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找到一颗比宇宙还老的恒星?

There are many theories about the origin of the universe, but as of 2019, it is a theory that the universe was created by the Big Bang, which occurred 13.8 billion years ago, and that the star was formed by material produced during the violent explosion at that time. However, the estimated age of the star HD140283, also known as Methuselah, 200 light-years away from Earth is more than 14 billion years, contradicting the theory that the universe began 13.8 billion years ago.

Methuselah is said to have lived to the age of 969 as a character in the Genesis of the Old Testament. Among the celestial bodies known as HD140283 with the name Methuselah, the oldest star was originally estimated to be 16 billion years old. Obviously, due to the contradiction that stars older than the universe exist, many astronomy researchers have re-measured. Pennsylvania State University astronomer Howard Bond is one of them.

He and his collaborative research team first verified in detail the 11 sets of data observed by the Hubble Space Telescope between 2003 and 2011, and confirmed the distance between the Earth and HD140283. The reason is that the age of a star is mainly calculated by examining the material components that make up the star through light spectrum analysis. Therefore, if the distance between the earth and the object is wrong, the analysis will also be affected.

The team also examined the composition of the substances that make up HD140283. As a result, it was found that the HD140283 had more oxygen than expected. Based on this, the HD140283 age was calculated and succeeded in reducing the age of HD140283 by 1.5 billion years. The research team predicted the age of HD140283 to be 14.46 billion years. However, even this does not change that it is older than 13.8 billion years, the age of the universe.

Subsequently, the research team continued to follow up, reducing the age of HD140283 to 14.27 billion years. Nevertheless, it was still investigated as being older than the age of the universe. Of course, as the result was that the error due to the uncertainty of the amount of oxygen was about 700 million to 800 million years, it can be regarded as a little younger than the age of the universe if it is within the error range. Because of this, the research team concluded that it could be said that, given the uncertainty of the assumption, an age of HD140283 that was consistent with the age of the universe could be derived.

While the riddle of the first star in the universe has been solved, a new riddle is also emerging. This is because a recent study has raised the possibility that the universe age of 13.8 billion years itself is an error. The original universe age of 13.8 billion years was calculated from the expansion rate of the universe expressed by the Hubble constant. Specifically, it is expanding at 67.74 km per second per 1 megaparsec, which is 3.26 million light years.

However, the research team of Hiro Komatsu, a professor of physics at the University of Texas, published a paper that the Hubble constant was found to be 82.4 in the results of precise space observations using a gravity lens this year. Assuming that the universe is expanding at a rate of 82.4 km per second per megaparsec, the age of the universe could be significantly reduced from 13.8 billion years to 2.4 billion years younger than 11.4 billion years.

If the universe was 11.4 billion years old, the question of the existence of stars older than the universe could remain unsolved because it is much younger than the estimated 14.27 billion years of HD140283. One expert on this issue pointed out that when looking back at the history of science, the truth is often intermediate (combined) when two contradictions appear.

The research team is thinking that a mystery that has not yet been elucidated, such as the intensity of dark energy, which is said to be the driving force that expands the universe, gives an error of billions of years to the research results. He expressed the view that further progress on cosmology is needed to solve the cosmic riddle. Related information can be found here .