Astrometric data suggests interstellar object 3I/ATLAS is anomalously large
The interstellar object 3I/ATLAS showed no measurable non-gravitational acceleration between May and September 2025, implying a nucleus mass above 33 billion tons and a diameter larger than 5 km (3 miles), according to a study co-authored by Harvard Professor Avi Loeb and published on September 24.
