2) The Stelliferous Era (The Stellar Era)
end 1 million to 100 trillion years after the Big Bang (our age)
The primitive times, when the universe was about one million years on the clock and the first stars produces. This era is about 100 trillion last for years which we have only 14 billion years behind us. In the presence of stars are the most important objects in the universe and the source of most of the energy generated in him. The sun is a star - and comparable to the number of stars in the universe by the number of sand grains in a large sand dune, about 10 ^ 23, a one of twenty-three zeros. Most of the energy in this age is produced nuclear fusion inside stars. This process occurs in the sun and will continue for about 7 billion years. Then turn the sun into a red giant so-called its outer shell will about to extend to the Earth's orbit. However, you should not worry about what will be in 7 billion years, the life on earth is already in half the time no longer be possible. With age, the size, brightness and temperature of the sun constantly, so that prevail in 3.5 billion years ago a greenhouse effect on earth that is allowed to evaporate the oceans and the entire biosphere and against the current climate problems, such as a walk cast [Note: the moon will have even earlier still so far from its current path, that the earth's life and destabilizes largely impossible].
It is often said that Sun would be an average star. This is simply wrong: among the 50 nearest stars, the sun is the fourth largest while the average star about a quarter of the mass of the Sun has. Even with a view of the stellar population of the Milky Way is striking that most stars are smaller than our sun. These so-called red dwarfs, there are usually trillion years. The lower limit for stars, the fusion is still operating at only 8% of the solar mass and 1/1.000 their brightness. After their "lifetime" is the sun, as I said, be a red giant, which seems about 100,000 times brighter than the sun today - but the red dwarfs are always about remain the same size and at the end of their days quietly to be white dwarfs. We give an overview of the stars in the universe. About half of the stellar body brown dwarfs, the masses were too easy to get to real stars. These bodies are billions of years and do basically nothing. The other half of the stellar body is composed of stars that burn hydrogen, first, the lightest element, helium by nuclear fusion. Among these stars are red dwarfs, most of all, smaller than our sun. A much smaller proportion has similar characteristics as the sun - and an even smaller part consists of large, massive stars with a much shorter Lifetime than that of the sun. Any star that has at least 8% and a maximum of 800% of the solar mass (and, 99.7% of all stars) is one end as a white dwarf. Our sun will end after her time as a red giant, after having lost about half its mass into space and the rest has shrunk to approximately the size of the earth, so. This future Sun will have a density exceeding that of today's Sun by a factor of a million.
The largest known star, VY Canis Majoris is, with its 30-40 solar masses in a violent supernova border
About 0.3% of the stars is a much more dramatic End experience. These stars explode at the end of their time in a violent supernova - and if such a supernova explodes, it gives two options, then what is left over from the star: a neutron star or a black hole! The former is as dense as the sun, if you just want to compress to 20 kilometers in diameter. The huge pressures and the resulting extremely densely packed neurons, one could almost describe it as a single, giant atomic nucleus. Reduced and compacted to such an extreme object again by a factor of 3 or 4, one obtains a black hole.
Taking into account all relevant factors, it is clear that a galaxy like our own, about 10 trillion years, the formation of stars can be maintained. This is roughly the lifetime of the smallest and most enduring stars, while the 714fachen so far in the universe elapsed time. As a result, it will eventually give in the future, a sharp transition between a universe with stars and a universe without stars. During the 13th Cosmological decade, for a time in which the universe as 10 ^ 13 or 10 trillion years behind it, are the stars seem bright. Although most stars will be small stars in this period it will be at that time hardly darker than it is today: the older a star is, the brighter it seems. But after
be 10 ^ 14 or 100 trillion years burned all the stars have burned out , have their hydrogen
stop and shine. The Milky Way will run out of gas, are formed from which new stars and the star formation process
whole will come to a standstill ...
0 comments:
Post a Comment