Ross 248
Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Andromeda |
Right ascension | 23h 41m 55.0361s[1] |
Declination | +44° 10′ 38.825″[1] |
Apparent magnitude (V) | 12.23 - 12.34[2] |
Characteristics | |
Spectral type | M6 V[3] |
U−B color index | +1.48[citation needed] |
B−V color index | +1.92[citation needed] |
Variable type | BY Dra[2] |
Astrometry | |
Radial velocity (Rv) | –75.2 ± 3.7[4] km/s |
Proper motion (μ) | RA: 112.692±0.153[1] mas/yr Dec.: −1592.055±0.112[1] mas/yr |
Parallax (π) | 316.4812 ± 0.0444[5] mas |
Distance | 10.306 ± 0.001 ly (3.1597 ± 0.0004 pc) |
Absolute magnitude (MV) | 14.79[6] |
Details | |
Mass | 0.136[3] M☉ |
Radius | 0.16[7] R☉ |
Luminosity | 0.0018[8] L☉ |
Surface gravity (log g) | 5.12[9] cgs |
Temperature | 2,799[9] K |
Rotational velocity (v sin i) | 1.2[3] km/s |
Other designations | |
Database references | |
SIMBAD | data |
Ross 248, also called HH Andromedae or Gliese 905, is a small star approximately 10.30 light-years (3.16 parsecs)[11] from Earth in the northern constellation of Andromeda. 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 nearest star to the Sun for a brief time, overtaking the current nearest star and triple system, Alpha Centauri. Despite its proximity it is too dim to be seen with the naked eye.[13]
Characteristics[]
This star has about 12% of the Sun's mass and 16% 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.[15] In 1950, this became the first star to have a small variation in magnitude attributed to spots on its photosphere as it rotates,[16] 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 100–1400 AU,[17] and other unsuccessful searches have been attempted using both the Hubble Space Telescope Wide Field Planetary Camera[6] and by near-infrared speckle interferometry.[18] Long-term observations by the Sproul Observatory show no astrometric perturbations by any unseen companion.[16]
Distance from the Sun[]
The space velocity components of this star in the galactic coordinate system are [U, V, W] = [–32.9 ± 0.7, –74.3 ± 1.3, 0.0 ± 1.4] km/s.[11] 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 3.024 light-years (0.927 parsecs) in 36,000 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]
Field star[]
Ross 248 is located nearly along the line of sight to star PLX 5735 but is not physically associated.
Name | PLX 5735 |
---|---|
Right ascension | 23h 41m 54s |
Declination | +44° 14′ 00″ |
Apparent magnitude (V) | 12.6 |
Spectral type | A5 |
Absolute stellar parallax | 0.7846 |
Distance in light years | 4,200 |
Database references | Simbad |
See also[]
- List of nearest stars and brown dwarfs
- Lists of stars
- Ross 248 in fiction
References[]
- ^ Jump up to: a b c d Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
- ^ Jump up to: a b c Samus, N. N.; Durlevich, O. V.; et al. (2009). "VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013)". VizieR On-line Data Catalog: B/GCVS. Originally Published in: 2009yCat....102025S. 1: B/gcvs. Bibcode:2009yCat....102025S.
- ^ Jump up to: a b c d Jenkins, J. S.; Ramsey, L. W.; Jones, H. R. A.; Pavlenko, Y.; Gallardo, J.; Barnes, J. R.; Pinfield, D. J. (October 2009). "Rotational Velocities for M Dwarfs". The Astrophysical Journal. 704 (2): 975–988. arXiv:0908.4092. Bibcode:2009ApJ...704..975J. doi:10.1088/0004-637X/704/2/975. S2CID 119203469.
- ^ Deshpande, R.; Martín, Eduardo L.; Montgomery, M. M.; Zapatero-Osorio, María Rosa; Rodler, F.; del Burgo, C.; Bao, N. Phan; Lyubchik, Y.; Tata, R.; Bouy, H.; Pavlenko, Y. (2012). "Intermediate Resolution Near-infrared Spectroscopy of 36 Late M Dwarfs". The Astronomical Journal. 144 (4): 99. arXiv:1207.2781. Bibcode:2012AJ....144...99D. doi:10.1088/0004-6256/144/4/99. ISSN 1538-3881. S2CID 119301281.
- ^ Brown, A. G. A.; et al. (Gaia collaboration) (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics. 649: A1. arXiv:2012.01533. Bibcode:2021A&A...649A...1G. doi:10.1051/0004-6361/202039657. S2CID 227254300. Gaia EDR3 record for this source at VizieR.
- ^ Jump up to: a b Schroeder, Daniel J.; et al. (2000). "A Search for Faint Companions to Nearby Stars Using the Wide Field Planetary Camera 2". The Astronomical Journal. 119 (2): 906–922. Bibcode:2000AJ....119..906S. doi:10.1086/301227.
