This week I attended The Secret Science Club to hear Caleb Scharf, the director of the Astrobiology Center at Columbia University, talk about black holes.
I discovered some mind-blowing facts about black holes that I didn't know: I used to think they were just these mysterious destructive forces in the universe that vacuumed up matter.
While this is partly true, black holes are also very dynamic. They spit out huge energy beams, shaping the universe around them, and may have been necessary for creating life on Earth.
They were actually the brainchild of John Mitchell.
I always attributed the discovery of black holes to Einstein.
While Einstein did revive the theory in 1916, John Mitchell actually thought of it first, back in 1783. The idea didn't go anywhere, though, because he didn't know what to do with it.
Mitchell started to develop the theory of black holes when he accepted Newton’s theory that light consists of small material particles, called photons. He wondered how the movement of these light particles is impacted by the gravitational pull of the star they are escaping, and what would happen to these particles if the gravitational pull was so strong that light could not escape.
Mitchell is also the founder of modern seismology, when he suggested earthquakes spread out as waves through the earth.
They literally pull the space around them.
Last night Scharf said to think of space as a rubber sheet. Think of the mass of a planet as a ball pushing down on the rubber sheet. The sheet of space becomes distorted and no longer has straight lines. This creates a gravitational pull, and explains why planets orbit the sun.
Space can become increasingly distorted as an object's mass gets larger. This further distortion increases gravity and accelerates orbits, pulling anything around the object in faster and faster.
For example, the orbit of mercury around the sun is 30 miles per second, but the orbit of the stars close to the black hole at the center of our galaxy is 3,000 miles per second.
If this pull is strong enough, the orbiting object gets pulled into the larger object.
They come in different flavors.
We usually think of a black hole as just one kind, but astronomers have recently noticed that they come in different variations.
There are spinning black holes, electrical black holes, and black holes that do both. Regular black holes grow by swallowing matter, and spinning black holes are formed by the merging of two of them.
These black holes put out even more energy, because of their increased distortion of space. They make it impossible for matter near them to stand still or orbit slowly. A charged, spinning black hole can act as a particle accelerator.
One black hole called GRS 1915+105, about 35,000 light-years from Earth, is spinning more than 950 times per second.
See the rest of the story at Business Insider