Upsilon Andromedae b
υ Andromedae b ( Upsilon Andromedae b ), short υ And b is an exoplanet that accompanies the yellow dwarf Upsilon Andromedae. Due to its high mass is assumed that it is a gas planet.
Together with two other planets ( Upsilon Andromedae c and Upsilon Andromedae d) make this one of the rare planetary systems so far with at least three known planets.
Discovery
As the majority of exoplanets discovered this was also using the radial velocity method. The planet was discovered by Paul Butler in 1996 and confirmed by other researchers.
Properties
The planet orbits its parent star every 4.617 days at a distance of about 0.06 astronomical units at an eccentricity of 0.02 percent and has a mass of about 0.69 MJ.