martin Cordiner (CUA, NASA-GSFC), Leah Hustak (STScI)
Additionally, NIRSpec showed only traces of carbon-13 compared to lighter-weight carbon-12. This also points to a very old origin for 3I/ATLAS, as stellar systems become enriched with carbon-13 over time as generations of stars are born and die in the galaxy. That is why there are higher levels of carbon-13 in our system, around our Sun, which formed relatively recently, 4.5 billion years ago.
The research team estimates that 3I/ATLAS could have formed as long as 10 to 12 billion years ago, during the universe’s “cosmic noon,” when star formation was at its height. Its young origin system was likely ensconced in a relatively cold, dense cloud. The abundance of heavy water shows that 3I/ATLAS spent its formative years in a deeply frozen state.
A separate study using the European Southern Observatory’s Very Large Telescope, led by astronomer Cyrielle Opitom of the University of Edinburgh, complements Webb’s findings with an analysis of 3I/ATLAS’s carbon and nitrogen varieties in the form of the chemical cyanide.
“For us as scientists, finding these rare isotopes is fascinating, but the bigger picture here is looking at the possibilities of prebiotic chemistry elsewhere in the galaxy,” said Stefanie Milam of NASA Goddard and co-author of the study with Cordiner. “So far, we know of only one place in the vast cosmos where chemical ingredients led to life – our solar system, our Earth. Analysis of these interstellar objects is a major step towards learning how common, or uncommon, the conditions for the evolution of life are in the universe.”
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).
The following sections contain links to download this article’s images and videos in all available resolutions followed by related information links, media contacts, and if available, research paper and Spanish translation links.
Related Images & Videos
Interstellar Comet 3I/ATLAS (NIRSpec IFU)
Researchers used the NIRSpec (Near-Infrared Spectrograph) instrument on NASA’s James Webb Space Telescope to map specific chemical contents of comet 3I/ATLAS as it moved away from the Sun.
3I/ATLAS Compared to Solar System Comets
These graphs lay out the significant difference in composition between the interstellar comet 3I/ATLAS and comets originating in our solar system. This very specific data helps researchers build a picture of the comet’s original planetary system.
Two large, partly snow-covered islands lie west of mainland Alaska. Sea ice fragments form swirling patterns in the ocean, and brown water lines part of the Alaskan coastline.
NASA Earth Observatory/Michala Garrison
A false-color satellite image shows two large islands west of mainland Alaska. Sea ice fragments appear light blue and form swirling patterns in the ocean. The land appears mostly light green, interrupted by many small ponds and a large river delta.
NASA Earth Observatory/Michala Garrison
Two large, partly snow-covered islands lie west of mainland Alaska. Sea ice fragments form swirling patterns in the ocean, and brown water lines part of the Alaskan coastline.
NASA Earth Observatory/Michala Garrison
A false-color satellite image shows two large islands west of mainland Alaska. Sea ice fragments appear light blue and form swirling patterns in the ocean. The land appears mostly light green, interrupted by many small ponds and a large river delta.
NASA Earth Observatory/Michala Garrison
natural color
false color
Sea ice fragments drift near Alaska’s Saint Lawrence and Nunivak islands and colorful water surrounds the Yukon Delta in natural-color (left) and false-color (right) images acquired with the MODIS (Moderate Resolution Imaging Spectroradiometer) on NASA’s Terra satellite on June 3, 2026. NASA Earth Observatory images by Michala Garrison.
When clouds parted in early June 2026, satellites glimpsed hints of summer’s approach in the Bering Sea off Alaska’s coast. Sea ice, broken into small fragments, took a few final spins on its way to melting completely, while rivers swollen with snowmelt washed sediment and organic material out to sea.
These images, acquired with the MODIS (Moderate Resolution Imaging Spectroradiometer) on NASA’s Terra satellite on June 3, 2026, capture the seasonal transition. A false-color view of the area (right) brings out features of the landscape that are more subtle in the natural-color scene (left), as human eyes would see it. In false color, the tundra and marsh vegetation appear green, and ice-free rivers and thermokarst lakes are dark blue. Sea ice and snow, where they still linger, appear light blue.
Amid the seasonal phenomena playing out in the images stand Saint Lawrence and Nunivak islands. Both have volcanic origins and are among the largest islands in the United States. They contain extensive basaltic lava flows forming small shield volcanoes, along with other features such as cinder cones and maars, or low-lying volcanic craters.
Saint Lawrence Island lies about 150 miles (240 kilometers) directly south of the Bering Strait, separating Alaska and the Russian Far East. It is one of the few pieces of the land bridge that connected Asia and North America during the Pleistocene that remain above water. Pack ice persisted along the northeast side of the island in early June, while other sea ice drifted and curled into intricate patterns with the winds and currents. The smaller the ice fragments, the wispier their swirling patterns appear when observed by satellites.
Brownish water, likely containing a mixture of suspended sediment and colored dissolved organic matter, lines the coast of mainland Alaska. The colorful water appears to enter the sea around the Yukon Delta, a vast wetland where the Yukon River branches into many circuitous channels. Sediment concentrations in this area typically increase starting in late May or early June. That’s after river ice has broken up and runoff from rain and snowmelt carries eroded material downstream.
NASA Earth Observatory images by Michala Garrison, using MODIS data from NASA EOSDIS LANCE and GIBS/Worldview. Story by Lindsey Doermann.
Downloads
June 3, 2026: Natural color
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June 3, 2026: False color
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References & Resources
Alaska Volcano Observatory, Nunivak Island. Accessed June 18, 2026.
Desert Field Test With NASA Advanced Rover Prototype
PIA26701
Credits: NASA/JPL-Caltech
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Desert Field Test With NASA Advanced Rover Prototype
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PIA26701 Figure A
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PIA26701 Figure B
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PIA26701 Figure C
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PIA26701 Figure D
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Description
A prototype four-wheel rover developed at NASA’s Jet Propulsion Laboratory with advanced mobility and robotic autonomy capabilities trundled across the Colorado Desert near Plaster City, California, during a field test in March 2026. Called ERNEST (Exploration Rover for Navigating Extreme Sloped Terrain), the rover served here as a testbed for autonomy software developed for a potential lunar mission requiring higher speeds and much greater mileage than can be achieved with current planetary rovers.
ERNEST was trailed by engineers as it traveled about 16 miles over the course of 37 hours of drive time. That’s more than 10 times the speed at which NASA’s Perseverance rover can navigate on Mars. The team also tested how well the rover traveled at dusk, dawn, and nighttime to simulate the experience of large terrain shadows in polar regions on the Moon.
Figure A
Figure A shows the rover traveling toward its shadow.
Figure B
Figure B shows two team members setting up illuminators on the rover at night.
Figure C
Figure C shows three team members observing the rover during its long-range traverse.
Figure D
Figure D shows the rover with one wheel up on a rock.
Work on ERNEST began in 2022 and was initially supported by JPL internal research and development funds. It is currently funded by NASA’s Mars Exploration Program and the agency’s Exploration Science Strategy Integration Office under its Science Mission Directorate in Washington. Caltech in Pasadena, California, manages JPL for NASA.
