Gliese 49 is a star in the northern constellation of Cassiopeia. Visually, it is located 106 arcminutes north of the bright star γ Cassiopeiae. With an apparent visual magnitude of 9.56,[2] it is not observable with the naked eye. It is located, based on the reduction of parallax data of Gaia (101.47±0.03 mas), 32.1 light-years away from the Solar System. The star is drifting closer to the Sun with a radial velocity of −6 km/s.[1]

Gliese 49
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Cassiopeia
Right ascension 01h 02m 38.86799s[1]
Declination +62° 20′ 42.1728″[1]
Apparent magnitude (V) 9.56±0.02[2]
Characteristics
Spectral type M1.5 V[2]
B−V color index 1.463±0.032[3]
Astrometry
Radial velocity (Rv)−5.974±0.0011[1] km/s
Proper motion (μ) RA: +731.135[1] mas/yr
Dec.: +90.690[1] mas/yr
Parallax (π)101.4238 ± 0.0169 mas[4]
Distance32.158 ± 0.005 ly
(9.860 ± 0.002 pc)
Absolute magnitude (MV)9.55[3]
Details[2]
Mass0.515±0.019 M
Radius0.511±0.018 R
Luminosity (bolometric)0.04938±0.00090 L
Surface gravity (log g)4.69±0.07 cgs
Temperature3,805±51 K
Metallicity [Fe/H]+0.13±0.16 dex
Rotation18.86+0.10
−0.09
 d
Rotational velocity (v sin i)<2 km/s
Other designations
BD+61°195, GJ 49, HIP 4872, LTT 10363[5]
Database references
SIMBADdata

This object is a red dwarf star of spectral type M1.5V.[2] Much dimmer than the Sun, it has a total luminosity that is 4.9% that of the Sun;[2][6] it is, however, much brighter than other nearby red dwarfs such as Proxima Centauri or Wolf 359. It has an effective temperature of 3,805±51 K. Its mass is 52% that of the Sun, and 51% of its radius.[2]

It rotates on its axis with a projected rotation speed of under 2 km/s, and has a rotation period of 18.86 days. It has a metallic content similar to that of the Sun, with its index of metallicity [M / H] = +0.03.[7] Although its age is not known exactly, it is younger than 250 million years.[citation needed]

Gliese 49 has a similar proper motion to the red dwarf flare star V388 Cassiopeiae. The visual separation between the two is 295 arcseconds, which implies that the real distance between them is over 2,900 AU. Both stars are associated with the Hyades, as suggested by its young age and chromospheric activity levels.[8]

Planetary system

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One known planet is known to orbit Gliese 49. Gliese 49 b is a super-Earth planet detected by the radial velocity method.[2]

The Gliese 49 planetary system
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(days)
Eccentricity Inclination Radius
b 5.63+0.67
−0.68
 M🜨
0.0905 ± 0.0011 13.8508+0.0053
−0.0051
0.363+0.099
−0.096

References

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  1. ^ a b c d e f 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.
  2. ^ a b c d e f g h Perger, M.; et al. (April 2019). "Gliese 49: Activity evolution and detection of a super-Earth". Astronomy & Astrophysics. 624: 19. arXiv:1903.04808. Bibcode:2019A&A...624A.123P. doi:10.1051/0004-6361/201935192. ISSN 0004-6361. S2CID 85497416. A123.
  3. ^ a b Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters, 38 (5): 331, arXiv:1108.4971, Bibcode:2012AstL...38..331A, doi:10.1134/S1063773712050015, S2CID 119257644.
  4. ^ 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. (Erratum: doi:10.1051/0004-6361/202039657e). Gaia EDR3 record for this source at VizieR.
  5. ^ "GJ 49". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-12-16.
  6. ^ Morales, J. C.; et al. (2008). "The effect of activity on stellar temperatures and radii". Astronomy and Astrophysics. 478 (2): 507–512. arXiv:0711.3523. Bibcode:2008A&A...478..507M. doi:10.1051/0004-6361:20078324. S2CID 16238033.
  7. ^ Houdebine, E. R. (2010). "Observation and modelling of main-sequence star chromospheres – XIV. Rotation of dM1 stars". Monthly Notices of the Royal Astronomical Society. 407 (3): 1657–1673. Bibcode:2010MNRAS.407.1657H. doi:10.1111/j.1365-2966.2010.16827.x.
  8. ^ Makarov, V. V.; et al. (2008). "Common Proper Motion Companions to Nearby Stars: Ages and Evolution". The Astrophysical Journal. 687 (1): 566–578. arXiv:0808.3414. Bibcode:2008ApJ...687..566M. doi:10.1086/591638. S2CID 17811620.