It is among the largest object ever spotted in the Universe - and has a diameter more than 1300 times that of our Sun.

Dubbed a 'hypergiant', the yellow star was part of a unique double double star system, with the second component so close that it is in contact with the main star - making it look rather like a table tennis bat.

Astronomers say the find is unique - and could help explain how stars interact.
It was spotted by ESO’s Very Large Telescope Interferometer, and is the largest yellow star — and one of the ten largest stars found so far.

Observations spanning over sixty years, some from amateur observers, also indicate that this rare and remarkable object is changing very rapidly and has been caught during a very brief phase of its life.
'The new observations also showed that this star has a very close binary partner, which was a real surprise,' says Olivier Chesneau, who led the research.

'The two stars are so close that they touch and the whole system resembles a gigantic peanut.'

The astronomers made use of a technique called interferometry to combine the light collected from multiple individual telescopes, effectively creating a giant telescope up to 140 metres in size.

Yellow hypergiants are very rare, with only a dozen or so known in our galaxy — the best-known example being Rho Cassiopeiae.

They are among the biggest and brightest stars known and are at a stage of their lives when they are unstable and changing rapidly.

Due to this instability, yellow hypergiants also expel material outwards, forming a large, extended atmosphere around the star.

Read more: http://www.dailymail.co.uk/sciencetech/article-2579525/The-yellow-hypergiant-star-Massive-object-1300-times-size-Sun-spotted.html#ixzz2vr5n4LUB