Using Chandra X-ray Observatory by NASA and the XMM-Newton by ESA, a mysterious x-ray signal has been observed in a study of galaxy clusters. One exciting possibility may be that these X-rays might be the result of the decay of sterile neutrinos – a particle that is a very good candidate for dark matter, but it doesn’t certainly imply that all dark matter is composed of these particles.Although this is a thrilling finding, it still has to be determined if it is plausible that dark matter has been observed, so the results must be confirmed with additional data. Dark matter being an explanation for the X-ray’s is very unlikely, but it is still a very exciting possibility. XMM-Newton and Chandra discovered a strange X-ray emitted in a line, which is a point of force from a particular X-ray light wavelength. Astronomers have found this emission line with dozens of other galaxy clusters, including the Perseus galaxy cluster, by using the Chandra and XMM-Newton information.
Other explanations, if the X-ray emission line is indeed real, include normal matter in the cluster that could’ve produced the line, and that would result in unlikely changes to our understanding of physical condition in the galaxy cluster or the details of the atomic physics of extremely hot gases. The information provided by JAXA and Chandra’s Suzaku mission on the huge number of the galaxy clusters has to be used to confirm about the unknown-ray signal. Astronomers may not be able to know for certain though, until Astro-H launches a new type of X-ray detector that can measure the line with more precision.