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By NASA
6 min read
NASA’s IMAP Mission to Study Boundaries of Our Home in Space
Summary
NASA’s new Interstellar Mapping and Acceleration Probe, or IMAP, will launch no earlier than Tuesday, Sept. 23 to study the heliosphere, a giant shield created by the Sun. The mission will chart the heliosphere’s boundaries to help us better understand the protection it offers life on Earth and how it changes with the Sun’s activity. The IMAP mission will also provide near real-time measurements of the solar wind, data that can be used to improve models predicting the impacts of space weather ranging from power-line disruptions to loss of satellites, to the health of voyaging astronauts. Space is a dangerous place — one that NASA continues to explore for the benefit of all. It’s filled with radiation and high-energy particles that can damage DNA and circuit boards alike. Yet life endures in our solar system in part because of the heliosphere, a giant bubble created by the Sun that extends far beyond Neptune’s orbit.
With NASA’s new Interstellar Mapping and Acceleration Probe, or IMAP, launching no earlier than Tuesday, Sept. 23, humanity is set to get a better look at the heliosphere than ever before. The mission will chart the boundaries of the heliosphere to help us better understand the protection it offers and how it changes with the Sun’s activity. The IMAP mission will also provide near real-time measurements of space weather conditions essential for the Artemis campaign and deep space travel.
“With IMAP, we’ll push forward the boundaries of knowledge and understanding of our place not only in the solar system, but our place in the galaxy as a whole,” said Patrick Koehn, IMAP program scientist at NASA Headquarters in Washington. “As humanity expands and explores beyond Earth, missions like IMAP will add new pieces of the space weather puzzle that fills the space between Parker Solar Probe at the Sun and the Voyagers beyond the heliopause.”
Download this video from NASA’s Scientific Visualization Studio.
Domain of Sun
The heliosphere is created by the constant outflow of material and magnetic fields from the Sun called the solar wind. As the solar system moves through the Milky Way, the solar wind’s interaction with interstellar material carves out the bubble of the heliosphere. Studying the heliosphere helps scientists understand our home in space and how it came to be habitable.
As a modern-day celestial cartographer, IMAP will map the boundary of our heliosphere and study how the heliosphere interacts with the local galactic neighborhood beyond. It will chart the vast range of particles, dust, ultraviolet light, and magnetic fields in interplanetary space, to investigate the energization of charged particles from the Sun and their interaction with interstellar space.
The IMAP mission builds on NASA’s Voyager and IBEX (Interstellar Boundary Explorer) missions. In 2012 and 2018, the twin Voyager spacecraft became the first human-made objects to cross the heliosphere’s boundary and send back measurements from interstellar space. It gave scientists a snapshot of what the boundary looked like and where it was in two specific locations. While IBEX has been mapping the heliosphere, it has left many questions unanswered. With 30 times higher resolution and faster imaging, IMAP will help fill in the unknowns about the heliosphere.
Energetic neutral atoms: atomic messengers from our heliosphere’s edge
Of IMAP’s 10 instruments, three will investigate the boundaries of the heliosphere by collecting energetic neutral atoms, or ENAs. Many ENAs originate as positively charged particles released by the Sun but after racing across the solar system, these particles run into particles in interstellar space. In this collision, some of those positively charged particles become neutral, and an energetic neutral atom is born. The interaction also redirects the new ENAs, and some ricochet back toward the Sun.
Charged particles are forced to follow magnetic field lines, but ENAs travel in a straight line, unaffected by the twists, turns, and turbulences in the magnetic fields that permeate space and shape the boundary of the heliosphere. This means scientists can track where these atomic messengers came from and study distant regions of space from afar. The IMAP mission will use the ENAs it collects near Earth to trace back their origins and construct maps of the boundaries of the heliosphere, which would otherwise be invisible from such a distance.
“With its comprehensive state-of-the-art suite of instruments, IMAP will advance our understanding of two fundamental questions of how particles are energized and transported throughout the heliosphere and how the heliosphere itself interacts with our galaxy,” said Shri Kanekal, IMAP mission scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland.
The IMAP mission will study the heliosphere, our home in space. NASA/Princeton University/Patrick McPike Space weather: monitoring solar wind
The IMAP mission will also support near real-time observations of the solar wind and energetic solar particles, which can produce hazardous conditions in the space environment near Earth. From its location at Lagrange Point 1, about 1 million miles from Earth toward the Sun, IMAP will provide around a half hour’s warning of dangerous particles headed toward our planet. The mission’s data will help with the development of models that can predict the impacts of space weather ranging from power-line disruptions to loss of satellites.
