New studies of the interstellar comet 3I/ATLAS show that it's a lot smaller than indicated by early estimates, which were really upper limits. Our interstellar visitor is no more than 5.6 km (3.5 miles) wide, probably less.

Which makes sense--small objects are a lot more common than big ones.

https://arxiv.org/abs/2508.02934 #space #science #nature