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Zyklop
Tuesday, July 13th, 2004, 08:45 PM
This web page is designed to give everyone an idea of what our universe actually looks like. There are nine main maps on this web page, each one approximately ten times the scale of the previous one. The first map shows the nearest stars and then the other maps slowly expand out until we have reached the scale of the entire visible universe.
http://anzwers.org/free/universe/index.html

http://anzwers.org/free/universe/12lys.gif

Nordish
Tuesday, July 13th, 2004, 08:58 PM
Still an incomplete one. But very interesting indeed.

If the Universe isn't constantly expanding at an unfathomable speed I am sure mapping it would be easier.


The Cosmos are an interesting topic.

I've always wondered why black holes haven't meant in end to us all. If the Universe is expanding one should expect that only the edges are somewhat immune from Black holes.

Zyklop
Tuesday, July 13th, 2004, 09:01 PM
Fractals and Cosmology
Recent versions of the inflationary cosmos theory assert that instead of being an expanding ball of fire the universe is a huge growing fractal. It consists of many inflating balls that produce new balls, which in turn produce more balls, ad infinitum. This scenario similarly describes the universe as a self-generating fractal that sprouts other inflationary universes. This constitutes a fundamental change in how the universe is seen as being created and structured. Research Cosmologists at Stanford University are exploring this new theory that the universe went through a stage of inflation and the cosmos became exponentially large within an infinitesimal fraction of a second and they surmise that we could very well soon be saying goodbye to the idea that our universe was a single fireball created in the big bang. The theory is regarded as being general, but looks very promising and leads to very dramatic and interesting consequences in the context of the cosmic chaos blueprint.
http://members.aol.com/SpinChaos/PageFract.html

Zyklop
Tuesday, July 13th, 2004, 09:05 PM
Still an incomplete one.

Why incomplete? The attachment is just one of the maps.

Nordish
Tuesday, July 13th, 2004, 09:11 PM
Why incomplete? The attachment is just one of the maps.

Not incomplete in the normal sense. Incomplete as the Universe is still expanding ad infinitum like you said.

That is to say we haven't peered all the way to the Edge of the Universe.

Orlon
Monday, October 9th, 2006, 10:26 PM
The gravity from black holes decrease with the distance, just as fast as the gravitational influence from stars with equal mass. The gravity is not infinite, it's just great (or, more correctly "dense") enough to give the mass an escape velocity equal to the speed of light, the event horizon actually marks the size the mass would be if the singularity would have an escape velocity of precisely c.

It has been theorised that every galaxy has a enormous black hole in the middle formed as a result from the mass accumulation that created the galaxy. Quasars are only seen in great distances and therefore ages ago, so it's been proposed that the process that gives the quasars their enormous luminosity* is fricition caused by incoming matter as the big black hole pulls it in. Thats the reason we only see them in old light coming from a much younger universe, todays galaxy centres still have black holes, but they've emptied the surrounding space.

(*= wattage in light, one could say)

Feyn
Thursday, November 10th, 2011, 03:58 AM
By now its much more complete and on a new website : http://www.atlasoftheuniverse.com


