Europa Clipper Observed 3I/ATLAS Near Perihelion
NASA’s Europa Clipper spacecraft observed the interstellar object 3I/ATLAS on November 6, 2025, from a distance of 164 million kilometers. During an observing period of seven hours, the Europa Ultraviolet Spectrograph (UVS) instrument recorded data on the abundances of various elements in the gas plume surrounding the nucleus of 3I/ATLAS.
A false-color image was obtained by stacking the brightness maps at multiple UV wavelengths. The image is extremely valuable in constraining the anti-tail and tail geometry of 3I/ATLAS near perihelion. Europa Clipper observed 3I/ATLAS when Earth-based observations were largely blocked by the Sun’s position.
With 3I/ATLAS passing between Europa Clipper and the Sun, the vantage point of Clipper’s observations provided a unique perspective. The sunward viewpoint provided a downstream view of the anti-tail and tail stemming out of the nucleus of 3I/ATLAS when it went close to the Sun.
Europa-UVS detected the spectral fingerprints of oxygen, hydrogen and dust from the outgassing of 3I/ATLAS near perihelion.
Europa Clipper was launched from Earth in October 2024, and is expected to arrive near Jupiter in April 2030, where it will study Jupiter’s frozen moon Europa — inside of which a subsurface liquid ocean might support life. Clipper will orbit Jupiter and perform 49 close flybys of Europa.
Following the rendezvous with Europa Clipper, 3I/ATLAS will arrive closest to Jupiter as early as March 16, 2026, demonstrating how fast it is relative to a human-made spacecraft. In a TV interview today, I expressed my wish to board a fast interstellar traveler like 3I/ATLAS so that it would carry me out of the solar system faster than human-made spacecraft. Ad Astra!
ABOUT THE AUTHOR
Avi Loeb is the head of the Galileo Project, founding director of Harvard University’s — Black Hole Initiative, director of the Institute for Theory and Computation at the Harvard-Smithsonian Center for Astrophysics, and the former chair of the astronomy department at Harvard University (2011–2020). He is a former member of the President’s Council of Advisors on Science and Technology and a former chair of the Board on Physics and Astronomy of the National Academies. He is the bestselling author of “Extraterrestrial: The First Sign of Intelligent Life Beyond Earth” and a co-author of the textbook “Life in the Cosmos”, both published in 2021. The paperback edition of his new book, titled “Interstellar”, was published in August 2024.
