After 26 years of slumber, a black hole woke up and unleashed a giant blast of plasma into space at nearly the speed of light.
Such events are very rare, but astronomers managed to record incredible footage of the aftermath this summer.
The black hole is part of star system called V404 Cygni. The black hole is about 12 times more massive than the sun and is nearly 46 quadrillion miles away from Earth. Over at least the last few years, it has quietly feasted on a neighboring star, sucking in more and more of its plasma.
All of that hot gas spiraled into a disc around the black hole, but eventually no more could fit — triggering a blinding eruption or "black hole jet." The jet shot out hot plasma, radio waves, X-ray light, and visible light.
This particular jet was so bright astronomers could spot it from Earth by peering into a small 14-inch telescope, according to the University of Oxford's science blog.
NASA put together this animation of what the explosion might have looked like around the black hole (similar to how NASA depicts an "X-ray nova"). You can see it sucking in matter from its nearby star, then bursting:
Astronomers missed the beginning moments of the eruption. However, an orbiting satellite picked up an X-ray burst from the explosion as it happened and sent out an alert.
Several astronomers immediately pointed telescopes at the black hole, since catching a jet in action is a once-in-a-career kind of opportunity, according to Oxford's science blog.
The Arcminute Microkelvin Imager Large-Array (AMI-LA) telescope caught the blast about two hours after it started. AMI-LA eventually returned this incredible, pulsating recording of the aftermath, as seen in radio waves:
The eruption happened about 7,800 years ago but — thanks to the limited speed of light — light from the event only reached Earth on June 15, 2015. The black hole continued shooting out energy and blobs of plasma for about 30 days after the initial jet, and it has since returned to slumber.
V404 Cygni produced similar outbursts in 1989, 1956, and 1938. This suggests that all that star gas that builds up around the black hole reaches a tipping point every two or three decades — when the gas disc collapses, triggers a violent outburst, and blasts all kinds of energy across the electromagnetic spectrum into space.
Researchers now want to compare this black hole jet to those emanating from supermassive black holes that sit at the center of galaxies, including our own Milky Way galaxy. They hope the comparison will help us understand more about how our home galaxy evolved, and what may happen to it in the future.
