Ross 248

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Stern
Ross 248
Nearby Stars (14ly Radius) ger.svg
AladinLite
Observation
dates equinox :  J2000.0 , epoch : J2000.0
Constellation Andromeda
Right ascension 23 h 41 m 55.04 s
declination + 44 ° 10 ′ 38.8 ″
Apparent brightness 12.28 (12.23 to 12.34) mag
Typing
B − V color index +1.91 
U − B color index +1.49 
R − I index +2.1 
Spectral class M5.5 Ve
Variable star type BY 
Astrometry
Radial velocity (−77.72 ± 0.12) km / s
parallax (316.96 ± 0.13)  mas
distance (10.28 ± 0.01)  ly
(3.15 ± 0.01)  pc
Visual absolute brightness M vis 14.79 likes
Proper movement 
Rec. Share: (112.69 ± 0.15)  mas / a
Dec. portion: (−1592.06 ± 0.11)  mas / a
Physical Properties
Dimensions 0.07  M ☉
radius 0.17  R ☉
Luminosity

0.0001  L ☉

Effective temperature 2000 to 3500  K
Other names
and catalog entries
Gliese catalog GJ 905 [1]
2MASS catalog 2MASS J23415498 + 4410407 [2]
Other names Ross 248 • HH Andromedae • LHS 549 • G 171-10 • GCTP 5736

Ross 248 (variable name HH Andromedae ) is a red, cool dwarf star in the constellation Andromeda . It belongs to the group of UV-Ceti stars and is therefore very rich in energy. With a distance of about 10.3 light years from the Sun , Ross 248 is ranked 10th among the closest known stars of our Sun and the closest star to the Sun in the constellation Andromeda. As the Voyager 2 spacecraft flies roughly in the direction of Ross 248, it will reach its nearest orbit point to this red dwarf at 1.7 light years in about 40,000 years .

According to a calculation by Robert AJ Matthews from 1993, Ross 248 will replace Proxima Centauri as the closest star to the Sun in 33,000 years due to its orbit and speed . However, due to its high speed, it will only bear this title for about 9,000 years.

discovery

Ross 248 was discovered in 1925 by Frank Elmore Ross (1874-1960), who also took the first good infrared and ultraviolet photographs of Venus in 1923. Ross reported for the first time in his "Second list of New Proper-Motion Stars" Astronomical Journal (36: 856).

Habitable zone

The habitable zone of Ross 248 is between about 0.022 to 0.054 AE and is thus closer than the orbit of Mercury at a distance to the sun of about 0.4 AE.

It was long suspected that Ross 248 had one or more companions, but several precision measurements of the Doppler shift in the late 1980s were negative. The Hubble Space Telescope also found no evidence to support this assumption.

See also

Web links

Individual evidence

  1. ↑ a b c d e f g Ross 248. In: SIMBAD . Center de Données astronomiques de Strasbourg , accessed November 6, 2018 .
  2. ↑ a b c HH And. In: VSX. AAVSO, accessed November 6, 2018 .
  3. ↑ Voyager 2 at voyager.jpl.nasa.gov
  4. ↑ The Close Approach of Stars in the Solar Neighborhood, bibcode : 1994QJRAS..35 .... 1M (English)