The interstellar object 3I/ATLAS has entered a new observational phase after passing perihelion. Recent images reveal that the glowing halo surrounding the object has shifted in color — from red to green — prompting renewed scientific interest. In a recent article, Harvard astrophysicist Avi Loeb reviewed these observations and explained what the color change may reveal about the physical processes taking place around 3I/ATLAS.

Japan’s X-ray astronomy satellite XRISM, developed by JAXA in collaboration with NASA, has achieved a groundbreaking milestone:the world’s first X-ray detection from an interstellar object, 3I/ATLAS. Using its wide-field soft X-ray imager Xtend, XRISM captured a faint X-ray glow stretching nearly 400,000 kilometers from the object—an observation that opens a new window into the physics of interstellar bodies.

On November 19, 2025, NASA released several special feature articles on interstellar comet 3I/ATLAS in a single day. In total: five articles. Together, they describe a “solar system–wide tracking campaign” that mobilizes NASA’s full observational assets — from STEREO, SOHO, PUNCH, Lucy, and other spacecraft, to multiple planetary missions and deep-space observatories far from Earth. 3I/ATLAS is only the third interstellar comet ever observed in history. Once it leaves the