VY Canis Majoris (VY CMa) is a red hypergiant star located in the constellation Canis Major. At between 1800 to 2100 solar radii (approx 2,505,600,000 to 2,923,200,000 km across or 1,556,534,837 to 1,816,267,995 miles), it is the largest known star and also one of the most luminous known.
It is located about 1.5 kiloparsecs (4.6×1016 km) or about 4,900 light years away from Earth. Unlike most hypergiant stars, which occur in either binary or multiple star systems, VY CMa is a single star. It is categorized as a semiregular variable and has an estimated period of 2000 days.
It would take over 7,000,000,000,000,000 (7×1015 or 7 quadrillion) Earths to fill the volume of VY Canis Majoris.
If the Earth were to be represented by a sphere 1 cm in diameter, the Sun would be represented as a sphere with a diameter of109 cm, at a distance of 117 meters. At these scales, VY Canis Majoris would have a diameter of approximately 2.3 km, assuming the upper limit estimate of its radius.