Kapteyn's Star

Kapteyn's Star is a class M1 red subdwarf about 12.83 light-years (3.93 parsecs) from Earth in the southern constellation Pictor; it is the closest halo star to the Solar System and one of the nearest stars. With a slightly variable apparent magnitude of about 8.8, it is visible through binoculars or a telescope.

Its diameter is 30% of the Sun's, but its luminosity just 1.2% that of the Sun. It may have once been part of the globular cluster Omega Centauri, itself the likely core of a dwarf galaxy swallowed up by the Milky Way in the distant past. The discovery of two planets—Kapteyn b and Kapteyn c—was announced in 2014, but had a mixed history of rejections and confirmations, until a 2021 study refuted both planets. The "planets" are in fact likely artifacts of the star's rotation and activity.