In around 10,000 years, the two black holes will combine, causing ripples in the fabric of space-time.
Astronomers have discovered two supermassive black holes that are 99 percent on their way to colliding violently, causing the fabric of space-time to be shattered.
According to a study published Feb. 23 in The Astrophysical Journal Letters, the black holes, which share the moniker PKS 2131-021, are locked in a doomsday dance around 9 billion light-years from Earth. According to NASA, the two objects have been progressively moving near each other for about 100 million years, and now they share a binary orbit.
About 10,000 years from now, the two black holes will merge, sending gravitational waves — ripples in the fabric of space-time originally predicted by Albert Einstein — surging across the universe, the researchers said. Though none of us will witness that epic collision, studying PKS 2131-021 now could reveal new information about how supermassive black holes form and what happens when two of them collide.
Monster's flitters
In this artist's animation, binary black holes whirl around each other. The larger black hole fires a near-light-speed jet of matter into space, which astronomers can detect from Earth.
In this artist's animation, binary black holes whirl around each other. The larger black hole fires a near-light-speed jet of matter into space, which astronomers can detect from Earth. (Photo credit: R. Hurt/Caltech)
Most, if not all, galaxies in the universe include supermassive black holes, which are extraordinarily dark, dense objects hundreds of millions of times more massive than the sun. Astronomers aren't sure how these things come to be so massive, but one theory is when they collide with one other universe's largest black holes result from at least one merger between two smaller black holes, according to NASA. The new study may help to confirm that hypothesis.
PKS 2131-021 is a form of black hole known as a blazar, which is essentially a supermassive black hole directing a jet of supercharged matter right at Earth. That stuff comes from the hot gas rings that form around black holes; when the black hole's enormous gravity pulls that gas in, some of it may escape and be pushed away in a jet of plasma moving at almost the speed of light.
The authors of the new study were observing the brightness of approximately 1,800 blazars distributed throughout the universe when they spotted something unusual: The brightness of blazar PKS 2131-021 changed at regular intervals, so much so that the study authors compared it to the ticking of a clock.
The researchers assumed that the changes were caused by a second black hole pushing on the first as the two objects orbited each other every two years or so, but additional data was needed to see how long this pattern lasted. As a result, the researchers went through 45 years of data from five observatories. The team's expectations for how the binary blazar's brightness should fluctuate over time were confirmed by the extra data.
The two gigantic black holes are huge enough and near enough together that they could generate gravitational waves before colliding, according to the study's authors. PKS 2131-021's future observations will focus on catching those waves in the act.
