Tuesday, January 25, 2011

Zeta Ophiuchi With A Bullet

Zeta Ophiuchi is a blue supergiant star 20 times the mass of our sun...

Image credit: NASA/JPL-Caltech/UCLA

It's located in the constellation Ophiuchus (yeah, the "new" 13th sign of the zodiac...Peh!) but an explosive supernova of its former companion star sent it zipping through the galaxy at 24 kilometers per second.  On Earth a pretty snappy rifle bullet travels a little over one kilometer per second, and only for a couple seconds.  As Zeta Ophiuchi plows through the interstellar medium its solar wind compresses gas and dust into a bow shock.  Other than the blue-white light from "Zeta Oph" none of this adventure can be seen as light to the human eye.  But NASA's Wide-field Infrared Survey Explorer (WISE) examines the cosmos in the infrared so the shock wave can now be seen plain as day.  The linked articles describe all the science better than I can ever hope to but this stuff is great fun to ponder.