A pair of merging black holes show extreme signs of gravity-induced orbital precession, or wobbling, as predicted by Albert Einstein's theory of general relativity.
This swaying, called Precession, happens when an object's orbit or rotation gradually alters over time; a popular illustration is how a spinning top starts to spin at a different angle as it slows down.
The geometry of such an object's orbit changes with time due to gravity-induced orbital precession, which is a result of general relativity's prediction that massive objects bend space-time.
The orbits of two neutron stars orbiting each other have been subject to this effect, but it had only been seen extremely faintly and very occasionally.
Some of the most extreme occurrences in the universe are black hole collisions. The two enormous, invisible masses swirl toward one another, disrupting spacetime and causing reverberations throughout the cosmos.
Gravitational waves are those ripples that eventually wash across the Earth and can be "heard" by some extremely sensitive detectors in the US, Italy, and Japan.
“It’s 10 billion times faster than what was found in earlier measurements, so it really is the most extreme regime of Einstein’s theory where space and time are warped and distorted in completely crazy ways,” says Hannam.
On-graph Visualization of Binary Black Hole Merger
On January 29, 2020, one such ripple swept over our planet. The Laser Interferometer Gravitational-Wave Observatory (LIGO) in the United States and Virgo, a third detector, both detected it.
The distinctive chirp from the detectors showed that two black holes, one about 40 times the mass of the sun and the other around 22 times, had collided.
The team used data that was originally gathered in 2020 by three gravitational wave detectors located in the US, Italy, and Japan.
A prior investigation indicated no precession, but Hannam and his team discovered that the signal was best explained by one of the black holes, spinning at virtually the maximum rate permitted by general relativity and causing the system's orbit to precess.