Gravitational waves, theorized by Albert Einstein in 1916, were first detected in 2015. Now could they be heard?
Scientists working with the North American Nanohertz Observatory for Gravitational Waves, also known as NANOGrav, managed to “hear” the sound of gravitational waves, which is produced by the collision of supermassive black holes.
Gravitational waves, theorized by Albert Einstein more than 100 years ago, represent a milestone in the science and exploration of the universe. Detecting them completely changes the way we understand our existence.
A gravitational wave had been recorded in 2015, by the LIGO experiment (Gravitational Wave Laser Interferometry Observatory). At that time, the wave was recorded in instruments placed on the earth’s surface.
The latest in this universal phenomenon is that scientists found gravitational waves in data from 15 years of viewing more than 60 pulsars collected by the Arecibo Observatory in Puerto Rico, the Green Bank Telescope in West Virginia, and the Very Large Telescope. Array in New Mexico, CNN highlighted.
“When gravitational waves pass between the Earth and a pulsar, the synchronization of the pulsar’s radio waves is interrupted,” explain the experts who “heard” the gravitational waves.
Experts say that these gravitational waves are the most powerful ever detected. This element makes them think that they occurred as a result of the collision of supermassive black holes, which exceed the energy of the “regular” ones by a million.
“It’s like a chorus, with all these pairs of supermassive black holes resonating at different frequencies. This is the first evidence of the gravitational wave background. We have opened a new window of observation of the universe”, explains Chiara Mingarelli, co-author of the study and NANOGrav scientist.
The gravitational wave background is something like cosmic noise. It is made up of ultra-low frequency gravitational waves and as black holes collide in the universe, these waves hum and resonate together in the background.
Gravitational waves travel at the speed of light, but astronomers realized that a single rise and fall of one of the waves could take years or decades to pass due to the domino effect of space-time.
“At one time, scientists were concerned that supermassive black holes in binaries would orbit each other forever, never getting close enough to generate a signal like this,” said Dr. Luke Kelley, president of the NANOGrav astrophysics group.
“But now we finally have strong evidence that many of these extremely massive and close binaries exist. Once the two black holes get close enough to be seen by the pulsar synchronization arrays, nothing can stop them from merging in a few million years,” Kelly said.