Teegarden's star

Starbox begin
name=Teegarden's star Starbox observe
epoch=J2000
constell=Aries
ra=02h 53m 00.9s
dec=+16° 52' 53"
appmag_v=15.4 Starbox character
class=M6.5V
r-i =
v-r =
b-v=
u-b=
variable= Starbox astrometry
radial_v=
prop_mo_ra=+239.27
prop_mo_dec=-3810.1
parallax=259
p_error=4
absmag_v=17.5 Starbox detail
mass=0.13
radius=0.075
luminosity=0.000009
temperature=2,000–3,500
metal=
rotation=
age= Starbox catalog
names=SO025300.5+165258Starbox reference
Simbad=Teegarden+s+Star
ARICNS =

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 17.47).

The parallax was initially measured as 0.43±0.13 arcsec. This would have placed its distance at only 7.50 light years, making Teegarden's Star only the third star in order of distance from the Sun, ranking between Barnard's Star and Wolf 359. However, even at that time the anomalously low luminosity (the absolute magnitude would have been 18.5) and high uncertainty in the parallax suggested that it was in fact somewhat farther away, still one of the Sun's nearest neighbors but not nearly as high in the ranking in order of distance. More recent distance measurements of 12.5–12.6 light years appear to have confirmed this.

Teegarden's Star was discovered on images taken by the NEAT program operated by NASA. Its name comes from its principal discoverer, Dr. Bonnard Teegarden, an astrophysicist at NASA's Goddard Space Flight Center.

It is thought to be quite likely that many other dim and easily overlooked red dwarf stars exist in the nearest 20 light years, as stellar population surveys show their count to be quite lower than otherwise expected.

ee also

* List of nearest stars

External links

* [http://xxx.lanl.gov/abs/astro-ph/0302206 Original article abstract]
* [http://www.chara.gsu.edu/RECONS/new.SO025300.5+165258.htm Research Consortium on Nearby Stars (RECONS) article]
* [http://www.solstation.com/stars/so025300.htm SolStation.com]
* http://jumk.de/astronomie/near-stars/teegardens-star.shtml
* http://www.richweb.f9.co.uk/astro/nearby_stars.htm
* [http://aladin.u-strasbg.fr/AladinPreview?-c=02+53+00.89%2B16+52+52.7&ident=NAME+Teegarden%27s+star&submit=Aladin+previewer Image Teegarden's star]