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.
A little know visitor, Comet West, broke apart into four nuclei in August 1975 as it passed within 18 million miles of the sun. The problem was that the infamous comet Kohoutek made a lackluster appearance a couple year before. Some astronomers and news media had hyped it as possibly becoming the “comet of the century.” Therefore, comet West was largely ignored by news media.
The most infamous comet “daughter” particle was a piece seen following comet Hale-Bopp in 1997. It gained a following on the Internet as a suspected UFO “hiding” (not very well) in the tail of the bright sunward-bound comet.
“Illogical” as Mr. Spock would say. Why would stealthy aliens fly alongside the one celestial object that many professional and amateur telescopes were looking at? This UFO fairy tale regrettably inspired the Heavens Gate cult to commit mass suicide in the anticipation the UFO was going to pick them up.
This latest observation is encouraging for amateurs to use remote and powerful telescopes for more than sky watching. They can make new scientific discoveries that are appreciated and useful to professional astronomers to do follow-up research. The solar system is a dynamic and busy place full of transient phenomena such as comets and changes in the atmospheres of the giant planets. Professional telescopes can’t cover it all (at least not just yet). But amateur astronomers are a standing army of sky hunters that repeatedly come up with the most amazing discoveries.
Image: Comet C2007 C3 breaking up (top; credit: Nick Howes/Faulkes Telescope North).