Thanks to the X-Ray Imaging and Spectroscopy Mission, or XRISM, University of Michigan researchers are helping chip away at one of astronomy’s cosmic mysteries: The universe’s most massive galaxies appear to be missing stars.
Compared with theoretical expectations, these galaxies contain less stellar mass than anticipated, suggesting something has suppressed star formation. Working with data collected by the XRISM spacecraft, U-M doctoral student Xin “Cindy” Xiang has found evidence that backs one explanation for this discrepancy. Namely, black holes are at the core of it.
Black holes are famous for trapping anything, including massless particles of light, that gets too close. But beyond that threshold, a black hole’s immense gravity can also create what’s known as an accretion disk, which emits oodles of light, including X-rays.
The disk is an incredibly energetic environment where the black hole collects and stirs infalling gas and dust. Friction and gravity atomize the material and can even peel electrons off of those atoms, creating a very hot, very bright plasma. Like a bubbling cauldron, this disk can also fling out material, creating winds so powerful they could blow away the gas that galaxies need to form new stars.
Read more about it in detail on Michigan News.
