If you've ever attended a star party where amateur astronomers set up telescopes to peruse stars and nebulae, you'll come away with a notion that the heavens look pretty sedate.
But an amateur astronomer wound up looking at the right place at the right time to capture the breakup of a comet. The International Astronomical Union have even called the observation a "major astronomical discovery."
British amateur Nick Howes took pictures on March 18th and 19th showing the icy nucleus of comet C2007 C3 splitting on its outward leg form the sun.
Working from his desktop computer in Great Britain, Nick dialed up the comet's coordinates, set exposure, and captured a set of six pictures that showed an object moving away from the main nucleus. He used a remote-controlled 2-meter telescope located half a world away in Hawaii and operated by the Faulkes Telescope Project.
Apparently a mountain-sized chunk of ice broke away from the central nucleus and became a flying iceberg. Follow-up images taken a day later showed the new fragment trailing ever farther from the comet core.
Comet fragmentation is an ongoing fireworks show in the solar system. It tells us comets are a very loose agglomeration of smaller pieces.
The results support the popular theory that comet nuclei are really made up of a cluster of smaller icy bodies called "cometessimals." Since the 1950s, comet nuclei have been commonly assumed to be loose mixture of ice and dust - "dirty snowballs" weakly held together by gravity. Solar heat causes the ices to sublimate and violently release gas as explosions and garden-hose style jets, and the pressure of the solar radiation pressure blows away particles like debris caught in a gale.