Weekend Image: Gigantic Loop of Black Holes and Neutron Stars
Arp 147 contains the remnant of a spiral galaxy (right) that collided with the elliptical galaxy on the left. This collision has produced an expanding wave of star formation that shows up as a blue ring containing in abundance of massive young stars. These stars race through their evolution in a few million years or less and explode as supernovas, leaving behind neutron stars and black holes.
An X-ray source is also detected in the nucleus of the red galaxy on the left and may be powered by a poorly-fed supermassive black hole. This source is not obvious in the composite image but can easily be seen in the X-ray image. Other objects unrelated to Arp 147 are also visible: a foreground star in the lower left of the image and a background quasar as the pink source above and to the left of the red galaxy.
Infrared observations with NASA's Spitzer Space Telescope and ultraviolet observations with NASA's Galaxy Evolution Explorer (GALEX) have allowed estimates of the rate of star formation in the ring. These estimates, combined with the use of models for the evolution of binary stars have allowed the authors to conclude that the most intense star formation may have ended some 15 million years ago, in Earth's time frame.
These results were published in the October 1st, 2010 issue of The Astrophysical Journal. The authors were Saul Rappaport and Alan Levine from the Massachusetts Institute of Technology, David Pooley from Eureka Scientific and Benjamin Steinhorn, also from MIT.
The Daily Galaxy via nasa.gov
Comments
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I was wondering why their magnetic fields don't repel?
Posted by: katesisco | November 18, 2012 at 05:58 AM
The magnetic fields of The two galaxies? The galaxies are pretty much heading away from each other now. Even before the galactic collision, there would not have been a large enough coherent magnetic field around an entire galaxy to prevent a collision. I can't even really guarantee you that there is such a thing as a galactic magnetic field. That kind of vector math is way above my pay grade! :-)
Posted by: Kbryant | November 18, 2012 at 07:46 PM
That image is fascinating!
Posted by: Xantos | December 27, 2012 at 09:13 AM