Black holes are places in space where matter is dense and gravitational forces are extremely strong. Black holes can be thought of as pits, and any object close to the pit is pulled into it. Light cannot even escape a black hole.
What are Black Holes?
Most black holes are formed when stars collapse and die. Stars use fuel during their lifetimes, and they reach the end of their lives as their fuel is burned. Once the hydrogen that fuels a star is quickly used up, the star starts to use helium as fuel. When there is no more fuel, the star collapses.
When a star dies, it can explode and send material off into space. During the collapse, the core of star begins to compress to its gravitational center. The core continues to compress and becomes denser over time. This dense object, which pulls all materials towards it, is now a black hole.
Supermassive black holes are considered the largest kind of black hole. Scientists think that this kind of black hole may be formed differently than stellar black holes, which are formed from dying stars. These black holes may have just grown over time, or supermassive black holes may be the result of black hole combinations after collisions. Supermassive black holes are found more often at the center of galaxies, and some scientists think this type of black hole was formed at the same time the galaxy was formed.
How Do Black Holes Work?
Black holes use gravitation pulls to consume everything that closely passes by them. Black holes can consume light, gas, dust, and other objects in space. As the black hole pulls objects and light into its center, it gains more size and mass.
Since black holes are formed from the burning, exploding, and movement of dying stars, black holes tend to spin in space. When you see images of light and matter being pulled into a black hole, you will see the matter swirling around a black center.
Where Are They Found?
Scientists can only see black holes by noticing light and objects pulled towards a single point. In a sense, they notice the black hole’s gravity before they notice the black hole.
Small black holes can be found wherever a collapsed star is found. Smaller black holes are hard to spot, and they tend to be isolated. Scientists guess that there are as many as ten million to a billion black holes that are small and isolated in nature.
Supermassive black holes are different because they primarily exist at the center of galaxies. In fact, scientists estimate that nearly all galaxies have a supermassive black hole at the center. Even our galaxy is likely to have one.
Famous Black Holes?
- NGC 4889: One known supermassive black hole is located at the center of NGC 4889, which is found in the Coma Cluster. This black hole is currently dormant, but it could begin consuming light and objects at any moment. The black hole at the center of this galaxy is also one of the largest ever discovered.
- Sagittarius A*: A super massive block hole which is at the centre of the Milky Way Galaxy. This black hole contains the mass of 4 million suns.
Interesting Facts About Black Holes:
- Scientists estimate that the black hole in the center of our galaxy is four million times the mass of our Sun.
- The black hole at the center of the Milky Way Galaxy is called Sagittarius A. It is about 27,000 light-years away from the Earth.
- V616 Monocerotis is the closest black hole to Earth. It is 3,000 light-years away.
- Black holes warp time and space, so a clock in a black hole will appear to run progressively slower to those standing outside the black hole.
- Cygnus X-1 is the first black hole discovered and accepted by astronomers.
- Our Sun is not big enough to create a black hole when it collapses.
- Black holes emit radiation as they consume materials. The radiation can help scientists locate them.
- Objects that pass black holes are not automatically consumed. The object has to get close to the black hole to be overcome by the gravitational pull.
- Black holes grow in size and density throughout their lives
- Scientists cannot directly see black holes. They have to look at the objects being pulled around the holes.
- All matter in a black hole is compressed to a point called the “singularity.”
- It is impossible to see any event take place after a point in the black hole called the “event horizon.”
- When something falls into a black hole, it can never come back out.
- John Archibald Wheeler coined the term “black hole” in the 1960s.