Attention Authors: Updated Practice for Review Articles and Position Papers in arXiv CS Category – arXiv blog

Rapid Brightening of 3I/ATLAS Ahead of Perihelion

Interstellar comet 3I/ATLAS has been approaching its 2025 October 29 perihelion while opposite the Sun from Earth, hindering ground-based optical observations over the preceding month. However, this geometry placed the comet within the fields of view of several space-based solar coronagraphs and heliospheric imagers, enabling its continued observation during its final approach toward perihelion. We report photometry from STEREO-A's SECCHI HI1 and COR2, SOHO's LASCO C3, and GOES-19's CCOR-1 instruments in 2025 September--October, which show a rapid rise in the comet's brightness scaling with heliocentric distance r as r^(-7.5+/-1.0). CCOR-1 also resolves the comet as an extended source with an apparent coma ~4' in diameter. Furthermore, LASCO color photometry shows the comet to be distinctly bluer than the Sun, consistent with gas emission contributing a substantial fraction of the visible brightness near perihelion.

AI is not popular, and AI users are unpleasant asshats

Some AI papers have a finding so good you just want to quote it everywhere. But many turn out to be trash. They’ve got bad statistics, they’ve got bad methodology, they’re really sales pieces, or t…