A massive burst of energy exploded from a far-off neutron star last December, the brightest flash of light ever detected from beyond the solar system, scientists said.
The Dec 27 flare was by far the largest of three such giant outbursts of gamma rays detected in the last 35 years from neutron stars, the densely packed and supercharged remnants of a collapsed star. “This is a once-in-a-lifetime event,” David Palmer, a scientist at the Los Alamos National Laboratory in New Mexico and lead author of a paper on the flare.
The energy burst, packing more energy than the sun emits every 150,000 years, was not visible to humans, and the gamma rays were blocked by the Earth’s atmosphere as they rushed by. Scientists said some operators of low-frequency transmitters were able to detect it.
NASA’s new observatory named Swift for its speedy pivoting and pointing is among the instruments that detected the flare. Swift was launched last November to probe the workings of black holes. The satellite, controlled by scientists at the Goddard Space Flight Center in Greenbelt, is designed to detect gamma ray outbursts and pivot to record them. It also recorded the afterglow of the blast.
The December burst lasted a tenth of second and came from a neutron star 50,000 light years away from Earth in the constellation Sagittarius. Called SGR 1806-20, it is one of only about 12 known magnetars, a neutron star with a magnetic field that is trillions of times stronger than that of Earth. Scientists believe the magnetic field of the magnetars can shift like an earthquake, causing it to eject a huge burst of energy.