“Something would have to travel faster than the speed of light to escape and it can’t,” Reynolds said.
What are the types of black holes?
There are three types of black holes. The smaller ones are stellar black holes that form when stars much larger than our sun explode.
These black holes typically have a mass 10 to 24 times the mass of the sun, and are typically 26 miles in diameter, roughly the same distance between downtown Detroit and Pontiac.
Reynolds said these black holes are common, with millions of them scattered throughout the Milky Way.
Then there are the intermediate-mass black holes that can hold the mass of 100 to 10,000 suns. Some scientists believe that intermediate black holes form when multiple stellar black holes collide.
Supermassive black holes, like Sagittarius A*, reside at the center of most galaxies and are heavier with masses ranging from millions to billions of solar masses.
Scientists estimate the radius of Sagittarius A* to be around 14 million miles.
Scientists are still puzzled by the size of supermassive black holes, but Reynolds said one theory is that they have been feeding off what has been around them for billions of years.
What do black holes look like?
Black holes are a large amount of mass in a small space. When things enter the black hole, they are torn apart and a massive amount of energy is released called the event horizon.
The event horizon is the bright donut surrounding the black center of the images. When the center of the black hole is not rotating, its shape will be a sphere but there is no physical surface.
If the center rotates, the black hole’s event horizon will change. Reynolds said it widens and flattens at the poles.
“Basically, all black holes spin,” Reynolds said.
How did you find a supermassive black hole?
Astronomers predicted there was a supermassive black hole, but Reynolds said finding Sagittarius A* wasn’t easy.
According to Reynolds, the best place to start looking for a supermassive black hole is in the center of a galaxy. This is because the greatest density of stars is towards the center.
“A really smart place to point your telescope is where the most objects are,” Reynolds said.
Despite their namesake and ability to swallow light, black holes are actually some of the brightest objects in space.
The materials that black holes engulf, like jagged stars, are heated and spewed out with ridiculous pressure – the flares can be seen across the universe.
Reynolds said the next step is to observe the wavelengths of flares coming out of a supermassive black hole. Sagittarius A* is known for solar flares that occur once or twice a day.
Reynolds said it took a massive team of scientists tuning telescopes to shorter wavelengths for two decades to see past the haze that had been previously captured. The result? Direct images of plasma orbiting a black hole.
How far from Earth are these supermassive black holes?
Sagittarius A* lies 27,000 light-years from Earth and is the only supermassive black hole in our galaxy. Other supermassive black hole scientists have images of M87*, and it is much larger than Sagittarius A*.
M87* is wreaking havoc in a galaxy 55 million light-years from Earth and is one of the largest known black holes. This supermassive black hole is 1,000 times more massive than Sagittarius A*, but due to their distance from Earth, the two black holes look alike in the sky.