Largest comet ever observed was active at near-record distance

Astronomers show that comet Bernardinelli-Bernstein (BB), the largest comet ever discovered, was active long before previously thought, meaning the ice within it is vaporizing and forming an envelope of dust and vapor known as a coma. Only one active comet has been observed farther from the sun, and it was much smaller than comet BB.

from Latest Science News -- ScienceDaily https://ift.tt/3D6dgcT