11/7/2018 One of the oldest stars in the universe hiding silently in Winter Street about 2000 light years from the…
11/7/2018 One of the oldest stars in the universe hiding silently in Winter Street about 2000 light years from the earth.
According to a new study published in The Astrophysical Journal the little 13.5 billion red dwarf hardly contains any heavy elements, suggesting that it was formed by an almost untouched cloud of material residues shortly after the Big Bang. In addition, because the little star is only a mass of the seventh sun and is made of primordial matter, it makes astronomers rethink the demographics of the very first stars.
The first stars formed in the universe probably hit about 200 million years after the Big Bang. These early stars were made from the material that was available to them at that time ̵
1; mostly hydrogen, a little helium and a touch of lithium.
When these stars became alive, they transformed their starting elements into increasingly heavier elements, which astronomers call “metals”. Eventually, some of these early stars blasted like supernovae, who threw their captured metals into the cosmos. Then the next set of stars was formed from the resulting, somewhat metal-enhanced clouds. This followed with each successive generation of stars enriching the next with more and more metals.
“Our Sun probably came from thousands of generations of short-lived massive stars who have lived and died since the Big Bang,” said senior author Kevin Schlaufman of Johns Hopkins University in a press release. “But what’s most interesting about this star is that maybe it just had an ancestor who separates it and the beginning of everything.”
It’s small. So, what?
Although a star that has existed shortly after the Big Bang is undoubtedly fascinating, the small magnitude of the old, low-key star (briefly referred to as 2MASS J18082002-5104378 B) is equally interesting.
Generally, astronomers believe that the universe’s first stars were extremely massive and lived quite short lives. In fact, until the late 1990s, many researchers thought that the early universe could only form massive stars .
But the view has been slowly developed over the years as simulations have become increasingly sophisticated. For example, a Japanese study in 2012 conducted simulations that showed the formation of low-mass stars in the early universe potentially triggered by nearby supernova explosions.
Although astronauts are not exactly sure how small 2MASS J18082002-5104378 B was formed, “this discovery tells us that the very first stars in the universe did not all need massive stars as long ago,” says astrophysic Andrew Casey from Monash University to ScienceAlert. “These old stars could be formed by very small amounts of material, meaning that some of these relics will come soon after Big Bang can still exist today. It gives us a new point of view of star formation in the early universe!”