An extragalactic outburst whose light hurtled through the inner solar system last fall was 70 times brighter than any other such observed eruption.
An extragalactic outburst whose light hurtled through the inner solar system last fall was 70 times brighter than any other such eruption that scientists have observed, researchers report.
"It is just an absolutely monstrous burst. It is extremely extraordinary; we've never seen anything remotely close to it," Eric Burns, an assistant professor of physics and astronomy at Louisiana State University, said Tuesday during a press conference at the 20th meeting of the American Astronomical Society's High Energy Astrophysics Division in Hawaii.
Astronomers recognize two different classes: short GRBs, which last about two seconds or less, and long ones, which can continue for multiple minutes. The short variety is likely spawned by collisions of superdense stellar corpses known as neutron stars, astronomers say. Most long GRBs, on the other hand, are generated by black holes born as massive stars collapse and die.
The BOAT was a long GRB, so researchers expect a supernova to emerge at its locale, a spot about 1.9 billion light-years from Earth. But they haven't found one yet, despite searching the area with NASA's James Webb Space Telescope and Hubble Space Telescope, along with other instruments. He led an analysis that dug deep into the GRB record, establishing the BOAT's brightness bona fides. And other work showed that this superlative brightness didn't stem from overly powerful jets.
She compared the effect to a garden hose, with the BOAT's jet analogous to the more-intense spray you get by using a constricting nozzle.
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