By Samuel Lopez | USA Herald – On October 29, 2025, as 3I/ATLAS reached perihelion at just under 203 million kilometers from the Sun, observatories on Earth had no direct line of sight. The object slipped behind the Sun, invisible to every telescope on the planet. But interstellar visitors do not wait for us to catch up, and a week later the ESA’s Jupiter Icy Moons Explorer—Juice—found itself unexpectedly close to the object.
ESA made a decision that will be studied for years to come: they pointed not one, but five scientific instruments at 3I/ATLAS during its flyby. A spacecraft built to study Europa, Ganymede, and Callisto suddenly became humanity’s first interplanetary witness to an interstellar anomaly racing through the inner system.
Those instruments collected data on the composition and shape of the gas and dust around 3I/ATLAS. But already the language is shifting. ESA describes the image as a “glowing halo of gas and dust,” yet nothing in the raw NavCam frame behaves like typical cometary emissions.
