The puzzle at the core of the unexplained, bright gamma-ray light point in the sky has been solved: a dangerous spider star is flaking a second, wimpier star in pieces, sending gamma-radiation rapid-fire bursts in the process.
As previously mentioned by Live Science, "Black widows" and "redbacks" in astronomy are species of neutron stars, the ultradense remnant cores of giant stars that exploded. At daily intervals, certain neutron stars, or pulsars, spin, blinking like lighthouses. Millisecond pulsars are the quickest-spinning of them. When a millisecond pulsar is locked with a lightweight star in an unusual, close orbit, it steadily shreds the companion with each rotation to pieces.
Researchers have speculated that PSR J2039–5617 contained a millisecond pulsar and a second star after its observation in 2014. The bright source of X-rays, gamma rays, and visible light closely mirrored such a system's predicted characteristics. But it took telescope data scans and more number-crunching to show it than a modern laptop machine might achieve in a century.
The researchers relied on the computational resources of Einstein@Home, a project of the LIGO Science Collaboration and the Max Planck Institute of Germany, to prove that the star system was actually a redback, where more than 500,000 volunteers let their idle machines operate together on complicated astronomy problems.
The researchers announced in two months that a lethal redback is housed in PSR J2039-5617, heating up one side of its companion star so that the side looks brighter and bluer. "The massive gravity of the redback also distorts the shape of its companion, causing "the apparent size of the star to differ over the orbit," lead author Colin Clark, an astronomer from the University of Manchester, said in a statement, "The star's apparent size differs over the orbit.