June 3, 2013
Astronomers Discover Asteroid Has Much Longer Tail Than Thought
Brett Smith for redOrbit.com - Your Universe Online
Using the new wide-field camera at the WIYN Observatory´s 3.5-meter telescope, astronomers at the facility have discovered that asteroid P/2010 A2's recently-formed tail is much longer than previously believed. The astronomers said the tail is about 620,000 miles long, or about triple the distance from the Earth to the Moon.
The scientists were able to see the complete tail using the new One Degree Imager (ODI) -- a wide-field camera at the WIYN telescope on Kitt Peak in Arizona.
"Previous images of A2 clearly indicated the tail extended beyond those relatively small fields of view: we wanted to use the superb image quality over a wide field that ODI offers to see just how much,” said Jayadev Rajagopal, WIYN scientist at the National Optical Astronomy Observatory (NOAO). “But I don't think we were quite expecting to see a tail that extends out to and beyond even the ODI field!"
Owned and operated by the WIYN consortium, which includes the University of Wisconsin (WISC), Indiana University, Yale University, and NOAO, the ODI camera is able to capture a region of the sky about the size of a full moon. However, a planned upgrade will increase the size of the field four-fold, according to a statement from the consortium.
Asteroids typically don´t have tails, but imaging advances have allowed for the discovery of a small class of orbiting space rocks that do eject dust. Asteroid P/2010 A2 was initially spotted by the Lincoln Near-Earth Asteroid Research (LINEAR) telescope and follow-up Hubble images showed it to have a highly unusual X-shape with a tail, suggesting to astronomers that the asteroid was disrupted recently, possibly by a collision or internal disruption. A2 orbits within the hot, inner regions of the asteroid belt unlike similar objects.
The disruption of asteroid A2 happened about three-and-a-half years ago and has resulted in centimeter-sized particles being spread out in a tube-like tail, the astronomers said in a statement. Because the earth inhabits the same orbital plane as this debris, we are only able to observe a thin line or tail-like structure.
In time, the tail particles will most likely form a “meteor stream” that surrounds the sun. Meteor streams are observed from Earth as "shooting stars" when our planet passes through the field of orbiting particles. Debris from A2 will contribute to the dust cloud, called zodiacal dust, currently spread across our Solar System. WIYN scientists said they expect ODI images to help identify the role of asteroids in keeping this cloud replenished.
The public-private partnership of the WIYN Consortium was the first of its kind and has been in operation for almost two decades. The telescope at its Arizona facility incorporates many technological breakthroughs, such as a modern dome and actively controlled mirror.
According to a statement on their official website, the consortium is currently seeking new partners to join its ranks in an effort to secure the future operations of the WIYN 3.5-m telescope for the near future. However, the organization is also interested in securing potential partners for a new consortium that would operate both the WIYN and Mayall 4-m telescope as a two-telescope system on Kitt Peak.