Milky Way’s Farthest Stars May Have Come From Another Galaxy

Posted: Jan 16 2017, 2:26pm CST | by , Updated: Jan 16 2017, 2:39pm CST, in News | Latest Science News

 

Milky Way’s Farthest Stars may have Come from Another Galaxy
Credit: NASA
 

Computer simulations suggests that Milky Way is a cosmic theif

Some of the farthest stars of Milky Way may be stolen from another galaxy.

According to a new research, five distant stars are lying in such an unusual place, well outside the Milky Way’s spiral disc, that it appears they may have been dragged from somewhere else. Computer simulations suggest that these stars are likely come from Sagittarius dwarf – a satellite galaxy of Milky Way.

Milky Way is surrounded by some 50 mini galaxies and Sagittarius dwarf is one of them. It is located some 70,000 light years away from Earth, making it an ideal target for theft.

Using computer modeling, researchers tracked the movements of dwarf galaxy over the past 8 billion years and recreated the scenario of an interaction between the two. Researchers claim that Milky Way had snatched those stars when Sagittarius dwarf strayed too close to it and pulled it even closer using gravitational tides.  

“The starting speed and approach angle have a big effect on the orbit, just like the speed and angle of a missile launch affects its trajectory.” Harvard-Smithsonian Center for Astrophysics (CfA) theorist Avi Loeb said.

These distant stars are placed some 300,000 light years away from Earth. Moreover, they are also a part of star streams that are extending as far as one million light-years across space, displaying one of the largest structures observable in the sky.

“The star streams that have been mapped so far are like creeks compared to the giant river of stars we predict will be observed eventually.” Lead author Marion Dierickx said.

Researchers suggest that Sagittarius dwarf was a massive galaxy in the earlier stages of its life. It weighted about 10 billions of Sun or about one percent of the total mass of the Milky Way. The galaxy lost around one third of its stars alongside lots of dark matter over time, leaving it with a relatively reduced weight.

 

 

This story may contain affiliate links.

Comments

The Author


Hira Bashir covers daily affairs around the world.

 

 

Advertisement

comments powered by Disqus