Friday 7 March 2014

Star slightly younger than the Universe

Australian astronomers, during the project mapping parts of the southern sky, discovered Star SM0313, whose age is estimated at about 13.6 billion years, only a few hundred million years younger than the age of the Universe.


One of the very important information about the objects in the universe that spectroscopy reveals is their age. Australian astronomers , during the project mapping parts of the southern sky discovered Star SM0313 , located less than 2 kiloparseka of the solar system ( the diameter of our galaxy , the Milky Way is about 30 kiloparseka ) . After precision spectroscopic observations 6.5 meter Magellan telescope in Chile , and the stars age is estimated at about 13.6 billion years. Only a few hundred million years younger than the age of the Universe .
Indicator of great age, and the stars is that its range is such that points to the almost complete absence of elements heavier than hydrogen and helium . For example, the proportion of iron in the composition of these stars is ten million times smaller than the fraction of iron in the composition of the Sun . This points to the fact that , at the time when these stars formed in the universe was much less heavy elements than today . How heavy elements are formed in the evolution of stars and are dispersed throughout the universe in supernova explosions , this is an indicator of the extreme age of the stars SM0313.


The process of determining the chemical composition of the stars on the basis of the spectrum and its age on the basis of chemical composition is the result of an extremely successful and detailed theoretical analysis which started greats such as astrophysics S.Čandrasekar , Eddington , E. Salpeter and others. However , believe it or not , this star is not made ​​of intact gas . The share of heavy metals is higher than that which arose in the big bang , so currently we think that these stars formed from material which, upon reaching the stage of a supernova , threw the first stars , known as Population III . Population III stars were made ​​up entirely of hydrogen, helium and lithium, elements that were created in the Big Bang . They , however , have not yet been directly detected .
Evolution of stars, from lighter elements are formed heavier , which are processes in the final stages of the evolution of the stars were scattered into the surrounding interstellar medium . From it are gradually emerged a new star that were richer and richer in heavy elements . Sun , Earth and life as we know it here would not be able to occur without this process of " cosmic recycling . "
Direct detection of population III stars will be one of the main tasks of the James Webb Space Telescope ( JWST ) . Understanding the process of evolution of the first stars is extremely important for the theory of the formation and evolution of galaxies , as well as for better understanding of cosmological processes , such as zoning .

2 comments:

  1. Surprising, surely!
    On a 1-100 scale, stars started aggregating only 3 years after matter having come into existence (of the cyclic pulsations of The Universe) !

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  2. We all have a commitment towards our kids in helping them accomplish and exceed Essay Thinker expectations in their school studies.

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