Scientists spotted a giant comet spewing gas 2 billion miles from sun

A strange, city-sized comet seems to have woken up early as it drifts toward the sun — even though it's still much farther than Saturn in space.

Using a giant Chilean desert telescope, the Atacama Large Millimeter/submillimeter Array, scientists got a detailed look at C/2014 UN271. This comet, commonly known as Bernardinelli–Bernstein, is one of the largest and most distant ever detected, and it’s doing something no one saw coming. Despite being extremely far from the sun's heat in the freezing outskirts of the solar system...