APOD 3.3

http://apod.nasa.gov/apod/ap110204.html

 

Zeta Oph: Runaway Star  (4 Feb. 2011)

                    What to me looks like a wave crashing through the cosmos is in actuality the arcing interstellar bow wave or bow shock of the runaway star, Zeta Oph. This portrait comes from the WISE Spacecraft and was taken by infrared imaging. In this false-color view the bluish Zeta Oph is about twenty times more massive than the Sun and lying near the center of the frame, it is moving toward the top at twenty-four kilometers per second. It has strong stellar wind which precedes it, compressing and heating the dusty interstellar material and shaping the wave-like shock front. Around it are clouds of material that appears to be still or relatively calm compared to the bow wave. The reason why Zeta Oph is moving is because it was likely once a member of a binary star system but its companion star was larger and thus had a shorter lifespan. When the companion exploded as a supernova losing enormous amounts of mass, Zeta Oph was flung out of the binary system. At about 460 light-years away, Zeta Oph is 65,000 times more luminous than the Sun and would be one of the brightest stars if it weren't surrounded by so much dust. It's estimated distance is about twelve light years.