The estimated diameter of the nucleus of comet C/2014 UN271 (Bernardinelli-Bernstein) is approximately 137 km (85 miles) across, making it the largest nucleus ever seen in a comet by astronomers. The previous record holder is comet C/2002 VQ94, with a nucleus estimated to be 100 km (60 miles) across. This image, taken by Hubble’s Wide Field Camera 3 on January 8, 2022, shows comet C/2014 UN271 (Bernardinelli-Bernstein). Image credit: NASA / ESA...
