The giant twin facilities of the Laser Interferometer Gravitational Wave Observatory (LIGO) in Louisiana and Washington and the Italy-based Virgo Interferometer.
Now they can work again.
The systems can detect gravitational waves due to a series of high power lasers and mirrors. Each device is arranged in an "L" shape with vertical arms that extend for miles. At the corner of the L, a laser fires down both arms and bounces off the mirrors before being sent back to recombine.
Gravitational waves emit very, very very very very weak signals This can disrupt the laser's path and allow scientists to recognize these universe-teetering events.
Now that LIGO has upgraded the performance of its lasers and replaced the mirrors, LIGO now has a 40 percent increase in sensitivity in its last run. In this way, the two institutions can explore even more space in the search for the waves. Similarly, Virgo has approximately doubled its own sensitivity.
With all three machines running better than ever before, the detection and localization of "extreme cosmic events" that cause gravitational waves to collapse like black holes or collapse neutron stars should become even more uniform – it's much easier to get the exact position to determine the waves in space.
"As our three detectors now operate with significantly improved sensitivity, the global LIGO-Virgo detector network allows for more accurate triangulation of the gravitational-source waves," said Jo van den Brand, a spokesman for the collaboration, in a press release.
In earlier detection runs, LIGO inspected the universe at a distance of up to 360 million light-years away. Since 2015, the facilities have detected eleven extreme cosmic events, including ten black hole mergers and a neutron star collision. With the upgrade, the plants will be able to throw another 190 million light-years into the universe.
"If LIGO and Virgo observe together for the next year, we will certainly see many more gravitational waves from the sources. We have seen so far," said Peter Fritschel, chief detector at LIGO.
"We are also looking forward to new events, such as the merging of a black hole and a neutron star."