astroengine writes: A gargantuan star, measuring 1,300 times the size of our sun, has been uncovered 12,000 light-years from Earth — it is one of the ten biggest stars known to exist in our galaxy. The yellow hypergiant even dwarfs the famous stellar heavyweight Betelgeuse by 50 percent. While its hulking mass may be impressive, astronomers have also realized that HR 5171 is a double star with a smaller stellar sibling physically touching the surface of the larger star as they orbit one another. “The new observations also showed that this star has a very close binary partner, which was a real surprise,” said Olivier Chesneau, of the Observatoire de la Côte d’Azur in Nice, France. “The two stars are so close that they touch and the whole system resembles a gigantic peanut.