Another Breakup: Comet Boethin forces Deep Impact to turn its eyes elsewhere

The holiday season is hard on everyone. There is the stress of trying to find the right gifts, trying to get the house ready for guests, trying to get finals graded, (trying to recover from the most malevolent case of the sniffles encountered in many years), and so many other stresses. It never surprises me to hear about breakups around the holidays, and NASA’s latest breakup news had plenty of foreshadowing.

That’s right, even though everything was a glow back in 1986, and plans for a quiet rendezvous over the Holidays in 2008 had been all but solidified, Comet Boethin decided it would rather break up than face an encounter with the Deep Impact space probe. Perhaps it was pent up anger over what Deep Impact had done to Comet Tempel 1, or perhaps (and far more likely) it was the light of Sun or the gravity of her involvement with other planets – whatever the cause, Comet Boethin appears to be no more.

All silliness aside, NASA announced at the end of last week the it’s canceling plans to rendezvous the Deep Impact space probe with Comet Boethin in December of 2008 after the comet went missing.  Although no remnant bodies have been found, it is  assumed Comet Boethin broke up sometime between its 1986 appearance and now.

Before NASA was willing to make the final steering maneuvers necessary to direct Deep Impact to Comet Boethin, they required the mission’s scientists to locate the dormant comet nucleus on its way back into the solar system. This was no small feat! The nucleus was coming in on a trajectory that would line it up with the most star rich regions of the sky. Its precise location wasn’t known because comets’ positions are constantly effected by outgasing and jets of material that act like miniature rockets (thus the need for imaging it before the maneuver). Still, while hard, this task wouldn’t have been impossible if the comet had been there to find. Astronomers used literally every large telescope on the planet (and a few off the planet!) to search for Boethin and it just wasn’t there to be found. According to Karen Meech, an astronomer at the University of Hawaii, they would have found anything down to 0.1 km – 0.2 km in size. It had been believed Comet Boethin was (with the emphasis on was) at least 0.7 km across or larger in 1986.

About this time next year, whatever remains of Boethin should be headed into view and we’ll be able to study just what happened.

And while Boethin heads into the solar system, Deep Impact heads out to a new target: Comet Hartley 2. The comet and space probe will meet in October 2010 (with the closest encounter taking place on 10/11/10). In the interim, the larger of Deep Impacts onboard telescopes will be used to search for transiting extrasolar planets.