More About Black Holes
What is a black hole and where can I buy one? To answer the last question first, when I find out I'll let you know, but I bet it will be the Department of Defense. People have predicted tiny versions of black holes will someday be used as weapons. Boy I hope not, because after you read this article and find out exactly how powerful a black hole is you will understand my fear. There is another use for tiny black holes being talked about and it is using them to power spacecraft. This would give a craft just about unlimited energy. It might even enable a craft to fly far faster than the speed of light giving us the chance to explore places in the universe never thought possible. The distances in space are a barrier to humans exploring. Even the distances in our solar system prevent human space travel. Some say it is not the distance which is the problem, but the speed at which we travel today. Either way we have a problem, and black holes could be the answer and the problem.
This brings me to the Large Hadron Collider which keeps getting updated and more powerful. It has gotten to the point where some say we could create tiny black holes by accident and they could get out of hand and eventually swallow the planet. Some scientists don’t deny they might make some tiny black holes, but they tell us there is nothing to worry about since they will only last a micro second. I don’t know how others feel about this, but it doesn’t make me happy to hear this. I know just by looking at history how many times scientists have been wrong and an error in this area could be deadly. It makes me think some of this research is to develop black holes on purpose to try and use them for what I said above and maybe for other things. If we could hurl a black hole at an asteroid which was going to hit us would this solve the problem or create a bigger one for us? Black holes are just too dangerous to experiment with on this planet. Perhaps someday, way out in space, far from earth they might do this, but it should not be done on or near the planet.
It is believed black holes come from collapsed stars. The theory is eventually a star will use up the fuel that keeps it burning. The gravitational forces which were kept at bay by the active star now force it to collapse upon itself. As it does this, heat is created and the star get so hot it explodes. The exploding star is a supernova and some of its mass is blown away, but what is left is compressed further and so massive the gravitational field stops anything from escaping, including light. Since you cannot see any light coming from it, it looks like a black spot in space.
Black holes seem to come in different sizes. There are stellar black holes, these are the ones that come from collapsed stars and there are also black holes that contain the mass of billions of stars and there are the tiny black holes. Galaxies that emit far more energy than normal are known as active galaxies. There are several types of active galaxies: Seyferts, quasars, and blazars. Most scientists believe even though these types look very different to us, they are really all the same thing viewed from different directions! Quasars are active galaxies which are all very, very, far away from us. Some of the quasars we have seen so far are 15 billion light-years away! Blazars are very bright in the radio band, which results from looking directly down a jet which is emitting in synchrotron radiation. On the other hand, if the jet is not pointing toward you at all, and the dusty disk of material which lies in the plane of the galaxy is in the way, you would see just what we see from the Seyferts. By measuring their redshifts, we find that Seyferts are much closer to us than quasars or blazars. It is believed these objects are the home of massive black holes. They could be billions of times the size of a stellar black hole as I stated before.
Let’s examine the different types of objects that contain these super massive holes and see what their differences are.
Seyferts are named after Carl Seyfert an astronomer who took photographs of them in the 1940s. They are spiral galaxies with a bizarre object in the center. The center varies in brightness over a period of months. They are less than 1 parsec in size. A parsec is defined as the distance from the Sun which would result in a parallax of 1 second of arc as seen from Earth. This is about 2.6 light years. In later years radio telescopes examined Seyferts and found structures on opposite sides of the galaxies and a tiny source of radio emission at the nucleus. There are electrons being shot out in narrow beams. In summary this galaxy has jets, lobes and a very hot spot where the jets hit the interstellar medium.
Quasars are Seyfert Galaxies and Radio Galaxies, where the nucleus outshines all the stars by an outstanding factor of 10 to 1000 times. Quasars seem to be further away than ordinary Seyfert galaxies. If this is true than maybe they are not all the same.
Blazars are believed to a subclass of Active Galactic Nuclei, but their jets are pointed toward Earth. They emit the widest range of frequencies. An object cannot be classified as a Blazar unless it has one of the following properties:
1. A high radio brightness accompanied by flatness of the radio spectrum
2. High optical polarization
3. Strong optical variability on a very short time scale which is less than a few days
Tiny black holes may be formed by mass being compressed into a very small package. Suppose our sun was compressed into the size of a baseball, you would now have a tiny black hole. I have always thought maybe relatively small pieces of matter that were shot out from a star were pulled together by gravity and formed tiny black holes, but I'm no scientist.
So how do we know black holes exist if we can't see them? Sometimes we are lucky enough to see the matter flowing into them. We can also detect X-ray emissions caused by the superheating of matter falling into the black hole. If a binary system is found with a black hole, it makes it easier to detect because of matter being drawn off the companion star. Recently a photo has been taken of a black hole proving once and for all they truly exist.