Ross 248

From Wikipedia, the free encyclopedia
Revision as of 16:17, 19 June 2025 by imported>Citation bot (Altered template type. Add: bibcode, doi, volume, journal, authors 1-1. Removed parameters. Some additions/deletions were parameter name changes. | Use this bot. Report bugs. | Suggested by Headbomb | #UCB_toolbar)
Jump to navigation Jump to search

Template:Short description Template:Sky

Ross 248
Script error: No such module "Location map".
Observation data
Epoch J2000      Equinox J2000
Constellation Andromeda
Right ascension Template:RA[1]
Declination Template:DEC[1]
Apparent magnitude (V) 12.23 - 12.34[2]
Characteristics
Spectral type M6 V[3]
U−B Template:Engvar +1.48Script error: No such module "Unsubst".
B−V Template:Engvar +1.92Script error: No such module "Unsubst".
Variable type BY Dra[2]
Astrometry
Radial velocity (Rv)Template:Val[1] km/s
Proper motion (μ) RA: Template:Val mas/yr[1]
Dec.: Template:Val mas/yr[1]
Parallax (π)316.4812±0.0444 mas[1]
DistanceTemplate:Rnd ± Template:Rnd ly
(Template:Rnd ± Template:Rnd pc)
Absolute magnitude (MV)14.79[4]
Details
Mass0.145[5] Template:Solar mass
Radius0.190[5] Template:Solar radius
Luminosity0.0022[6] Template:Solar luminosity
Surface gravity (log g)5.13[6] cgs
Temperature2,930[5] K
Metallicity [Fe/H]+0.23[5] dex
RotationTemplate:Val[7] days
Rotational velocity (v sin i)0.1[8] km/s
Age2.6[5] Gyr
Metallicity [Fe/H]{{{metal_fe2}}} dex
Other designations
HH Andromedae, HH And, 2MASS J23415498+4410407, G 171-010, GCTP 5736.00, GJ 905, LHS 549.[9]
Database references
SIMBADdata

Script error: No such module "Check for unknown parameters".

Ross 248, also called HH Andromedae or Gliese 905, is a small star approximately Template:Convert[10] from Earth in the northern constellation of Andromeda. Despite its proximity it is too dim to be seen with the naked eye.[11] It was first catalogued by Frank Elmore Ross in 1926 with his second list of proper-motion stars;[12] on which count it ranks 261st in the SIMBAD database. It was too dim to be included in the Hipparcos survey. In about 40,000 years, Voyager 2 will pass 1.7 light-years (9.7 trillion miles) from the star.

Within the next 80,000 years, Ross 248 is predicted to be the nearest star to the Sun for around 9,000 years, overtaking the current nearest star, the triple system Alpha Centauri.

Characteristics

File:HHAndLightCurve.png
A visual band light curve for HH Andromedae, adapted from Weis (1994)[13]

This star has about 14% of the Sun's mass and 19% of the Sun's radius, but only 0.2% of the Sun's luminosity. It has a stellar classification of M6 V,[3] which indicates it is a type of main-sequence star known as a red dwarf. This is a chromospherically-active star.[14] With high probability, there appears to be a long-term cycle of variability with a period of 4.2 years. This variability causes the star to range in visual magnitude from 12.23 to 12.34.[13] In 1950, this became the first star to have a small variation in magnitude attributed to spots on its photosphere as it rotates,[15] a class known as BY Draconis variables.[2]

Examining the proper motion of Ross 248 has found no evidence of a brown dwarf or stellar companion orbiting between 100–1,400 AU,[16] and other unsuccessful searches have been attempted using both the Hubble Space Telescope Wide Field Planetary Camera[4] and by near-infrared speckle interferometry.[17] Long-term observations by the Sproul Observatory show no astrometric perturbations by any unseen companion.[15]

Distance from the Sun

File:Near-stars-past-future-en.svg
Distances of the nearest stars from 20,000 years ago until 80,000 years in the future

The space velocity components of this star in the galactic coordinate system are [U, V, W] = [[[:Template:Val]], Template:Val, Template:Val] km/s.[10] The trajectory of Ross 248 will bring it closer to the Solar System. In 1993, Matthews projected that in about 33,000 years it would enter a period of about 9,000 years as the closest star to the Sun, as close as Template:Convert in 36,000 years.[18] A more precise estimate in 2022 has it approaching to within Template:Cvt in 36,500 years.[19]

Any future spacecraft that escaped the Solar System with a velocity of 25.4 km/s would reach this star 37,000 years from now, when the star just passes its nearest approach. By comparison, the Voyager 1 has an escape velocity of 16.6 km/s.[20]

Voyager 2 is not headed toward any particular star, although in roughly 42,000 years, it will pass the star Ross 248 at a distance of 1.7 light-years.[21]

The closest stellar neighbors to Ross 248 are the binary systems Groombridge 34, at 1.8 light-years away, and Kruger 60, at 4.5 light-years.[22]

See also

References

Template:Reflist

Sources

External links

Template:Nearest systems Template:Stars of Andromeda Template:Portal bar

  1. ↑ a b c d e Cite error: Invalid <ref> tag; no text was provided for refs named GaiaDR3
  2. ↑ a b c Cite error: Invalid <ref> tag; no text was provided for refs named gcvs
  3. ↑ a b Cite error: Invalid <ref> tag; no text was provided for refs named apj704_2_975
  4. ↑ a b Cite error: Invalid <ref> tag; no text was provided for refs named apj119
  5. ↑ a b c d e Cite error: Invalid <ref> tag; no text was provided for refs named mann2015
  6. ↑ a b Cite error: Invalid <ref> tag; no text was provided for refs named carmenes
  7. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named Kemmer2025
  8. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named newton2015
  9. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named SIMBAD
  10. ↑ a b Cite error: Invalid <ref> tag; no text was provided for refs named apjss82
  11. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named routray2004
  12. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named aj36_856_124
  13. ↑ a b Cite error: Invalid <ref> tag; no text was provided for refs named aj107_3_1135
  14. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named poveda_allen_christine1996
  15. ↑ a b Cite error: Invalid <ref> tag; no text was provided for refs named ssr22
  16. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named aj123_4_2027
  17. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named aaa325_159
  18. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named Matthews1993
  19. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named Bailer-Jones_2022
  20. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named baa217_552
  21. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named Bailer-Jones2019
  22. ↑ Cite error: Invalid <ref> tag; no text was provided for refs named solstation
Retrieved from "http://debianws.lexgopc.com/wiki143/index.php?title=Ross_248&oldid=676879"