Astronomers from the Australian National University reported the discovery of the oldest star in the known Universe. The object belongs to the class of so-called red giants and received a very complicated and long name SMSS J160540.18-144323.1. Interestingly, the star is on the edge of our galaxy, the milky Way, approximately 35,000 light-years from Earth. That this star is very old, the scientists said the study, which showed that this light has a very low content of metals, among all the other known stars.
The oldest star in the Universe
According to scientists, this star belongs to the second generation of starswhich formed soon (in cosmic terms) after the Universe’s birth 13.8 billion years ago.
This is incredibly old star, which probably formed only a few hundred million years after the Big Bang, has the level of iron in 1.5 million times lower than that of our Sun. It’s like a drop of water in the Olympic pool, says Tomas Nordlander, one of the authors of the study.
How did the stars?
The researchers explain that the very first stars in the Universe consisted only of light elements such as hydrogen and helium. They were practically no metals and especially iron, since these elements to the birth of the first stars had not yet formed.
Scientists say the first stars were very large and short-lived. In the course of thermonuclear reactions in their bowels the atoms of light elements together into heavier elements. As soon as the life of these stars came to an end, they explode very bright supernova, scattering heavy elements across the cosmos.
With the formation of new stars heavier elements were drawn towards them under the influence of very powerful forces of gravity. At the end of their life cycles, these stars, too, exploded. The new born and so generation after generation. For example, it is believed that our Sun consists of elements 100, 000 generations of stars that existed before him.
Scientists suggest that the star SMSS J160540.18-144323.1 formed after the explosion one of the first stars in the Universe. Maybe she had a very tiny mass for stars of the time and was only 10 times more massive than our Sun. Probably the explosion of a star at the end of her life’s journey was so weak that the star has not died entirely, and left behind a naked core. A large part of the ejected matter of the former star (heavy and light chemical elements) dropped back to this core. The remaining matter formed a new star, the same one that was discovered at the present time. Astronomers are going to explore it more closely to get a better idea about the stars that existed in the early Universe.
As mentioned above, the oldest discovered star is in the phase of the so-called red giant. This means that she is dying — her last reserves of hydrogen to continue thermonuclear reactions. By the way, our Sun in the future, in about 5 billion years, met the same fate. When that happens, all life on Earth (if the planet yet will be something alive) will be destroyed.