Scientists searching for astronomical objects in the early universe, not long after the Big Bang, have made a record-breaking, two-for-one discovery.
Using ground-based telescopes, a team of astronomers have discovered the most distant supermassive black hole ever found.
The black hole has a mass 800 million times greater than our sun, which earns it the “supermassive” classification reserved for giants like this.
Astronomers can’t see the black hole, but they know it’s there because they can see something else: A flood of light around the black hole that can outshine an entire galaxy.
This is called a quasar, and this particular quasar is the most distant one ever observed.
The light from the quasar took more than 13 billion years to reach Earth, showing us a picture of itself as it was when the universe was just 5 percent of its current age.
Back then, the universe was “just” 690 million years old. The hot soup of particles that burst into existence during the Big Bang was cooling rapidly and expanding outward.
The first stars were starting to turn on, and the first galaxies beginning to swirl into shape.
Quasars from this time are incredibly faint compared to the nearest quasars, the light from some of which takes just 600 million light years to reach the Earth.
Black holes, mysterious as they are, are among the most recognizable astronomical phenomena in popular science.
They’re pretty straightforward: Black holes are spots in space where the tug of gravity is so strong that not even light can escape.
They gobble up gas and dust and anything that comes near, growing and growing in size. A supermassive black hole sits in the center of virtually all large galaxies, including the Milky Way.
Astronomers can infer their existence by watching fast-moving stars hurtle around a seemingly empty, dark region.
Quasars, meanwhile, are a little trickier to understand, and you’d be forgiven for thinking they sound like something out of Star Trek.
A quasar is, to put it simply, the product of a binge-eating black hole. A black hole consumes nearby gas and dust inside a galaxy with intense speed, and the violent feast generates a swirling disk of material around it as it feeds.
The disk heats up to extreme temperatures on the order of 100,000 degrees Kelvin and glows brightly. The resulting light show is what we call a quasar, and what a light show it is.
The more material a black hole consumes, the bigger it becomes. Eventually, the black hole drains the surrounding area of material and has nothing to eat.
The luminous disk around it shrinks and fades, and the quasar is extinguished.
In this way, quasars—and the black holes that power them—are like volcanoes, erupting under one set of conditions and settling into dormancy under another.
Quasars were first detected in 1963 by the Dutch astronomer Maarten Schmidt with California’s Palomar Observatory.
Astronomers thought these newly discovered points of light were stars because of their extreme brightness.
But when they studied the spectrum of their light, they were stunned to find the “stars” were more than a billion light-years away.
When light travels through space, it gets stretched thanks to the constant expansion of the universe. As it moves, it shifts toward redder, longer wavelengths.
Astronomers can measure this “redshift” to figure out how long the light took to reach Earth, which indicates how far a certain object is.
Schmidt and his fellow astronomers knew that for stars to appear so luminous to Earth from such great distances was impossible. They were dealing with completely new phenomena.
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