Comet 67P is obviously different from other comets visited so far. (sciencedaily.com)
Like other comets of its type, PANSTARRS is thought to have originated in the Oort Cloud, a vast region containing millions of comets located more than two light years from the Sun. (sciencedaily.com)
If other comets have oxygen, this glimpse into the early solar system's chemistry could help us piece together a record of conditions on early Earth, too. (newscientist.com)