What is black hole ?
A black hole is a place in space where gravity pulls so much that even light can not get out . The gravity is so strong because matter has been squeezed into a tiny space .
I want to start with how do we know black holes even exists ?
Einstein explain the universe through his theory of general relativity . The theory not only described the relationship between space , time , gravity and matter , it opened the door to the theoretical possibility of a particularly mind-boggling phenomenon that would eventually be called black holes .
Today essentially we know that black holes exist because even though they don’t emit light they do have lots of gravity .
We can find out exactly how much gravity an object exerts by measuring how fast something else orbits around it .
We have some questions about black hole for example :
1. How big are black holes ?
2. What do black hole form ?
3. Could a black hole destroy Earth ?
Black holes can be big or small . It's unbelievable to know the smallest black holes are as small as one atom but have the mass of a large mountain . Scientists think the smallest black holes formed when the universe began and supermassive black holes were made at the same time as the galaxy they are in . Black holes don't go around in space eating stars , moons and planets . Earth will not fall into a black hole because no black hole is close enough to the solar system for Earth to do that .
Black holes are very incredible and mysterious object for those interested physics and astronomy . This is a very short review article then hope you enjoy .
Sources : NASA - History - Popular Mechanics