most people have a completely wrong idea how black holes actually work and what they really are. So i would like to clear up the most common misconceptions and explain how they are created etc. First things first :
A black hole is created when a very massive star (roughly 10+ times the mass of our sun) is at the end of its life and becomes a hypernova. To really explain that let me first explain how stars in general work.
You see in every star we have a fragile balance between 2 forces. A star is made of gar as we all should know. The gravity of the start compresses this gas more and more. From physics classes we know if you compress gas it gets warm (for example if you pump up your bicycle wheel the pump gets warm, try it out). But in a star it gets much warmer, so warm that the hydrogen starts a nuclear reaction that turns it into helium, which is responsible for the light and warmth a start gives of (the reaction, not the helium ^^). So the gravity is the first force, what is the second ? Well the gas is under pressure, and pressurized gas expands outwards. Those 2 forces, the pressure of the gas pressing outwards, and the gravity pressing it inwards form at some point a balance.
That works as long as there is still hydrogen to form into helium, but when the hydrogen runs out the star has a problem. Gravity still compresses inwards, but the outwards pressure is missing, so the star starts to collapse. It gets again hotter and the next level starts, the helium starts turning into carbon. This face happens much faster, so the helium is soon burned out, and the next phase starts and so on.
Now while the hydrogen to helium phase needs ,millions of years the next phases happen very rapidly (i am talking hours-->minutes-->seconds) which turns the star into a nova, a supernova or even a hypernova in which the start literally explodes and all the energy of this nuclear process is freed at once.
Such a supernova can be so bright it outshines the whole galaxy its in for a few hours to days, and a galaxy is made of billions of stars (some have several hundred billion stars, for example the milky way has 200 billion to 400 billion stars astronomers estimate, and its a rather average galaxy, but there are also dwarf galaxies with only a few million stars)
Now back to this balance : the heavier a star is, the more it compresses its gas till this balance is working. That also means its much hotter in the inside, and thus it burns up its fuel much faster (while a typical star like the sun burns 1 billion years or longer a really massive star can burn out in just a few million years). So completely counter intuitive, the bigger a star, the faster it burns out, the fewer life time it has !

So, now we know how a star works in general, lets get to the death. I have already explained it explodes in a nova, supernova or even hypernova, but what happens to the rest ? That depends on how heavy the rest is, so on how much of its mass it blew into space during the nova and how heavy it was to begin with. Most stars become a white dwarf (like our sun will become, and with it roughly 97% of all stars). A white dwarf is the core of the star in which most of the heavy elements are that where in the star to begin with and that elements that got created during the nova. Here the wiki on white dwarfs :

http://en.wikipedia.org/wiki/White_dwarf

As you see its basically extreme dense matter, but still normal matter, only extremely compressed, since no gas pressure can counter the gravity any longer ^^ A typical white dwarf has thew size of the earth, while it has the mass of the sun (the sun in our solar system has 99.9% of the mass of solar system, and all the planets, meteorites, comets etc the rest 0.1%)^^

But what happens when there is even more matter left ? In that case the rest forms what we call a neutron star. From the physics class we know an atom is mostly vacuum. To give you an idea if the atom is a football stadium, the core is a peanut laying in the middle. But in a neutron star the atoms get so compressed that we have the atomic cores directly next to each other and the electrons are absorbed by the protons in the core building neutrons (thus the name neutron star). Here the wiki on neutron stars :

http://en.wikipedia.org/wiki/Neutron_star

A typical neutron star has between 1.3 and 2 times the mass of the sun, but compressed to a ball of 10-20 km diameter. Imagine how dense that is, its nearly unimaginable !

If it has even more mass it collapses to a black hole, perhaps the strangest object in the cosmos. A black hole is defined by its so called event horizon. That is a thought line in space and once you have passed that line even light is too slow to ever get out again. If earth would collapse to a black hole the event horizon would be a few millimeter (afaik 5mm, but donīt quote me on that, i am too lazy right now to do the math ^^)
We donīt really know whats inside the event horizon, since our formulas simply give meaningless results past this line. I know most physicists claim there would be a singularity in the middle of it, where all the mass is concentrated in a mathematical point, but since our formulas donīt make sense i would say thatīs pure guesswork.
But a few more fun facts about black holes : many people think they are this all eating monsters. Well if you get very close to it thatīs correct, BUT a little further away the black hole reacts exactly like the star it once was. Lets say for the sake of the argument the sun would collapse to a black hole, then nothing would happen to the planets. They would do exactly what they did before, orbit the black hole like they did orbit the sun before, nothing has changed. The mass is exactly thew same, so the gravity is exactly the same. This changes only once we get inside the old radius of the sun, and not earlier, and even then it changes slowly. You have to get quite close to really see a difference.
Another fun fact is that there are giant black holes at the core of each galaxy, the one at the core of our galaxy has 4.1 million times the mass of the sun, and our galaxy revolves around it.

Now if you need more info just ask ^^ I hope i could clear up most misconceptions, and let you really understand at least on a basic level what they are and what they do.



Since i guess more people could need this info i will start an extra thread with it, so all the work pays off and is of further use to other people here^^