New stars being born at our galaxy's edge
Welcome the arrival of newborn stars in our galaxy. According to a thrilling research, gas from another galaxy is hitting our own, triggering the birth of bright new stars and adding fresh lustre to the Milky Way.
For the first time, astronomers have detected stars in an enormous stream of gas shed by the Magellanic Clouds, the two brightest galaxies that orbit our own.
"This is the one and only galaxy interaction we can model in very much detail as other collisions of gas clouds between galaxies are farther away and thus harder to observe," said Dana Casetti-Dinescu, an astronomer at Southern Connecticut State University in the US.
The Magellanic Clouds are known to have active star formation and stargazers can see the pair with the naked eye.
But now, astronomers have found signs of star formation in a giant tail of gas that is trailing these satellite galaxies of the Milky Way.
The newborn stars offer insight into processes that occurred in the ancient universe, when small, gas-rich galaxies smashed together to give rise to giants like the Milky Way, said a report in the journal Nature.
The Large Magellanic Cloud is just 160,000 light-years from earth, whereas the Small Magellanic Cloud is 200,000 light-years distant and 75,000 light-years away from its partner.
As the two galaxies orbit the Milky Way, they probably orbit each another, too.
The long stream of gas that trails behind the two galaxies is named the Magellanic Stream. It consists mostly of neutral hydrogen atoms.
A shorter gaseous component leads the Magellanic Clouds and is, therefore, called the Leading Arm.
"This is the first credible evidence of stars associated with the Leading Arm," David Nidever from University of Michigan was quoted as saying.
From the tip of the Leading Arm to the far end of the Magellanic Stream, this gaseous strand is at least 200 degrees long and stretches across more than half a million light-years of space.
Although the stars owe their births to gas from the Magellanic Clouds, they now revolve around a new master, the Milky Way Galaxy, the findings, published in the Astrophysical Journal Letters.
(Posted on 06-04-2014)