On January 4th 2017, the ground-based twin Laser Interferometer Gravitational-Wave Observatory (LIGO) facilities in Washington and Louisiana detected an event that transpired in our universe over three billion years ago. Yes, you read that right. The LIGO successfully detected the gravitational waves that were caused by the collision of two black holes billions of years before Earth became what it is today.
The event, which is known as GW170104, led to the creation of a single black hole that is estimated to be over forty nine times the mass of our Sun, and marks the third time gravitational waves were picked up by LIGO. Scientists and researchers part of the LIGO Scientific Collaboration (LSC), an international endeavour, published the results of the latest gravitational waves in the Physical Reviews Letter. LSC Spokesperson and Massachusetts Institute of Technology professor David Shoemaker expounded on the team’s findings:
“We have further confirmation of the existence of stellar-mass black holes that are larger than 20 solar masses—these are objects we didn’t know existed before LIGO detected them. It is remarkable that humans can put together a story, and test it, for such strange and extreme events that took place billions of years ago and billions of light-years distant from us.”
First detected by LIGO in 2015, the gravitational waves have helped scientists and researchers determine that at least three black hole mergers have occurred in the past several billion years, and has helped them expand their knowledge on how energy from various events continue to have an effect today. That being said, the attention to detail and fine tuning needed to be able to pick up those effects hasn’t been without toil, as NASA’s Tyson Littenberg explains.
The team of scientists who have worked on LIGO have managed to develop it to the point where it can accurately detect disturbances 10,000 times smaller than an atomic nucleus – which has helped them identify the gravitational waves remnant of long ago collision.
“LIGO could not succeed without the effort and continued support of more than a thousand scientists and engineers from all corners of the globe,” Littenberg said. “Gravitational wave detection is an incredibly challenging endeavor, both scientifically and technologically, and we have only just begun to reap the benefits.”
The LSC, along with NASA and the ESA, are hoping that these latest findings help improve their understanding of space physics as well as the impact of black holes on our universe. Additionally, this research could lead to scientists finally unlocking the mystery as to the creation of black holes as well as their tendency to draw each other closer in order to merge.