Log in

View Full Version here: : Colossal tail trails Mira


glenc
16-08-2007, 05:23 AM
A distant star that hurtles through space at extraordinary speeds has a huge, comet-like tail trailing in its wake, astronomers say.
The appendage, which measures a colossal 13 light years in length, was spotted by Nasa's Galaxy Evolution Explorer (Galex) space telescope.
The researchers said that nothing like it had ever been spotted around a star.
They believe the star, known as Mira, will help them to study what happens as stars meet their demise.
Mark Seibert, a co-author of the paper, which was published in the journal Nature, and a scientist at the Carnegie Observatories in Pasadena, said: "This is an utterly new phenomenon to us, and we are still in the process of understanding the physics involved."
Racing through space
Mira (also called Mira A) has captivated astronomers for more than 400 years.
It sits about 350 light-years from Earth in a constellation known as Cetus, and is accompanied in orbit by a smaller secondary star, called Mira B, forming a binary system.
Billions of years ago, Mira would have been much like our Sun, but as it now enters its death-throes it has swollen into a type of star known as a red giant.
As it races through space at 130km/s (80 miles per second) it sheds vast amounts of material.

More at: http://news.bbc.co.uk/2/hi/science/nature/6947607.stm
Image shows the tail 13 light years in length

sheeny
16-08-2007, 07:51 AM
Cool! Thanks Glen!

Al.

Ric
16-08-2007, 11:29 AM
Great stuff Glen, a very amazing and interesting article.

Cheers

Bobj
16-08-2007, 06:51 PM
Have a listen:
http://science.nasa.gov/headlines/y2007/images/mira/audio/story.m3u

CoombellKid
16-08-2007, 07:06 PM
13 lightyears now that's a tail!!!!

Great article too!

regards,CS

h0ughy
16-08-2007, 10:09 PM
OK so who has imaged this,LOL

glenc
17-08-2007, 05:41 PM
Explanation: To seventeenth century (http://www.seds.org/%7Espider/spider/Vars/Add/var-dis.html) astronomers, Omicron Ceti or Mira was known (http://www.aavso.org/vstar/vsots/mirahistory.shtml) as a wonderful star, a star whose brightness could change dramatically in the course of about 11 months. Mira is (http://www.seds.org/%7Espider/spider/Vars/mira.html) now seen as the archetype of an entire class of long-period variable stars. Surprisingly, modern astronomers have only recently discovered another striking characteristic of Mira -- an enormous comet-like tail nearly 13 light-years long. The discovery (http://www.galex.caltech.edu/MEDIA/2007-04/) was made using ultraviolet image data from the Galaxy Evolution Explorer (GALEX (http://www.galex.caltech.edu/)) satellite. Billions of years ago Mira was likely similar to our Sun, but has now become a swollen (http://antwrp.gsfc.nasa.gov/apod/ap060722.html) red giant star, its outer layers of material blowing off into interstellar space. Fluorescing in ultraviolet light, the cast off material trails behind the giant star as it (http://www.galex.caltech.edu/MEDIA/2007-04/images.html#fig5) plows through the surrounding interstellar medium at 130 kilometers per second. The amount of material in Mira's tail is estimated to be equivalent to 3,000 times the mass of planet Earth. About 400 light-years away toward the constellation Cetus, Mira is presently too faint to be seen by the unaided eye, but will become visible again (http://antwrp.gsfc.nasa.gov/apod/ap070221.html) in mid-November.
http://antwrp.gsfc.nasa.gov/apod/

Doug
17-08-2007, 06:18 PM
There seems to be no reason offered why the tail is curved as though Mira is in a curved trajectory around some relatively close CofG.