ESO’s Very Large Telescope (VLT)observed a star sparkling in the forbidden zone, amazing the Astronomers on September 1, 2011. Astronomers named it as SDSS J102915+172927. Its estimated to be about 13 billion years old.
Stars are dropped into 3 groups out of which one is Population 1. These stars contain metals which account for about 2 to 3 % of the star's composition. The second population 2 stars have 0.01 to 0.1 % of metals whereas the third type dubbed population 3 stars don't contain metals at all. One more thing about these stars is that due to their heavy mass, its predicted that they would have died at the beginning of the universe, itself. Population 3 stars can only be cooled by the hydrogen. Its also proved in recent studies that the death of these stars would have enriched the surrounding galactic medium with heavy amounts of carbon and oxygen.
But this star, now discovered is found to be devoid of any heavier metals.So according to the above discussed facts, this star should be one of the population 3 stars. But the odd thing about this star is that it doesn't even contain any traces of the carbon and oxygen and this amazes the astronomers to a confusing extent. Because this means it didn't have anything reasonable to cool the star, as far as we know.
Caffau, lead author of the paper tells Astronomy Now Magazine tried to explain it this way: “One mechanism is cooling by dust, that leads to a much lower critical metallicity than cooling by fine structure lines of CII and OI,” and “Another mechanism is fragmentation. If a massive cloud collapsing to form a high mass stars breaks up a few small mass fragments, these can form low mass stars.” One more thing which made this star stand in the forbidden zone is that this star even lacks the lithium, which is supposed to be contained in along with the many other stars in that galaxy. So the methodology involved in the formation of this star is still a mystery and as with every strange thing happening in the universe, I hope this is gonna reveal some mysteries about the origin of the universe, as an astro-lover.
Ref: Astronomy Now magazine.
Sept 2nd, 2011.
Pranu :)
Figure is a pie-diagram of the constituents of the star SDSS J102915+172927 and lack of the heavier elements as well as it's percentage of the total composition
But this star, now discovered is found to be devoid of any heavier metals.So according to the above discussed facts, this star should be one of the population 3 stars. But the odd thing about this star is that it doesn't even contain any traces of the carbon and oxygen and this amazes the astronomers to a confusing extent. Because this means it didn't have anything reasonable to cool the star, as far as we know.
Caffau, lead author of the paper tells Astronomy Now Magazine tried to explain it this way: “One mechanism is cooling by dust, that leads to a much lower critical metallicity than cooling by fine structure lines of CII and OI,” and “Another mechanism is fragmentation. If a massive cloud collapsing to form a high mass stars breaks up a few small mass fragments, these can form low mass stars.” One more thing which made this star stand in the forbidden zone is that this star even lacks the lithium, which is supposed to be contained in along with the many other stars in that galaxy. So the methodology involved in the formation of this star is still a mystery and as with every strange thing happening in the universe, I hope this is gonna reveal some mysteries about the origin of the universe, as an astro-lover.
Ref: Astronomy Now magazine.
Sept 2nd, 2011.
Pranu :)
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