Universe or the beginning. Passed 300,000 years after the Big Bang until now and the temperature dropped enough to talk about atoms, atoms of hydrogen, helium and some lithium. It was there and a lot of light, light that the detective today, as radiation relicte, famous background radiation of 3 K. The radius of curvature of the universe is only 15,000,000 days light. A spectacular and mysterious universe, which only in recent years have begun to “see” with sondelor space. One of them, WMAP, we sent pictures of spectacular (details on numbers 9-10/2001 and 1-2/2004). We’ll talk to one of the future about this early universe, but today we want to take care of the stars of … 

  
We would be hard to imagine a desert sky of stars, as it was in the early Universe. A sad Univers … Actually star appearance remains a fertile ground for hypotheses, while we see a star directly created from primordial matter. We now know that the universe is 13.7 billion years old (age calculated by scientists based on data provided by WMAP). We know that age and older planets in the universe: about 12.7 billion years. So somewhere in the range of 1 billion years after the birth of the world, the first stars appeared. What? How?

Answers to these questions are not easy short of time. We need, in addition to theoretical models, data derived from observation. And just in the area of astronomical observations, which you place in the physics experiment, the available data are almost zero. To explain a little situation there today.

I said in opening this article as the beginning the universe was composed of more hydrogen and some traces of light elements such as lithium and heli. Heavier elements came later, being made in the middle of the first stars. Here is our first difficulty. Looking in the Universe interstellar clouds of primordial matter, which should not contain heavy elements. The way we have now is to analyze the light that comes from our most distant galaxies. And see that there exist material produced in stars, so I have something to do with primordial matter. We could think that we’ll find somewhere outside galaxies, in the form of agglomerations of intergalactic gas. Only that it did not search results. Basically, it was light we analyzed comes from the most distant heavenly bodies: quasarii. It has crossed many intergalactic clouds to get to us. But it failed measurements in the beginning of the discovery material universe. In clouds of intergalactic heavy elements already exist!

Issue
Here’s a complicated situation. We have pretty good information about the universe 300,000 years after the Big Bang. But I know not how the first stars showed, nor how they formed. We do not know because, I repeat, we can see directly now. To find answers, even hypothetical, scientists have provided a very powerful tool: mathematical modeling, that is, using equations to simulate the evolution of systems.

Before presenting the results reached in the present, we believe that it is useful to tell something about the difficulties that had to be overcome.

When a star is formed it is necessary to have a cloud of material that compress due to gravity. No problem. Images transmitted by WMAP shows that since the beginning there was fluctuation in the universe of initial density of matter, so aparusera already huge agglomerations.

We have still a little problem. When condense interstellar cloud temperature increases it very much (the law is valid for any gas). That means we have increased the average speed of gas components, which should cancel the process of compression. Nowadays this surplus energy is discharged through water molecules (about this story in the number 3 / 2004 of our magazine) and carbon monoxide, no component in those days of top … We can think of heat as the evacuation was done by molecular hydrogen. But molecular hydrogen is formed with interstellar dust, by way of condensation. And interstellar dust does not exist in those times. Here is how we revolve around the same issues, which responded, resulting from the modeling could be that still may occur in the absence of star and heavier elements, with a very inefficient mechanism. I mean by a great waste of material. And there must be something … must have what physicists call darksome matter, a matter strange, now, at the universe, make the Universe expansion is accelerated.

Modeling
How can show such a scenario? To answer we have used modeling performed by researchers Greg Bryan, from MIT, Michael Norman, Univestitatea of California-San Diego, and Richard Larson, of Yale University.

The process by which were born the first stars began relatively soon after the Big Bang, somewhere in the range between 13 million and 100 million years after the Big Bang. Initially were small fluctuation in the density of the Universe. In 100 million years after the appearance of dark side of the material universe began to concentrate in areas where density was higher, drawing away the hydrogen atoms. A small part of them were nearly so much, that began to form molecules, thus taking high birth molecular cloud with a diameter of between 10 and 1000 parsec (one parsec is equal to 3.6215 light years, or, in kilometers, a parsec is equal to 3.0856 x 1013 km). Broad has been ordered to mass thousand suns. In the next stage begins gravitational compression of the gas agglomerations. After a few million years, temperature and pressure of the molecular cloud reach values large enough to trigger thermonuclear reactions. The first star. Modeling shows a table for it between 100 and 250 solar masses. A star really huge. But huge stars burn very quickly. At the core of their thermonuclear reactions take place at a pace downright hellish. And it happens that the big stars live a little, very little, if we compared to our sun. Huge exploding stars and quickly throw the new matter in the universe, in which we find the hardest, which makes it easy birth of new Astra and the first planet. But the explosion is not discharging anything less than half the initial mass star, the rest are crowded in the death star, forming a black hole supermasiva. The above might explain the black holes at the center of galaxies, which we talked about the number 3 / 2004 of our journal.

This was a possible scenario of the formation of first stars, which we very much simplified. Give answers to many questions, but do not know yet if those are correct. Probably in the years to come we will have more detailed models and more accurate. But whatever the mathematical models would be required observation verification. Our tools today can not help but we have hopes for the future. Unless something changes in the river at NASA in coming years (specifically in 2009) will be released in space NGST (Next Generation Space Telescope), a wonderful tool, with a mirror 8 meters (comparable to the 2.4 Hubble’s me), we will provide detailed images of galaxies as they were now many billions of years (for further details please refer to the number 3 / 2002 of our magazine). Then we will confirm or rule out the scenario outlined above.

On something else bothering me. Say that the old planet in the universe was only one billion years after the Big Bang. Planets appeared very quickly in the Universe. It may have appeared and life in a young universe?