Comets can be one of the most amazing sights in the heavens, with bright, naked-eye comas and tails stretching across half the sky. The most spectacular comet appearances are called "great" comets, but such an occurrence is infrequent enough that it is also nicknamed a "comet of the century." In preparation for the Thanksgiving Day perihelion passage of comet ISON, along with its great possibilities, it's a proper time to examine the humble origins, from the most rural parts of the solar system, of these briefly blazing celestial visitors.
The speaker is Dr. Frank Summers of the Space Telescope Science Institute. The video was recorded at the Space Telescope Science Institute in Baltimore, Maryland, on 11 November 2013.