“The IMAP mission will provide very important information for deep space travel, where astronauts will be directly exposed to the dangers of the solar wind,” said David McComas, IMAP principal investigator at Princeton University.
Cosmic dust: hints of the galaxy beyond
In addition to measuring ENAs and solar wind particles, IMAP will also make direct measurements of interstellar dust — clumps of particles originating outside of the solar system that are smaller than a grain of sand. This space dust is largely composed of rocky or carbon-rich grains leftover from the aftermath of supernova explosions.
The specific elemental composition of this space dust is a postmark for where it comes from in the galaxy. Studying cosmic dust can provide insight into the compositions of stars from far outside our solar system. It will also help scientists significantly advance what we know about these basic cosmic building materials and provide information on what the material between stars is made of.
David McComas leads the mission with an international team of 27 partner institutions. APL is managing the development phase and building the spacecraft, and it will operate the mission. IMAP is the fifth mission in NASA’s Solar Terrestrial Probes Program portfolio. The Explorers and Heliophysics Projects Division at NASA Goddard manages the STP Program for the agency’s Heliophysics Division of NASA’s Science Mission Directorate. NASA’s Launch Services Program, based at NASA’s Kennedy Space Center in Florida, manages the launch service for the mission.
By Mara Johnson-Groh
NASA’s Goddard Space Flight Center, Greenbelt, Md.
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Last Updated Sep 17, 2025 Related Terms
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By NASA
6 min read
Preparations for Next Moonwalk Simulations Underway (and Underwater)
This artist’s concept shows a brown dwarf — an object larger than a planet but not massive enough to kickstart fusion in its core like a star. Brown dwarfs are hot when they form and may glow like this one, but over time they get closer in temperature to gas giant planets like Jupiter. NOIRLab/NSF/AURA/R. Proctor An unusual cosmic object is helping scientists better understand the chemistry hidden deep in Jupiter and Saturn’s atmospheres — and potentially those of exoplanets.
Why has silicon, one of the most common elements in the universe, gone largely undetected in the atmospheres of Jupiter, Saturn, and gas planets like them orbiting other stars? A new study using observations from NASA’s James Webb Space Telescope sheds light on this question by focusing on a peculiar object that astronomers discovered by chance in 2020 and called “The Accident.”
The results were published on Sept. 4 in the journal Nature.
As shown in this graphic, brown dwarfs can be far more massive than even large gas planets like Jupiter and Saturn. However, they tend to lack the mass that kickstarts nuclear fusion in the cores of stars, causing them to shine. NASA/JPL-Caltech The Accident is a brown dwarf, a ball of gas that’s not quite a planet and not quite a star. Even among its already hard-to-classify peers, The Accident has a perplexing mix of physical features, some of which have been previously seen in only young brown dwarfs and others seen only in ancient ones. Because of those features, it slipped past typical detection methods before being discovered five years ago by a citizen scientist participating in Backyard Worlds: Planet 9. The program lets people around the globe look for new discoveries in data from NASA’s now-retired NEOWISE (Near-Earth Object Wide-field Infrared Survey Explorer), which was managed by NASA’s Jet Propulsion Laboratory in Southern California.
The brown dwarf nicknamed “The Accident” can be seen moving in the bottom left corner of this video, which shows data from NASA’s now-retired NEOWISE (Near-Earth Object Wide-Field Infrared Survey Explorer), launched in 2009 with the moniker WISE. NASA/JPL-Caltech/Dan Caselden The Accident is so faint and odd that researchers needed NASA’s most powerful space observatory, Webb, to study its atmosphere. Among several surprises, they found evidence of a molecule they couldn’t initially identify. It turned out to be a simple silicon molecule called silane (SiH4). Researchers have long expected — but been unable — to find silane not only in our solar system’s gas giants, but also in the thousands of atmospheres belonging to brown dwarfs and to the gas giants orbiting other stars. The Accident is the first such object where this molecule has been identified.
Scientists are fairly confident that silicon exists in Jupiter and Saturn’s atmospheres but that it is hidden. Bound to oxygen, silicon forms oxides such as quartz that can seed clouds on hot gas giants, bearing a resemblance to dust storms on Earth. On cooler gas giants like Jupiter and Saturn, these types of clouds would sink far beneath lighter layers of water vapor and ammonia clouds, until any silicon-containing molecules are deep in the atmosphere, invisible even to the spacecraft that have studied those two planets up close.
