The radius of VY CMa is very roughly 1,420 times that of the Sun ( R ☉), which is close to the modelled maximum, the Hayashi limit, a volume nearly 8 billion times that of the Sun. VY CMa is embedded in the large molecular cloud Sh2-310, a large, quite local star-forming H II region-its diameter: 480 arcminutes (′) or 681 ly (209 pc). It produces strong molecular maser emission and was one of the first radio masers discovered. It is surrounded by a complex asymmetric circumstellar envelope (CSE) caused by its mass loss. It is about 17 ☘ times the mass of the Sun ( M ☉). Its great infrared (IR) excess makes it one of the brightest objects in the local part of the galaxy at wavelengths of 5 to 20 microns (µm) and indicates a dust shell or heated disk. No evidence has been found that it is part of a multiple star system. It is one of the largest known stars, one of the most luminous and massive red supergiants, and one of the most luminous stars in the Milky Way. VY Canis Majoris (abbreviated to VY CMa) is an extreme oxygen-rich (O-rich) red hypergiant (RHG) or red supergiant (RSG) and pulsating variable star 1.2 kiloparsecs (3,900 light-years) from the Solar System in the slightly southern constellation of Canis Major.
0 kommentar(er)
