Overview
- Tianwen-1’s newly released images from early October show 3I/ATLAS’s nucleus and expansive coma, marking a rare interstellar target captured by a Mars orbiter.
- High-resolution Mars Reconnaissance Orbiter images taken on October 2 remain withheld during the U.S. government shutdown, with NASA indicating they will be released once operations resume after a request from Rep. Anna Paulina Luna.
- Post-perihelion observations detect strong diatomic carbon emission that gives the comet a green appearance, while the seemingly missing dust tail is consistent with a near head-on viewing angle.
- JPL reports a small non-gravitational acceleration in the comet’s motion, and recent analyses estimate that it shed more than 13% of its mass around its late-October perihelion.
- Agencies affirm a safe closest Earth approach on December 19 at roughly 270 million kilometers as an international observing campaign intensifies, with most researchers assessing 3I/ATLAS as a natural interstellar comet despite public speculation.