Western Kentucky University

Comet ISON

 

Comets: Icy Interlopers Interacting with the Sun


Comet ISON was a 3-mile wide chunk of dirty ice. Decades ago it was orbiting the Sun in the remotest boondocks of the solar system, well beyond Neptune and Pluto, when some other object passed near and gravity nudged comet ISON into a new orbit moving toward the Sun. Thawing as it approaches the Sun, this frozen interloper shedded hundreds of thousands of pounds of dust and gas every minute. Ejected material stretched behind the orbit and reflected sunlight, creating the comet's tail.


Just a few comets in the last generation have developed exceptionally long tails stretching across the sky. On Thanksgiving Day, 28 November 2013, comet ISON was moving over 225,000 mph as its orbit took it within a million miles above the Sun's incandescent surface. A few days later, when it moved enough away from the Sun to be viewed from Kentucky, comet ISON could have been spectacular to behold. Unfortunately, ISON was disrupted as it passed within 1,100,000 miles of the Sun (barely one Sun diameter), and broke apart.  Disruption is the fate of many "sungrazing" comets.

 



(Hardin Planetarium performed at show about Comets from Dec. 1 to Dec. 22nd, 2013, inspired by the appearance of Comet ISON in our Solar System).

 Last Modified 1/2/14