Omega Carinae
Omega Carinae is a star in the constellation Carina. Its name is a Bayer designation that is Latinized from ω Carinae, and abbreviated Omega Car or ω Car. With a declination greater than 70 degrees south of the celestial equator, it is the most southerly of the bright stars of Carina, and it is part of a southern asterism known as the Diamond Cross. This naked eye star has an apparent [visual magnitude] of 3.3 and is located at a distance of about from Earth.
Properties
Omega Carinae has a stellar classification of B8 IIIe, which places it in the category of Be stars, that display emission lines of hydrogen their spectrum. Omega Carinae is a shell star, having a circumstellar disk of gas surrounding its equator. The luminosity class of III indicates it has evolved into a giant star, having exhausted the hydrogen at its core and left the main sequence. The effective temperature of in its outer envelope is what gives this star the blue-white hue that is characteristic of B-type stars.This star is rotating rapidly with a projected rotational velocity of, which gives a lower limit to the star's azimuthal velocity along the equator. The critical equatorial velocity, at which the star would begin to break up, is. The star's axis of rotation is inclined by an estimated angle of 70.8° to the line of sight from the Earth.
In the next 7500 years, the south Celestial pole will pass close to this star and then I Carinae.