A mysterious X-ray signal has been found in a detailed study of galaxy clusters using NASA’s Chandra X-ray Observatory and ESA’s XMM-Newton. One intriguing possibility is that the X-rays are produced by the decay of sterile neutrinos, a type of particle that has been proposed as a candidate for dark matter.
“We know that the dark matter explanation is a long shot, but the pay-off would be huge if we're right,” said Esra Bulbul of the Harvard-Smithsonian Center for Astrophysics (CfA) in Cambridge, Mass. who led the study. “So we're going to keep testing this interpretation and see where it takes us.”
There are ways that normal matter in the cluster could have produced the line, although the team’s analysis suggested that all of these would involve unlikely changes to our understanding of physical conditions in the galaxy cluster or the details of the atomic physics of extremely hot gases.
originally posted by: pheonix358
Once we discover how they overlay the signal on the X-ray band we will no doubt be listening to Alien Rock and Roll.
Yes it seems like every time we answer a question we find another puzzle, but I think we've made some progress in cosmology. The dark mater explanation may be a long shot as they suggest but whatever the cause, it could take decades to figure out.
originally posted by: soulshn
Never ceases to amaze me that as we learn more about the universe we also learn more about how little we know. I've always contended that the universe is a place far too complex for us to grasp in this plane of existence.