A star mounted in ice Astronomers have spotted a disk of dust and ice ringing a young sun like star 165 many years away.The icy signature of the disk and the collisions between bodies inferred to be taking place there suggest it is like the sun's kuiper belt, a disk of small icy bodies that offers beyond neptune. "Right here is first time there's evidence for water ice around a main sequence star, the work has been accepted for bible in the astrophysical journal, and a preprint was posted last week to the net server arxiv1. Previous few, hundreds of debris disks http://www.ed5.co.uk/accessories.html have been located around young stars.The infrared radiation the disks emit can often tell their temperature, and this has shown that a lot of are cold;But to tell apart definitively cold dust from cold ice has proved tough. "This is a really difficult observation to do, reports chen. Due to their study of hd 181327, throughout constellation of pictor, chen and her colleagues used several assets, since hubble space telescope and the gemini south telescope, an 8 metre ground based telescope in chile that is essential in the near infrared.But the key findings were from the spitzer space telescope, which has cryogenically cooled cameras that can see emitted infrared radiation hidden from earthbound telescopes by the air.Employing spitzer, chen and her colleagues could actually make out a tiny dip in the infrared spectrum emitted by the debris disk.The dip was at a wavelength that might be preferentially absorbed by particles of ice. Brief grains"It's a great advancement in making an observation with this new capability, says jordan meyer, an astronomer at steward observatory at www.ed5.co.uk the university or of arizona in tucson.Stated meyer, who was not connected with the study, notes that the key observation scaled like just a few data points, an design that could be considered"Dicey,"It's a really tantalizing piece of evidence but not yet the final word, he states.For it to produce up the way it does, the groups in the belt must be colliding, chen tells me.The sort of ice grains that these findings pick up would last only a bit more than a thousand years in the harsh light of their star, and so there ought to be a constant source of replenishment such as collisions between larger bodies. One side of the belt is brighter than one more, both in the way it reflects light and in what way it emits in the infrared, which might mean there are many more icy grains in that part of the belt.Chen says this shows that bigger bodies in the belt collided ed5 recently, creating debris that has not yet had time to even itself out concerning the belt. In house to the icy belt, the astronomers find an serious lack of debris.The bodies in the sun's kuiper belt are usually remnants of the disk from which the planets proper formed. The scope for following up this work by finding ice in other kuiper belts, even so, is fixed.Spitzer's Cheap Paul Smith UK cryogenic cooling will fail when it has no liquid helium in early 2009;When the telescope warms up such type of observation will become impossible. "The goal is to waste as couple of seconds on this telescope as possible, says kennedy.
