Overview

• Hubble Space Telescope released its first high-resolution images on July 22, revealing a bright, well-developed gas and dust coma around 3I/ATLAS’s nucleus.
• A preprint study posted to arXiv the same day reports the coma contains about 30% water ice and 70% dust similar to the Tagish Lake meteorite.
• Vera C. Rubin Observatory data published July 21 estimate the comet’s nucleus measures roughly 5.6 kilometers in diameter.
• Harvard physicist Avi Loeb has suggested the object could be an alien probe based on its trajectory and size, while ESA’s Richard Moissl sees no evidence of nonnatural origins.
• Global teams are gearing up for close monitoring ahead of the comet’s October 29 perihelion and its closest Earth pass on December 17.