Some researchers have also posited that lighter molecules of silicon, like silane, should be found higher up in these atmospheric layers, left behind like traces of flour on a baker’s table. That such molecules haven’t appeared anywhere except in a single, peculiar brown dwarf suggests something about the chemistry occurring in these environments.
“Sometimes it’s the extreme objects that help us understand what’s happening in the average ones,” said Faherty, a researcher at the American Museum of Natural History in New York City, and lead author on the new study.
Happy accident
Located about 50 light-years from Earth, The Accident likely formed 10 billion to 12 billion years ago, making it one of the oldest brown dwarfs ever discovered. The universe is about 14 billion years old, and at the time that The Accident developed, the cosmos contained mostly hydrogen and helium, with trace amounts of other elements, including silicon. Over eons, elements like carbon, nitrogen, and oxygen forged in the cores of stars, so planets and stars that formed more recently possess more of those elements.
Webb’s observations of The Accident confirm that silane can form in brown dwarf and planetary atmospheres. The fact that silane seems to be missing in other brown dwarfs and gas giant planets suggests that when oxygen is available, it bonds with silicon at such a high rate and so easily, virtually no silicon is left over to bond with hydrogen and form silane.
So why is silane in The Accident? The study authors surmise it is because far less oxygen was present in the universe when the ancient brown dwarf formed, resulting in less oxygen in its atmosphere to gobble up all the silicon. The available silicon would have bonded with hydrogen instead, resulting in silane.
“We weren’t looking to solve a mystery about Jupiter and Saturn with these observations,” said JPL’s Peter Eisenhardt, project scientist for the WISE (Wide-field Infrared Survey Explorer) mission, which was later repurposed as NEOWISE. “A brown dwarf is a ball of gas like a star, but without an internal fusion reactor, it gets cooler and cooler, with an atmosphere like that of gas giant planets. We wanted to see why this brown dwarf is so odd, but we weren’t expecting silane. The universe continues to surprise us.”
Brown dwarfs are often easier to study than gas giant exoplanets because the light from a faraway planet is typically drowned out by the star it orbits, while brown dwarfs generally fly solo. And the lessons learned from these objects extend to all kinds of planets, including ones outside our solar system that might feature potential signs of habitability.
“To be clear, we’re not finding life on brown dwarfs,” said Faherty. “But at a high level, by studying all of this variety and complexity in planetary atmospheres, we’re setting up the scientists who are one day going to have to do this kind of chemical analysis for rocky, potentially Earth-like planets. It might not specifically involve silicon, but they’re going to get data that is complicated and confusing and doesn’t fit their models, just like we are. They’ll have to parse all those complexities if they want to answer those big questions.”
More about WISE, Webb
A division of Caltech, JPL managed and operated WISE for NASA’s Science Mission Directorate. The mission was selected competitively under NASA’s Explorers Program managed by the agency’s Goddard Space Flight Center in Greenbelt, Maryland. The NEOWISE mission was a project of JPL and the University of Arizona in Tucson, supported by NASA’s Planetary Defense Coordination Office.
For more information about WISE, go to:
https://www.nasa.gov/mission_pages/WISE/main/index.html
The James Webb Space Telescope is the world’s premier space science observatory, and an international program led by NASA with its partners, ESA (European Space Agency) and CSA (Canadian Space Agency).
To learn more about Webb, visit:
https://science.nasa.gov/webb
News Media Contacts
Calla Cofield
Jet Propulsion Laboratory, Pasadena, Calif.
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Christine Pulliam
Space Telescope Science Institute, Baltimore, Md.
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Last Updated Sep 09, 2025 Related Terms
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6 Min Read Upcoming Launch to Boost NASA’s Study of Sun’s Influence Across Space
Soon, there will be three new ways to study the Sun’s influence across the solar system with the launch of a trio of NASA and National Oceanic and Atmospheric Administration (NOAA) spacecraft. Expected to launch no earlier than Tuesday, Sept. 23, the missions include NASA’s IMAP (Interstellar Mapping and Acceleration Probe), NASA’s Carruthers Geocorona Observatory, and NOAA’s SWFO-L1 (Space Weather Follow On-Lagrange 1) spacecraft.
The three missions will launch together aboard a SpaceX Falcon 9 rocket from NASA’s Kennedy Space Center in Florida. From there, the spacecraft will travel together to their destination at the first Earth-Sun Lagrange point (L1), around one million miles from Earth toward the Sun.
