Scientists discover 13 billion year old star with loss mass and metal content
New Delhi : Here's news for avid sky watchers. Astronomers have discovered the one of the oldest stars in the Universe. They say that the star is 9 billion years older than the Sun.
While another new research published in the Astrophysical journal suggest that astronomers have found 13.5 billion-year-old star in an unusual place. Such kind of stars are usually seen in distant areas of the Milky Way galaxy but this particular star was found in a region known as the “thin disk”, where the Sun is also present. The estimated age of the star also suggest the age of our galactic neighbourhood by around 3 billion years than actually assumed.
Researchers say that the first stars of the Universe were formed of only hydrogen, helium and some lithium. When these early stars died out in explosions known as “supernovae”, they emitted large clouds of dust and gas consisting of heavier metals. These clouds, also known as “nebulae”, gave birth to the next generation of stars with more heavy metals. The following generations of stars had a greater number and quantity of heavy metals, produced through the cycles of birth and death of stars. By studying the composition of stars, scientists can deduce the ages of these stars.
For now, the newly-discovered star is considered as a part of two stars that revolve around a common point, also known as a binary star system. The star has low mass and low metal content. Also, it holds the record for the lowest complement of heavy metals also known as the star’s metallicity. It has metallicity similar to that of Mercury while the Sun has as much as 14 times that of Jupiter.
Now, scientists believe that there could be some more such stars hidden somewhere in the galaxy. Some of them may be older while others might have just taken birth.