The Panspermia theory holds that life first developed on these objects.
The Panspermia theory holds that life first developed on these objects. These objects contain a coma surrounding a nucleus. They originate in the Oort Cloud and Kuiper (KYE-per) Belt, and their dust tails point away from the Sun. They include Shoemaker-Levy 9, which crashed into Jupiter. For 10 points, name these "dirty snowballs," one of which passes by Earth every 76 years and was discovered by Edmond Halley.
The Panspermia theory holds that life first developed on these objects.
comets