Astronomers have found one of the oldest stars in the Milky Way
Spanish astronomers announced the discovery of one of the oldest stars in our galaxy. Scientists believe that the object, dubbed J0815 + 4729, was born just 300 million years after the Big Bang, or about 13, 5 billion years ago. For comparison, the age of our sun is only 4, 6 billion years. About his discovery, researchers have shared in the pages of the journal Astrophysical Journal Letters.
"Identification and characterization of these rather rare stars may shed light on the early chemical evolution of our Galaxy, as well as the nature of the appearance of the first stars in the Milky Way" - note the authors of the study.
For their observations, astronomers used spectrographs Space Telescope "Herschel", as well as the Great Canary Telescope, located on the island of La Palma (Spain). These tools allow you to detect the presence of certain chemical elements in the composition of stars by analyzing the wavelengths of light.
Discovered star is located 7,500 light-years away from the field scattered stardust - the halo of the Milky Way, and belongs to a class of dwarfs. The researchers report that the composition of the stars found the minimum amount of iron and calcium. At the same time, the composition contains a high concentration of carbon, which indicates antiquity outdoor light.
"Most chemicals stars J0815 + 4729 are easy. Here there is carbon and calcium. The element iron, usually frequent the stars, in J0815 + 4729 is present in a very meager amount - about one-millionth of the volume that is available for our sun. It is so little, that astronomers can not even calculate it exactly. In these stars all elements heavier than hydrogen and helium found only in the case if the star is very old, one of the first in the universe, and came under the influence of a supernova explosion that occurred somewhere near where the star has formed, "- says astronomer Ian MacDonald of the University of Manchester, is not involved in the study.
They note that although the star of J0815 + 4729 is indeed one of the oldest in the Milky Way, it has a competitor. Earlier Australian team star astronomers found SMSS J0313-6708, which also has a similar carbon rich and poor in metal composition.
The Spanish team will continue to study the open star of them. Researchers want to get a more precise spectral lines of a subject that will help them more accurately classify it, and perhaps even more to learn about our galaxy's history.