Dead Star Set to Escape the Milky Way
slackah wrote to mention a NewScientist.com article discussing a fast-moving stellar corpse on its way out of our galaxy. From the article: "The object, called B1508+55, is a rotating neutron star, or pulsar. It is the superdense core of a massive star that exploded as a supernova about 2.5 million years ago. The explosion seems to have ejected the pulsar with such force that it will eventually escape the Milky Way entirely, says team member Shami Chatterjee, an astronomer with NRAO and CfA."
Ok, the article didn't say anything about when it will leave the milky way. It just said that B1508+55 was going to leave the milky way, and that it had been traveling for 2.5million years from its point of origin in Cygnus. That translates to a velocity of 1100km/s or being able to cross 1/3 of the night sky from the time of birth to the present.
There are two things that excite me about this. 1) B1508+55 is a massive radio emitting object which is boldly going into the intergalactic space where all that putative dark matter is supposed to be. If its path bends we might end up discovering a "dark galaxy". Of course someone with access to human astronomy records must be around to observe this when it happens.
2) Cygnus spits out a lot of these objects. Maybe if we get a very much faster one, we can have a more convenient probe.