NASA's orbiting telescope NuSTAR has found five supermassive black holes that were previously hidden behind clouds of gas and dust.
Looking deep into the night sky, it's hard to imagine that among those twinkling lights there are millions of invisible stars feasting on cosmic matter.
Those invisible spheres are known as black holes, and NASA's NuSTAR mission discovered five more of them earlier this week.
Their discovery could open the door to finding millions more black holes. Here are five ways they will help us learn more about the universe:
Black holes are a big deal
Black holes mainly occur after a supernova star – about 10 times larger than our sun – explodes and sends its matter shooting into the universe.
That matter condenses into a black sphere about the size of New York City. Yet despite its size, the weight of that small sphere has a gravitational force so strong not even light can escape its pull, NASA says.
An artist's concept of a hidden black hole (NASA / ESA)
All that pull, but hard to find
Even with this great force sucking in anything that comes near it, scientists have had a hard time locating these supermassive black holes. Thick blankets of gas and dust hid the enormous spheres from view.
But recently, NASA's Nuclear Spectroscopic Telescope Array (NuSTAR) mission, launched in 2012, detected highest-energy X-rays penetrating through those clouds of dust.
"Thanks to NuSTAR, for the first time, we have been able to clearly identify these hidden monsters," said George Lansbury of Durham University, lead author of the U.K.-based study. "[black holes] have previously been elusive because of their surrounding cocoons of material."
NuSTAR found five
The scientists found five supermassive black holes after pointing NuSTAR at nine galaxies where these black holes were thought to exist. The areas they searched were extremely active, where black holes were "feasting" on surrounding material.
Not only were the scientists predictions confirmed, the five supermassive black holes were sucking more matter into their cosmic drain than scientists thought.
An artist's concept of NuSTAR mission, an orbiting telescope that detects X-ray energy in space. (NASA / JPL-Caltech)
There are millions more
Scientists now believe there could be millions of supermassive black holes covered by gas and dust. In the ultimate game of hide and seek, researchers will begin searching for any X-ray-producing activity that could lead them to a discovery.
"Although we have only detected five of these hidden supermassive black holes, when we extrapolate our results across the whole universe, then the predicted numbers are huge," Lansbury said in a statement.
Shedding light on dark matter
The black holes may also provide a solution to another scientific secret: dark matter. Dark matter cannot be viewed by any piece of technology, but scientists are certain it's there.
Dark matter is believed to take up 80 per cent of matter in the universe, according to Lansbury's study to be published in The Astrophysical Journal.
By finding more black holes, scientists hope to learn more about why some black holes are obscured while others aren't, said Daniel Stern, the project scientist for NuSTAR. Their discoveries could lead scientists to finally see dark matter, the study said, and would represent a major scientific breakthrough.