The missions will each focus on different effects of the solar wind — the continuous stream of particles emitted by the Sun — and space weather — the changing conditions in space driven by the Sun — from their origins at the Sun to their farthest reaches billions of miles away at the edge of our solar system. Research and observations from the missions will help us better understand the Sun’s influence on Earth’s habitability, map our home in space, and protect satellites and voyaging astronauts and airline crews from space weather impacts.
The IMAP and Carruthers missions add to NASA’s heliophysics fleet of spacecraft. Together, NASA’s heliophysics missions study a vast, interconnected system from the Sun to the space surrounding Earth and other planets to the farthest limits of the Sun’s constantly flowing streams of solar wind. The SWFO-L1 mission, funded and operated by NOAA, will be the agency’s first satellite designed specifically for and fully dedicated to continuous, operational space weather observations.
Mapping our home in space: IMAP
The IMAP mission will study the heliosphere, our home in space.
NASA/Princeton University/Patrick McPike As a modern-day celestial cartographer, IMAP will investigate two of the most important overarching issues in heliophysics: the interaction of the solar wind at its boundary with interstellar space and the energization of charged particles from the Sun.
The IMAP mission will principally study the boundary of our heliosphere — a huge bubble created by the solar wind that encapsulates our solar system — and study how the heliosphere interacts with the local galactic neighborhood beyond. The heliosphere protects the solar system from dangerous high-energy particles called galactic cosmic rays. Mapping the heliosphere’s boundaries helps scientists understand our home in space and how it came to be habitable.
“IMAP will revolutionize our understanding of the outer heliosphere,” said David McComas, IMAP mission principal investigator at Princeton University in New Jersey. “It will give us a very fine picture of what’s going on out there by making measurements that are 30 times more sensitive and at higher resolution than ever before.”
The IMAP mission will also explore and chart the vast range of particles in interplanetary space. The spacecraft will provide near real-time observations of the solar wind and energetic particles, which can produce hazardous conditions not only in the space environment near Earth, but also on the ground. The mission’s data will help model and improve prediction capabilities of the impacts of space weather ranging from power-line disruptions to loss of satellites.
Imaging Earth’s exosphere: Carruthers Geocorona Observatory
An illustration shows the Carruthers Geocorona Observatory spacecraft. NASA/BAE Systems Space & Mission Systems The Carruthers Geocorona Observatory, a small satellite, will launch with IMAP as a rideshare. The mission was named after Dr. George Carruthers, creator of the Moon-based telescope that captured the first images of Earth’s exosphere, the outermost layer of our planet’s atmosphere.
The Carruthers mission will build upon Dr. Carruthers’ legacy by charting changes in Earth’s exosphere. The mission’s vantage point at L1 offers a complete view of the exosphere not visible from the Moon’s relatively close distance to Earth. From there, it will address fundamental questions about the nature of the region, such as its shape, size, density, and how it changes over time.
The exosphere plays an important role in Earth’s response to space weather, which can impact our technology, from satellites in orbit to communications signals in the upper atmosphere or power lines on the ground. During space weather storms, the exosphere mediates the energy absorption and release throughout the near-Earth space environment, influencing strength of space weather disturbances. Carruthers will help us better understand the fundamental physics of our exosphere and improve our ability to predict the impacts of the Sun’s activity.
“We’ll be able to create movies of how this atmospheric layer responds when a solar storm hits, and watch it change with the seasons over time,” said Lara Waldrop, the principal investigator for the Carruthers Geocorona Observatory at the University of Illinois at Urbana-Champaign.
New space weather station: SWFO-L1
SWFO-L1 will provide real-time observations of the Sun’s corona and solar wind to help forecast the resulting space weather.
NOAA/BAE Systems Space & Mission Systems Distinct from NASA’s research satellites, SWFO-L1 will be an operational satellite, designed to observe solar activity and the solar wind in real time to provide critical data in NOAA’s mission to protect the nation from environmental hazards. SWFO-L1 will serve as an early-warning beacon for potentially damaging space weather events that could impact our technology on Earth. SWFO-L1 will observe the Sun’s outer atmosphere for large eruptions, called coronal mass ejections, and measure the solar wind upstream from Earth with a state-of-the-art suite of instruments and processing system.
This mission is the first of a new generation of NOAA space weather observatories dedicated to 24/7 operations, working to avoid gaps in continuity.
