Comet ISON—Bang or Bust?

Comet ISON has the potential to be spectacular — if it survives its Thanksgiving encounter with the sun.

After Dec. 3, starwatchers can call the re-activated Grinnell College Observatory hotline, 641-269-4770, to learn about viewing sessions.  The hotline will be updated once the fate of ISON — which enthusiasts say may be “the comet of the century” — becomes clearer.

Grinnell physics professor Bob Cadmus explains that Comet ISON is a new visitor to the inner solar system and is currently very pristine and bright — but its future is uncertain. “The comet will pass near the sun for the first time on Thanksgiving,” Cadmus says, “and we will learn more about its behavior after the pass-by occurs.”

According to a NASA Web site, the sun’s proximity may cause the icy comet to degrade and become less visible, or disappear completely. But if Comet ISON survives its trip around the sun, there’s a good chance, according to NASA, that it will be incredibly bright and easily visible with the naked eye in the northern hemisphere. In early December, it would be seen in the morning, low on the horizon to the east-southeast. In late December and early January, it will be visible all night long.

If the comet’s behavior warrants it, Cadmus says, the Grinnell College Observatory will host December viewing sessions in the pre-dawn hours. Telescopes will not be required; the comet should be visible with the naked eye. Cadmus will be on hand to provide information about the comet and other sights in the night sky.