Blackholes

Researched by : Alex Gabrielli
 * [[image:blackhole2.jpg width="203" height="212" align="right"]]Black Holes: Discovering the Mystery of Our Universe’s Darkest Secrets**

There have been many mysteries about black holes that leave scientists baffled. Questions go unanswered: how long are black holes? Is it possible to go in a black hole without being crushed and burned? Is [|time travel] possible? How do we see black holes? Although mankind still hasn’t figured out all of the mysteries about black holes this project will try to answer most of them.

When a star ten times the mass of our sun, “dies” it creates a brilliant explosion of light know as a [|supernova]. After the supernova only the core of the dead star is left. The force of the core collapsing is so powerful that it crushes the atoms. The negatively charged electrons go inside the center nucleus of the atoms while combining with positively charged protons which turns all of the matter into dense neutrons that don’t have an electric charge. The core shrinks to about the size of a city and turns into a [|neutron star]. Another mystery is how we know if black holes are really there. Black holes are not visible to the human eye because any light that goes too close to the black hole will be sucked in. That is what makes black holes appear to be invisible because humans are not capable of seeing without light. When the black hole spins it sends pulses of radiation throughout the area. When these pulses go by Earth the scientists use a series of telescopes to record the pulses. Scientists call these pulses [|pulsars]. That is how we detect the black holes and find out how rapid it spins. If the star is about ten times bigger than our sun the impact would be so great that even it’s neutrons will get crushed. The core will get so dense that not even the fastest object known to man (light) can escape its gravity.
 * How Black Holes Are Created**

If any object gets close enough to the black whole then the only way to is escape it’s powerful pull is to go as fast as the escape velocity (usually faster than the speed of light) which nothing else in the universe can achieve.

Many people think of black holes as a hole that sucks in everything around it of course not all of this is true. A black hole only sucks objects that are past the event horizon. The event horizon is the point where the gravity of the black hole can affect an object close enough to it. Many people think that a black hole pulls in objects in a straight line but it actually twists so the object will be forced to spin around the black hole until they get sucked in. When a star gets close enough to the black hole then the star will slowly turn into a curved ellipse until the whole thing gets sucked in.
 * How black holes work**

If you were watching it you might be able to see the light bend. It is surrounded by a disk called the [|accretion disk]. The closer you get to the black hole the hotter it gets. The gas close to the center of the disk is about as hot as one hundred eighty million degrees Fahrenheit (one hundred million degrees Celsius). When matter is close enough to the black holes it gets so hot that it gives off x-rays then it gets pulled inward by the tremendous force of the black holes gravity.

A black hole is shaped like a cylinder and is surrounded by a molecular ring (a dense ring of gas and dust). A black hole can be compared to as a whirlpool or tornado. Although a black hole is small it can weigh up to a billion solar masses. A black hole has a strong magnetic field that jets particles and radiation out from its poles. The jets billow out and form a lobe when they meet intergalactic gas. The intergalactic gas shoots out radio waves while the jet of particles and radiation from the really hot matter slams into it. Some black holes blow large bubbles of gas when strong jets coming from the magnetic poles of the black hole create a glowing shell where it meets surrounding gas. Black holes can spin faster than 642 times a second. A black hole usually has an orbiting star around it called a binary companion. The more gas the black hole consumes the larger it gets. One of the most common mysteries about black holes is if two black holes are close together it could generate a worm hole that could make a rip in the [|time/space continuum] that would allow time travel to be possible. If this is true it could change the black holes and everything around it. It might be possible that the black holes could become unstable and create an explosion that could be like a supernova. Another one is it might be possible that if you could survive going through a black hole that it might take you to a different galaxy or universe. It may even be able to transport matter from one place to another in a split second. This may result in people being able to transport anywhere in the universe but it is very unlikely and unfortunately humans are not capable of going that fast. In a reverse of time a black hole is known as a [|white hole]. Unlike a black hole which can only suck in objects a white hole can only spit objects out. In reality it is impossible to create a white hole just like it is impossible to destroy a black hole.
 * Physical Characteristics of a Black Hole**

Bibliography

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