“SWFO-L1 will be an amazing deep-space mission for NOAA,” said Dimitrios Vassiliadis, SWFO program scientist at NOAA. “Thanks to its advantageous location at L1, it will continuously monitor the solar atmosphere while measuring the solar wind and its interplanetary magnetic fields well before it impacts Earth — and transmit these data in record time.”
With SWFO-L1’s enhanced performance, unobstructed views, and minimal delay between observations and data return, NOAA’s Space Weather Prediction Center forecasters will give operators improved lead time required to take precautionary actions that protect vital infrastructure, economic interests, and national security on Earth and in space.
By Mara Johnson-Groh
NASA’s Goddard Space Flight Center, Greenbelt, Md.
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Last Updated Sep 04, 2025 Related Terms
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By NASA
A member of the space crop production team prepares materials for Veggie seed pillows inside the Space Systems Processing Facility at NASA’s Kennedy Space Center. NASA/Cory S Huston When the Crew-11 astronauts launched to the International Space Station on August 1, 2025, they carried with them another chapter in space farming: the latest VEG-03 experiments, complete with seed pillows ready for planting.
Growing plants provides nutrition for astronauts, as well as psychological benefits that help maintain crew morale during missions.
During VEG-03 MNO, astronauts will be able to choose what they want to grow from a seed library including Wasabi mustard greens, Red Russian Kale, and Dragoon lettuce.
From Seed to Space Salad
The experiment takes place inside Veggie, a chamber about the size of carry-on luggage. The system uses red, blue, and green LED lights to provide the right spectrum for plant growth. Clear flexible bellows — accordion-like walls that expand to accommodate maturing plants — create a semi-controlled environment around the growing area.
Astronauts plant thin strips containing their selected seeds into fabric “seed pillows” filled with a special clay-based growing medium and controlled-release fertilizer. The clay, similar to what’s used on baseball fields, helps distribute water and air around the roots in the microgravity environment.
Crew members will monitor the plants, add water as needed, and document growth through regular photographs. At harvest time, astronauts will eat some of the fresh produce while freezing other samples for return to Earth, where scientists will analyze their nutritional content and safety.
How this benefits space exploration
Fresh food will become critical as astronauts venture farther from Earth on missions to the Moon and Mars. NASA aims to validate different kinds of crops to add variety to astronaut diets during long-duration space exploration missions, while giving crew members more control over what they grow and eat.
How this benefits humanity
The techniques developed for growing crops in space’s challenging conditions may also improve agricultural practices on Earth. Indoor crop cultivation approaches similar to what astronauts do in Veggie might also be adapted for horticultural therapy programs, giving elderly or disabled individuals new ways to experience gardening when traditional methods aren’t accessible.
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About BPS
NASA’s Biological and Physical Sciences Division pioneers scientific discovery and enables exploration by using space environments to conduct investigations not possible on Earth. Studying biological and physical phenomenon under extreme conditions allows researchers to advance the fundamental scientific knowledge required to go farther and stay longer in space, while also benefitting life on Earth.
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By NASA
Explore Hubble Science Hubble Space Telescope As NASA Missions Study… Hubble Home Overview About Hubble The History of Hubble Hubble Timeline Why Have a Telescope in Space? Hubble by the Numbers At the Museum FAQs Impact & Benefits Hubble’s Impact & Benefits Science Impacts Cultural Impact Technology Benefits Impact on Human Spaceflight Astro Community Impacts Science Hubble Science Science Themes Science Highlights Science Behind Discoveries Hubble’s Partners in Science Universe Uncovered AI and Hubble Science Explore the Night Sky Observatory Hubble Observatory Hubble Design Mission Operations Missions to Hubble Hubble vs Webb Team Hubble Team Career Aspirations Hubble Astronauts Multimedia Images Videos Sonifications Podcasts e-Books Online Activities 3D Hubble Models Lithographs Fact Sheets Posters Hubble on the NASA App Glossary News Hubble News Social Media Media Resources More 35th Anniversary Online Activities 4 min read
As NASA Missions Study Interstellar Comet, Hubble Makes Size Estimate
Hubble captured this image of the interstellar comet 3I/ATLAS on July 21, 2025, when the comet was 277 million miles from Earth. Hubble shows that the comet has a teardrop-shaped cocoon of dust coming off its solid, icy nucleus. Image: NASA, ESA, David Jewitt (UCLA); Image Processing: Joseph DePasquale (STScI) A team of astronomers has taken the sharpest-ever picture of the unexpected interstellar comet 3I/ATLAS using the crisp vision of NASA’s Hubble Space Telescope. Hubble is one of many missions across NASA’s fleet of space telescopes slated to observe this comet, together providing more information about its size and physical properties. While the comet poses no threat to Earth, NASA’s space telescopes help support the agency’s ongoing mission to find, track, and better understand near-Earth objects.
