What powers a comet?
(MUSIC) Narrator: Welcome to Space Place Musings, a Podcast in which an expert answers questions from our Space Place museum and astronomy club partners across the nation. Im Diane Fisher, of the New Millennium Program. Our expert is Dr. Marc Rayman, a scientist at the Jet Propulsion Laboratory. Marc, our friends at the Back Bay Astronomy Club in Virginia Beach, Virginia, have a somewhat unusual question: What powers a comet? Rayman: Well, that’s an interesting way to look at comets. It does seem as if they must be under some kind of power like a rocket or a spacecraft with thrusters. Comets travel very fast, loop around the Sun, and have long tails. Narrator: But what is a comet made of? Rayman: A comet is a chunk of material left over from the formation of the solar system. About 4.6 billion years ago, our solar system formed from a vast cloud of gas and dust. More than 99% of the material in the cloud collected at the center and formed the Sun. Other big clumps of gas and dust becam
