Alien planets. Computer artwork of the outermost planet of the red dwarf star Gliese 876. The inner planet (Gliese 876c) is at upper right, partially eclipsing Gliese 876. The planets are Jupiter-like gas giants, and the outer planet (Gliese 876b) is shown with rings. Starspots are seen on the star, along with flare activity. A moon of Gl876b is at lower centre. Gl876b orbits in 61 days; Gl876c in 30 days. Gl876b was discovered in 1998 but its orbit hid that of Gl876c, which was not found until 2001. Gl876b has a mass 600 times that of Earth and orbits some 31.5 million kilometres (km) from the star. Gl876c has a mass 180 times that of Earth and an orbital radius of 19.5 million km.