- ^ Johnson, H. M.; Wright, C. D. (November 1983). "Predicted infrared brightness of stars within 25 parsecs of the Sun". Astrophysical Journal Supplement Series. 53: 643–711, 705. Bibcode:1983ApJS...53..643J. doi:10.1086/190905.
- ^ West, Frederick R. (June 1999). "Monitoring Nearby Stars for Transits by Extrasolar Jovial Planets, II: Transits of M-Type (Red) Dwarf Stars by Close Extrasolar Giant (Jovian) Planets". The Journal of the American Association of Variable Star Observers. 27 (1): 77–78. Bibcode:1999JAVSO..27...77W.
- ^ Jump up to: a b Cenarro, A. J.; et al. (2007). "Medium-resolution Isaac Newton Telescope Library of Empirical Spectra – II. The Stellar Atmospheric Parameters". Monthly Notices of the Royal Astronomical Society. 374 (2): 664–690. arXiv:astro-ph/0611618. Bibcode:2007MNRAS.374..664C. doi:10.1111/j.1365-2966.2006.11196.x. S2CID 119428437.
- ^ "V* HH And". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2009-09-06.
- ^ Jump up to: a b Leggett, S. K. (September 1992). "Infrared colors of low-mass stars". Astrophysical Journal Supplement Series. 82 (1): 351–394. Bibcode:1992ApJS...82..351L. doi:10.1086/191720.
- ^ Ross, Frank E. (February 1926). "New proper-motion stars, (second list)". Astronomical Journal. 36 (856): 124–128. Bibcode:1926AJ.....36..124R. doi:10.1086/104699.
- ^ Routray, Sudhir K. (2004). Light Years Away: The Whole Creation at a Glance. iUniverse. p. 31. ISBN 0-595-33582-9.
- ^ Poveda, Arcadio; Allen, Christine; Herrera, Miguel Angel (1996). "Chromospheric Activity, Stellar Winds and Red Stragglers". Workshop on Colliding Winds in Binary Stars to Honor Jorge Sahade. 5. Universidad Nacional Autonoma de Mexico. pp. 16–20. Bibcode:1996RMxAC...5...16P.
- ^ Weis, Edward W. (March 1994). "Long term variability in dwarf M stars". Astronomical Journal. 107 (3): 1135–1140. Bibcode:1994AJ....107.1135W. doi:10.1086/116925.
- ^ Jump up to: a b Lippincott, S. L. (July 1978). "Astrometric search for unseen stellar and sub-stellar companions to nearby stars and the possibility of their detection". Space Science Reviews. 22 (2): 153–189. Bibcode:1978SSRv...22..153L. doi:10.1007/BF00212072. S2CID 123491684.
- ^ Hinz, Joannah L.; et al. (February 2002). "A Near-Infrared, Wide-Field, Proper-Motion Search for Brown Dwarfs". The Astronomical Journal. 123 (4): 2027–2032. arXiv:astro-ph/0201140. Bibcode:2002AJ....123.2027H. doi:10.1086/339555. S2CID 12737223.
- ^ Leinert, C.; Henry, T.; Glindemann, A.; McCarthy, D. W. Jr. (September 1997). "A search for companions to nearby southern M dwarfs with near-infrared speckle interferometry". Astronomy and Astrophysics. 325: 159–166. Bibcode:1997A&A...325..159L.
- ^ Matthews, R. A. J. (Spring 1994). "The Close Approach of Stars in the Solar Neighborhood". Quarterly Journal of the Royal Astronomical Society. 35 (1): 1. Bibcode:1994QJRAS..35....1M.
- ^ West, F. R. (March 1985). "A Suggested Future Space Mission to the Low-Luminosity Star Ross 248=Gliese 905". Bulletin of the American Astronomical Society. 17: 552. Bibcode:1985BAAS...17..552W.
Sources[]
- Riaz, Basmah; Gizis, John E.; Harvin, James (2006). "Identification of New M Dwarfs in the Solar Neighborhood". The Astronomical Journal. 132 (2): 866–872. arXiv:astro-ph/0606617. Bibcode:2006AJ....132..866R. doi:10.1086/505632. Table 1.
- Dittmann, Jason A.; Irwin, Jonathan M.; Charbonneau, David; Berta-Thompson, Zachory K. (2014). "Trigonometric Parallaxes for 1507 Nearby Mid-to-late M Dwarfs". The Astrophysical Journal. 784 (2): 156. arXiv:1312.3241. Bibcode:2014ApJ...784..156D. doi:10.1088/0004-637X/784/2/156. S2CID 18789867. Table with parallaxes.
External links[]
- Andromeda (constellation)
- Local Bubble
- M-type main-sequence stars
- Flare stars
- Ross objects
- Gliese and GJ objects
- Objects with variable star designations
- BY Draconis variables