Teegarden's star
Teegarden's Star, also known as SO025300.5+165258, is a star in the constellation Aries which was found in 2003 to have a very large proper motion (5.06±0.03 arcsec/year). Only seven stars with such large proper motions are currently known.It appears to be a red dwarf, a class of low temperature and low luminosity stars. This would explain why it was not discovered earlier, since it has an apparent magnitude of only 15.4 (and an absolute magnitude of 18.5).
The parallax was measured as 0.43±0.13 arcsec. The relatively high uncertainty should be reduced soon as newer measurements are made. If the parallax measurement is accurate, Teegarden's Star is the third star in order of distance from the Sun, ranking between Barnard's Star and Wolf 359, and its distance is only 7.50 light years. However, the anomalously low luminosity and high uncertainty in the parallax suggest that it may be somewhat farther away, still one of the Sun's nearest neighbors but not nearly as high in the ranking in order of distance.
It was discovered on images taken by the NEAT program operated by NASA.
See also: