XMM-Newton spacecraft tagged posts

Credit: Harvard-Smithsonian Center for Astrophysics

The center of the Milky Way galaxy is currently a quiet place where a supermassive black hole slumbers, only occasionally slurping small sips of hydrogen gas. But it wasn’t always this way. A new study shows that 6 million years ago, when the first human ancestors known as hominins walked the Earth, our galaxy’s core blazed forth furiously. The evidence for this active phase came from a search for the galaxy’s missing mass.

Measurements show that the Milky Way galaxy weighs about 1-2 trillion times as much as our Sun. About 5/6 of that is in the form of dark matter. The remaining 1/6 of our galaxy’s heft, or 150-300 billion solar masses, is normal matter...

Far-IR Planck 857 GHz (left panel), mid-IR WISE 12µm (central panel, image from Meisner & Finkbeiner 2014) and velocity integrated CO image (right panel, from CfA CO survey of Dame et al. 2001) around Kappa Ori. Green symbols mark the positions of WISE objects with IR excess. Contours are the footprints of XMM-Newton observations. The dust ring is visible at far-IR and millimeter wavelengths while it appears like a bubble of diffuse emission in mid IR. Credit: Pillitteri et al., 2016.

Astronomers have spotted a star-forming ring around a distant star Kappa Ori at the south-eastern corner of the constellation of Orion. The star, also known as Saiph, is a supergiant with a mass of approximately 15 solar masses ~650 light years from Earth...