The wobbling orbit of a pulsar proves Einstein right, yet again
Chalk up yet another win for Einstein. A twist in the fabric of spacetime — predicted by the physicist’s theory of general relativity (SN: 10/7/15) — is causing the orbit of one stellar corpse to teeter around another stellar corpse, researchers report. And the relativistic corkscrew is helping astronomers reconstruct the final days of these two long-dead stars. According to general relativity, any spinning mass drags spacetime around with it, like a hand mixer in molasses. One way to see this “frame dragging” is to keep a careful eye on anything circling the spinning object on a tilted orbit — the spacetime maelstrom will make the orbit wobble, or precess. For the last 20 years, researchers have been using radio telescopes to track the motion of a pulsar, the dense remains of a massive star that went supernova, as it orbits a spinning white dwarf, the core of a lighter star that died less violently. The pulsar, dubbed PSR J1141–6545, emits a steady...