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View Interstellar Comet 3I/ATLAS Through NASA’s Multiple Lenses
This article was updated to include the full range of dates from the SOHO image.
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NASA is in the midst of an unprecedented solar system-wide observation campaign, turning its spacecraft and space telescopes to follow comet 3I/ATLAS, the third known interstellar object to pass through our solar system. Twelve NASA assets have captured and processed imagery of the comet since it was first discovered on July 1, and several others will have opportunities to capture more images as the comet continues to pass through our solar system.
By observing the comet from so many locations, NASA has an opportunity to learn about the ways that 3I/ATLAS differs from our solar system’s home-grown comets and give scientists a new window into how the compositions of other systems may differ from our own.
Observations from Mars
The closest imagery of the comet was taken by NASA’s spacecraft at Mars. Earlier this fall, 3I/ATLAS passed by Mars from a distance of 19 million miles, where it was observed by three NASA spacecraft. The Mars Reconnaissance Orbiter (MRO) captured one of the closest images of the comet, while the MAVEN (Mars Atmosphere and Volatile EvolutioN) orbiter obtained ultraviolet images that will help scientists understand the comet’s make-up. Meanwhile, the Perseverance rover grabbed a faint glimpse from the surface of Mars.
NASA’s Mars Reconnaissance MissionThe High Resolution Imaging Science Experiment (HiRISE) camera aboard NASA’s Mars Reconnaissance Orbiter captured this image of interstellar comet 3I/ATLAS on Oct. 2, 2025. At the time it was imaged, the comet was about 0.2 astronomical units (19 million miles, or 30 million kilometers) from the spacecraft.NASA/JPL-Caltech/University of Arizona
NASA’s MAVEN MissionAn ultraviolet image composite of the hydrogen atoms surrounding comet 3I/ATLAS, the third interstellar object ever detected by astronomers, as it passes through our solar system. This image was taken on Sept 28, 2025- just days before the comet’s closest approach to Mars – by an instrument on NASA’s MAVEN spacecraft, which has been studying Mars from orbit since 2014. The instrument, the Imaging Ultraviolet Spectrograph, takes pictures in the ultraviolet part of the spectrum to reveal the chemical composition of objects. The image shows hydrogen emitted from different sources: the comet (dim spot on the far left), hydrogen from Mars (bright emission on the right), and hydrogen flowing through our solar system between the planets (dim emission in the middle). MAVEN’s spectrograph distinguished the comet’s hydrogen from the interplanetary and Martian hydrogen using a special mode to separate each source by its speed. Hydrogen emission from the comet is confined to the location of the comet on the sky, which is why it is small and round instead of extended.NASA/Goddard/LASP/CU Boulder
NASA’s Perseverance MissionInterstellar comet 3I/ATLAS is seen as a faint smudge against a background starfield in two images taken by the Mastcam-Z instrument aboard NASA’s Perseverance Mars rover on Oct. 4, 2025. At the time it was imaged, the comet was about 18.6 million miles (29.9 million kilometers) from the rover, which was exploring the rim of the Red Planet’s Jezero Crater.NASA/JPL-Caltech/ASU/MSSS
Sun watchers’ view
Some of NASA’s heliophysics missions have the unique ability to observe areas of the sky near the Sun, which allowed them to track comet 3I/ATLAS as it passed behind our Sun as seen from Earth, making observations with ground-based telescopes impossible. NASA’s STEREO (Solar Terrestrial Relations Observatory) captured images from Sept. 11 to Oct. 2, and the ESA (European Space Agency) and NASA mission SOHO (Solar and Heliospheric Observatory) observed the comet from Oct. 15 to 26. Images from NASA’s PUNCH (Polarimeter to Unify the Corona and Heliosphere) mission, which launched earlier this year, reveal the comet’s tail during observations from Sept. 20 to Oct. 3.
Despite previously observing and discovering thousands of comets, this is the first time NASA’s heliophysics missions have purposefully observed an object originating in another solar system.
NASA’s STEREO MissionThis video shows the 3I/ATLAS interstellar comet as a bright, fuzzy orb in the center. Traveling through our solar system at a staggering 130,000 miles (209,000 kilometers) per hour, 3I/ATLAS was made visible by using a series of stacked images from Sept. 11-25, using the Heliocentric Imager-1 (HI1) instrument, a visible-light imager on the STEREO-A (Solar Terrestrial Relations Observatory) spacecraft. Originally, the comet was expected to be too faint to be observed, but the comet brightened up enough to be visible, allowing the HI1 instrument to see the comet against a noise-dominated background through a combination of frames.NASA/Lowell Observatory/Qicheng Zhang
ESA/NASA’s SOHO Mission A faint image of comet 3I/ATLAS as observed by ESA/NASA’s SOHO mission between Oct. 15-16, 2025. The comet appears as a slight brightening in the center of the image.Lowell Observatory/Qicheng Zhang
NASA’s PUNCH MissionComet 3I/ATLAS appears as a bright object near the center of this image, made from combining observations from NASA’s PUNCH mission taken from Sept. 20 to Oct. 3, 2025, when the comet was about 231 million to 235 million miles from Earth. Its tail appears as a short elongation to the right. Stars appear as streaks in the background. NASA/Southwest Research Institute
Asteroid explorers
NASA’s Psyche and Lucy spacecraft, currently on their respective outbound journeys to study various asteroid targets throughout the solar system, were able to observe 3I/ATLAS en route. On Sept. 8 and 9, Psyche acquired four observations of the comet over eight hours from a distance of 33 million miles. These images will help scientists refine the comet’s trajectory. On Sept. 16, Lucy took a series of images from 240 million miles away. Stacking these images together provides detail on the comet’s coma and tail.
NASA’s Psyche MissionNASA’s Psyche mission acquired four observations of interstellar comet 3I/ATLAS over the course of eight hours on Sept. 8 and 9, 2025, when the comet was about 33 million miles (53 million kilometers) from the spacecraft. The data, captured by Psyche’s multispectral imager, is helping astronomers both refine the trajectory of 3I/ATLAS and learn more about the faint coma, or cloud of gas, surrounding its nucleus (shown in the zoomed-in inset image).NASA/JPL-Caltech/ASU
NASA’s Lucy MissionThe interstellar comet 3I/ATLAS, circled in the center, as seen by the L’LORRI panchromatic, or black-and-white, imager on NASA’s Lucy spacecraft. This image was made by stacking a series of images taken on Sept. 16, 2025, as the comet was zooming toward Mars. Lucy was 240 million miles away from 3I/ATLAS at the time making its way to explore eight asteroids that share an orbit with Jupiter. The L’LORRI imager captured the comet’s coma, the fuzzy halo of gas and dust surrounding 3I/ATLAS above, and its tail, a smudge of gas flowing to the right of the comet. This image spans about 11 arcminutes of sky, or roughly one-third the width of the full Moon. Solar system north is up.NASA/Goddard/SwRI/JHU-APL
The NASA-funded ATLAS (Asteroid Terrestrial-impact Last Alert System) telescope in Chile discovered 3I/ATLAS on July 1. Later that month it was viewed by NASA’s Hubble Space Telescope. In August, both NASA’s James Webb Telescope and SPHEREx (Spectro-Photometer for the History of the Universe, Epoch of Reionization and Ices Explorer) captured imagery.
Comet 3I/ATLAS will fly closest to Earth about Friday, Dec. 19, at 170 million miles, which is almost twice the distance between the Earth and Sun. NASA spacecraft will continue to observe the comet as it makes its journey through the solar system, passing the orbit of Jupiter in spring 2026.
For more information on NASA’s comet 3I/ATLAS observations, visit:
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