Today in my 3rd post I would like to tell you something about two kinds of objects (from universe) which are very bright.
First one is quasar and blazar. As far as i know they are probably same thing but from different angle of view. They are very bright and in middle of them are black holes (if you want to read something about BH then read my second post).
When stars or lot of stuff (dust) around hole starts to accelerate toward the black hole, lot of heat and radiation will be created because particles in high speed will rub againt each other. This will create massive disk around hole. That is called quasar/blazar and it can be even brighter then our own Galaxy!
Second object is Supernova.
It is created in two ways. I will try to explain only the first one because again, i dont really understand how the second works.
Anyway, imagine you have white dwarf (like our sun when it will be few billions years older). It is object which has such mass like our sun but it is big like Earth. It is shining even that termonuclear reaction does not occur anymore. After some time it will turn to black (cold) dwarf. But if this dwarf gains some mass again and heat inside core will be high enough to create another round of reaction it will violently explode! Picture on the left shows galaxy and that “little” point is actually supernova. It does not shine long time, only for weeks or months.
So those are the two bright objects in our universe. I hope i did not miss something important.
Btw. thanks to people who liked my posts, i really appreciate that.
PS. next time I will probably move to something on the earth!
P.1: Quasar. (2015, March 2). In Wikipedia, The Free Encyclopedia. Retrieved 12:47, March 20, 2015, from http://en.wikipedia.org/w/index.php?title=Quasar&oldid=649527988
P.2: Supernova. (2015, March 17). In Wikipedia, The Free Encyclopedia. Retrieved 12:47, March 20, 2015, from http://en.wikipedia.org/w/index.php?title=Supernova&oldid=651800657
this is my second post. I would like to say something about my most favourite topic: Black holes. I hope that there won´t be any mistakes so I will not go deep and more complicated stuff.
Black holes are universal objects as you probably already know. Important thing is their size. If you know something about white/black dwarfs and neutron stars you could easily get to right answer about how big are black holes.
You see I said something about dwarfs and neutron STARS. Right, stars. There are not really kind of stars but all of these three objects come from stars like our own Sun!
I will probably make another post for only stars so I will write this short. When gravitation pulls lot of dust from universe together it will have so huge gravitation (like our Sun) that termonuclear reaction will occur. (Jupiter is almost so huge that he would be another small sun if little bigger) This reaction will be able to keep star from falling into itself by gravity. But when fuel (H,He…) runs out it will crush itself under gravity. If it was small white dwarf will be next stage. (That will happen to sun). If gravity pull is very huge electrons won´t be able to hold the force and neutron star will appear (made of neutrons). If it is even larger and strong interaction won´t be enough strong black hole will born!
In black hole there is actually no force to hold it and it will fall into singularity! That is point infinitly dense and infinitly small.
Particles have gravitational pull on other particles. When there is lot of particles, gravitation is very strong and it will start to bend spacetime(P.1).
(Sun does that and stars behind seems to appear somewhere else than they are.) Black holes have such strong pull that even light can not escape, that is why they are black (no light comes to your eye).
Around black hole is event horizont. That is circle which is edge of black hole. Light circles around it. It can not escape but it wont be either sucked by hole.
Long time it was thought that black holes can not decay particles but Stephen Hawking actually came up with Hawking radiation. On this topic I will have to learn something more because I dont really understand how it works. Anyway black hole is actually radiating (lossing mass) and at one point it will explode when strong nuclear force will be again able to fight gravitation. Can happen after 10^66 years.
Surely I forgot to say something but you can ask me in comments.
Please comment this post if there are any mistakes!
Btw. I highly recommend to read The brief history of time by S. Hawking
p.1: Spacetime. (2015, March 5). In Wikipedia, The Free Encyclopedia. Retrieved 18:24, March 19, 2015, from http://en.wikipedia.org/w/index.php?title=Spacetime&oldid=649931558