Hubble’s observations allow astronomers to more accurately estimate the size of the comet’s solid, icy nucleus. The upper limit on the diameter of the nucleus is 3.5 miles (5.6 kilometers), though it could be as small as 1,000 feet (320 meters) across, researchers report. Though the Hubble images put tighter constraints on the size of the nucleus compared to previous ground-based estimates, the solid heart of the comet presently cannot be directly seen, even by Hubble. Observations from other NASA missions including the James Webb Space Telescope, TESS (Transiting Exoplanet Survey Satellite), and the Neil Gehrels Swift Observatory, as well as NASA’s partnership with the W.M. Keck Observatory, will help further refine our knowledge about the comet, including its chemical makeup.
Hubble also captured a dust plume ejected from the Sun-warmed side of the comet, and the hint of a dust tail streaming away from the nucleus. Hubble’s data yields a dust-loss rate consistent with comets that are first detected around 300 million miles from the Sun. This behavior is much like the signature of previously seen Sun-bound comets originating within our solar system.
The big difference is that this interstellar visitor originated in some other solar system elsewhere in our Milky Way galaxy.
3I/ATLAS is traveling through our solar system at a staggering 130,000 miles (209,000 kilometers) per hour, the highest velocity ever recorded for a solar system visitor. This breathtaking sprint is evidence that the comet has been drifting through interstellar space for many billions of years. The gravitational slingshot effect from innumerable stars and nebulae the comet passed added momentum, ratcheting up its speed. The longer 3I/ATLAS was out in space, the higher its speed grew.
“No one knows where the comet came from. It’s like glimpsing a rifle bullet for a thousandth of a second. You can’t project that back with any accuracy to figure out where it started on its path,” said David Jewitt of the University of California, Los Angeles, science team leader for the Hubble observations.
The paper will be published in The Astrophysical Journal Letters. It is already available on Astro-ph.
New Evidence for Population of Wandering Space Relics
“This latest interstellar tourist is one of a previously undetected population of objects bursting onto the scene that will gradually emerge,” said Jewitt. “This is now possible because we have powerful sky survey capabilities that we didn’t have before. We’ve crossed a threshold.”
This comet was discovered by the NASA-funded Asteroid Terrestrial-impact Last Alert System (ATLAS) on July 1, 2025, at a distance of 420 million miles from the Sun. ATLAS is an asteroid impact early warning system developed by the University of Hawai’i.
In the meantime, other NASA missions will provide new insight into this third interstellar interloper, helping refine our understanding of these objects for the benefit of all. 3I/ATLAS should remain visible to ground-based telescopes through September, after which it will pass too close to the Sun to observe, and is expected to reappear on the other side of the Sun by early December.
The Hubble Space Telescope has been operating for more than three decades and continues to make ground-breaking discoveries that shape our fundamental understanding of the universe. Hubble is a project of international cooperation between NASA and ESA (European Space Agency). NASA’s Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope and mission operations. Lockheed Martin Space, based in Denver, also supports mission operations at Goddard. The Space Telescope Science Institute in Baltimore, which is operated by the Association of Universities for Research in Astronomy, conducts Hubble science operations for NASA.
To learn more about Hubble, visit: https://science.nasa.gov/hubble
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Comet 3I/ATLAS
Hubble captured this image of the interstellar comet 3I/ATLAS on July 21, 2025, when the comet was 277 million miles from Earth. Hubble shows that the comet has a teardrop-shaped cocoon of dust coming off its solid, icy nucleus.
Comet 3I/ATLAS Compass Image
This image of interstellar comet 3I/ATLAS was captured by the Hubble Space Telescope’s Wide Field Camera on July 21, 2025. The scale bar is labeled in arcseconds, which is a measure of angular distance on the sky. One arcsecond is equal an angular measurement of 1/3600 of o…
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Last Updated Aug 07, 2025 Editor Andrea Gianopoulos Location NASA Goddard Space Flight Center Contact Media Claire Andreoli
NASA’s Goddard Space Flight Center
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Ray Villard
Space Telescope Science Institute
Baltimore, Maryland
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Science Paper: Hubble Space Telescope Observations of the Interstellar Interloper 3I/ATLAS, PDF (1.57 MB)
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