William Atkins
Saturday, 24 July 2010 00:59
Science -
Space
Page 1 of 4
U.S. astronomers using the Hubble Space Telescope have conjectured that a very rare hypervelocity star (a really fast one) was flung out of our Milky Way galaxy by its supermassive black hole over one hundred million years ago.
The hypervelocity star, called
HE 0437-5439, is one of the fastest stars ever detected by humans.
It travels at a speed of approximately 1.6 million miles (2.6 million kilometers) per hour—or about 723 kilometers per second—which is about three times the speed at which our own Sun travels around the galaxy.
HE 0437-5439, discovered in 2005, is considered by astronomers to be a massive, unbound hypervelocity main sequence B-type star--and a super-hot, massive, rejuvenated (formed from two lighter stars) blue star, or what is called a blue straggler.
It is a young star, being only about 30 million years old. The star’s mass is almost nine times greater than our Sun’s mass.
The star is located 200,000 light years away in the direction of the Dorado constellation, just northwest of the Large Magellanic Cloud (LMC) and further away in distance than the LMC.
According to the NASA media brief “
NASA'S Hubble Shows Hyperfast Star Was Booted From Milky Way,” here is what astronomers think happened about one hundred million years ago, based on data provided by the Hubble Space Telescope:
“The star may have been created in a cosmic misstep. A hundred million years ago, a triple-star system was traveling through the bustling center of our Milky Way galaxy when it wandered too close to the galaxy's giant black hole. The black hole captured one of the stars and hurled the other two out of the Milky Way. The two outbound stars merged to form a super-hot blue star traveling at incredible speeds.”NASA states that the star is
“one of the fastest ever detected.”Page two continues with more on hypervelocity stars and how valuable Hubble is in detecting them.
