VY Canis Majoris (VY CMa) is a red hypergiant star located in the constellation Canis Major. It is one of the largest stars. It is a high-luminosity M star with an effective temperature of about 3,490 K. During its main sequence, it would have been an O-type star with a mass of 15 to 35 solar mass. We originally estimated the diameter of VY CMa at 1,800 to 2,200 solar radii (3,063,904,800 km), which made it the largest of all stars for 5 years (between 2007-2012). The size of this star was revised in 2012 through improved measurement techniques. These improved measurements gave a radius of 1,420 ± 120 solar radii (1,977,653,280 ± 167,134,080 km). This means that it has shrunk in size. It has a luminosity of 270,000 solar luminosity and a mass of 17 ± 8 solar masses. We also discovered stars larger than VY Canis Majoris, they are called UY Scuti and Westerlund 1-26.
|Spectral type||M2.5 0|