What is a black hole?
When giant stars (stars much bigger than our sun) die, they don’t do so quietly. They explode. This explosion is called a supernova. During a supernova, all the matter of the previously living star is squeezed into a dot tinier than the head of a pin (can you imagine something larger than the sun fitting into a dot that small!).
This dot is a black hole. It may be tiny, but it is deadly. Its gravity is so strong that it can swallow an entire star. Black holes suck up anything and everything that gets near it. Nothing that gets close to it can escape it, not even light - which is the fastest thing in the universe.
Is there a black hole close to Earth?
Yes and no. Every galaxy has one supermassive black hole. Our galaxy, the Milky Way does too - Sagittarius A* (pronounced Sagittarius A Star). Fortunately, this local black hole of ours is 26,000 light-years away. So, no danger of Earth getting sucked in there.
A few days ago, NASA released the first-ever image of Sagittarius A*. This image was taken using a very fancy telescope named Event Horizon Telescope (EHT) and took many years to capture.
Umm…what am I looking at?
The bright orange ring circling the black centre is made up of gases and other matter being pulled in by the black hole’s gravity.
The black centre you see is the area of its gravity pull. The actual black hole is tinier than a dot, so we can’t see that.
The EHT scientists are now hard at work trying to figure out how to capture a video of Sagittarius A*.
