US scientists map star’s death by black hole

SAN FRANCISCO

NASA scientists announced Monday that for the first time they have been able to map a star’s path to destruction within a black hole.

A star similar to the sun wandered too close to the huge black hole at the center of its galaxy. It circled around the black hole that was roughly 13 times the size of the sun, in what researchers called a “death spiral” until it was finally ripped apart by the extreme gravitational force of the black hole.

In an event known as ASASSN-14li, the majority of the star was swallowed up by the celestial beast, while the star’s shattered debris circled the black hole in a rapidly spinning disk.

The star’s violent death happened 290 million years ago, but light from ASASSN-14li did not reach telescopes until recently.

In 2014, NASA’s Swift satellite telescope detected radiation waves from the event. Using those observations, researchers from NASA and the Massachusetts Institute of Technology were able to map the star’s death in detail.

In a paper published in The Astrophysical Journal Letters, astronomers discussed how the discovery reveals new data about how black holes swallow stars. Instead of completely sucking in entire stars, particles from the disintegrated star smash into each other as they orbit around the black hole.

"We discovered brightness changes in X-rays that occurred about a month after similar changes were observed in visible and UV light," lead researcher Dheeraj Pasham said in a statement. "We think this means the optical and UV emission arose far from the black hole, where elliptical streams of orbiting matter crashed into each other."

Black holes are one of the most fearsome objects in space but are poorly understood by scientists. Previous observations of black holes destroying stars have puzzled scientists because it was not clear where stars were located when they were destroyed.