Scientists at the European Southern Observatory (ESO) have found a large yellow star with the use of the Very Large Telescope Interferometer (VLTI).
The scientists said the yellow hypergiant in the constellation Centaurus is the biggest yellow star to be discovered, and that it could possibly be one of the top 10 biggest stars discovered to date, according to AOL.
The star, named HR 5171, is 1,300 times the diameter of the Sun, and observations from the past 60 years show that the hypergiant is changing quickly and that it was found during a short phase of its life, Astronomy Magazine reported. With the help of the VLTI, Olivier Chesneau from the Observatory de la Cote d'Azur in Nice, France, and a team of researchers found that the star is 50 percent bigger than the red supergiant Betelguese and almost 1 million times brighter than the Sun.
"The new observations also showed that this star has a very close binary partner, which was a real surprise," Chesneau said. "The two stars are so close that they touch, and the whole system resembles a gigantic peanut."
While HR 5171 is 12,000 light-years away, it is bright enough that it can be spotted by the naked eye under proper conditions, according to Discover Magazine.
The scientists used a technique called interferometry, which involves combining light collected from different telescopes and creating one huge telescope about 140 meters in size. Yellow supergiants are one of the rarest types of stars, and only a dozen are known in our galaxy, according to Astronomy Magazine. They are also one of the brightest and largest stars known to man, and are at a stage in their lives where they change quickly and are unstable. The instability causes the stars to release material, which forms a large atmosphere around the star.
The astronomers also found that HR 5171 is in an eclipsing binary system with a smaller star, which orbits the larger star every 1,300 days.
"The companion we have found is very significant as it can have an influence on the fate of HR 5171 A, for example, stripping off its outer layers and modifying its evolution," Chesneau said.
