LIGO detects its second neutron star collision, but gains few clues
HONOLULU — For the second time, a collision between two neutron stars in another galaxy has rattled a gravitational-wave detector on Earth. But this duo is being much more coy than the first. In 2017, astronomers announced with much fanfare that they had detected ripples in spacetime, from the merging of two neutron stars, the ultradense remains of massive stars (SN: 10/16/17). Observatories around the world and in space witnessed a simultaneous flash of radiant energy, light from all across the electromagnetic spectrum. Now, gravitational waves from a second neutron star smashup have been detected. But unlike the first detection, researchers were not able to pinpoint the collision’s location on the sky and did not see an accompanying burst of light. Katerina Chatziioannou, an astrophysicist at the Flatiron Institute in New York City, presented the results January 5 at meeting of the American Astronomical Society. The event was picked up on April 25, 2019, during the third observing run of the LIGO and Virgo gravitational-wave observatories. However, only...