COROT-3b

COROT-3b (formerly known as COROT-Exo-3b) is a brown dwarf or massive extrasolar planet with a mass 21.66 times that of Jupiter. The object orbits an F-type star in the constellation of Aquila. The orbit is circular and takes 4.2568 days to complete. It was discovered by the French-led COROT mission which detected the dimming of the parent star's light as COROT-3b passes in front of it (a situation called a transit).

Physical properties

The mass of COROT-3b was determined by the radial velocity method, which involves detecting the Doppler shift of the parent star's spectrum as it moves towards and away from Earth as a result of the orbiting companion. This method usually gives only a lower limit on the object's true mass: the measured quantity is the true mass multiplied by the sine of the inclination angle between the normal vector to the orbital plane of the companion and the line of sight between Earth and the star, an angle which in general is unknown. However, in the case of COROT-3b, the transits reveal the inclination angle and thus the true mass can be determined. In the case of COROT-3b, the mass is 21.66 times the mass of the planet Jupiter.