Overview
- The closest approach occurred at 04:16 UTC on December 19 at a distance of 268,918,000 km, according to Russia’s Solar Astronomy Laboratory.
- Hubble, James Webb, JUICE and other facilities produced images and spectra showing an active coma with gases including carbon dioxide, carbon monoxide and water.
- ESA, NASA and many astronomers dismissed speculation of an artificial origin, describing 3I/ATLAS as a normal comet from another star.
- The comet’s hyperbolic trajectory means no return; a near-pass by Jupiter is expected around mid-March 2026 before it departs the Solar System.
- 3I/ATLAS was too faint for naked-eye viewing, so observers used telescopes and livestreams during predawn windows around the closest pass.