Posted on by Evan Gough

Hubble Has Looked at the 2017 Kilonova Explosion Almost a Dozen Times, Watching it Slowly Fade Away

An artistic rendering of two neutron stars merging. Credit: NSF/LIGO/Sonoma State/A. Simonnet

In 2017, LIGO (Laser-Interferometer Gravitational Wave Observatory) and Virgo detected gravitational waves coming from the merger of two neutron stars. They named that signal GW170817. Two seconds after detecting it, NASA’s Fermi satellite detected a gamma ray burst (GRB) that was named GRB170817A. Within minutes, telescopes and observatories around the world honed in on the event.

The Hubble Space Telescope played a role in this historic detection of two neutron stars merging. Starting in December 2017, Hubble detected the visible light from this merger, and in the next year and a half it turned its powerful mirror on the same location over 10 times. The result?

The deepest image of the afterglow of this event, and one chock-full of scientific detail.

Continue reading “Hubble Has Looked at the 2017 Kilonova Explosion Almost a Dozen Times, Watching it Slowly Fade Away”
Posted on by Evan Gough

It Looks Like LIGO/Virgo Have Detected a Black Hole Eating a Neutron Star. For the First Time Ever

A new signal detected by LIGO/Virgo may be the so-called ‘holy grail’ of astrophysics: the merger of a neutron star and a black hole. They’ve discovered pairs of black holes merging, and pairs of neutron stars merging, but until now, not a neutron star-black hole pair.

Continue reading “It Looks Like LIGO/Virgo Have Detected a Black Hole Eating a Neutron Star. For the First Time Ever”
Posted on by Matt Williams

New Gravitational Waves Detected From Four More Black Hole Mergers. Total Detections up to 11 Now

Graphic showing the masses for black holes detected through electromagnetic observations (purple); the black holes measured by gravitational-wave observations from LIGO and Virgo (blue); neutron stars measured with electromagnetic observations (yellow); and the masses of the neutron stars that merged in an event called GW170817, which were detected in gravitational waves (orange). Credit and ©: LIGO-Virgo/Frank Elavsky/Northwestern

On February 11th, 2016, scientists at the Laser Interferometer Gravitational-wave Observatory (LIGO) made history when they announced the first-ever detection of gravitational waves (GWs). Since that time, multiple detections have taken place and scientific collaborations between observatories  – like Advanced LIGO and Advanced Virgo – are allowing for unprecedented levels of sensitivity and data sharing.

Previously, seven such events had been confirmed, six of which were caused by the mergers of binary black holes (BBH) and one by the merger of a binary neutron star. But on Saturday, Dec. 1st, a team of scientists the LIGO Scientific Collaboration (LSC) and Virgo Collaboration presented new results that indicated the discovery of four more gravitational wave events. This brings the total number of GW events detected in the last three years to eleven.

Continue reading “New Gravitational Waves Detected From Four More Black Hole Mergers. Total Detections up to 11 Now”