“After ruling out a range of potential experimental errors, we started to suspect that the interaction between the white dwarf and neutron star was not as simple as had been assumed to date,” concluded Willem van Straten, an astronomer at the Auckland University of Technology, about the detection of Lense-Thirring precession. This relativistic effect first hypothesized a century ago alters the orbit of two compact massive objects in a binary star system. The results of the twenty-year study confirm a prediction of Einstein’s general theory of relativity. When a massive object rotates, general relativity predicts that it pulls the surrounding spacetime around with it, a phenomenon known as frame-dragging.
In the nearby Whirlpool galaxy and its companion galaxy, M51b, two supermassive black holes heat up and devour surrounding material. These two monsters should be the most luminous X-ray sources in sight, but a new study using observations from NASA’s NuSTAR (Nuclear Spectroscopic Telescope Array) mission shows that a much smaller object is competing with the two behemoths.
“We know from theory that black holes and neutron stars form when a star dies, but we’ve never seen them right after they are born. Never!” said Raffaella Margutti, assistant professor of physics and astronomy at Northwestern University about the mysterious bright object that has baffled astronomers dubbed ‘The Cow’. “A ‘lightbulb’ was sitting deep inside the ejecta of the explosion. It would have been hard to see this in a normal stellar explosion. But The Cow had very little ejecta mass, which allowed us to view the central engine’s radiation directly.”