Astronomy:Gliese 754
Coordinates: 
19h 20m 47.98349s, −45° 33′ 29.6292″
  Gliese 754 Location of Gliese 754 in the constellation Telescopium | |
| Observation data Equinox J2000.0]] (ICRS) | |
|---|---|
| Constellation | Telescopium |
| Right ascension | 19h 20m 47.98432s[1] |
| Declination | −45° 33′ 29.6435″[1] |
| Apparent magnitude (V) | 12.25[2] |
| Characteristics | |
| Spectral type | M4V[2] |
| Astrometry | |
| Radial velocity (Rv) | +6.04±0.19[1] km/s |
| Proper motion (μ) | RA: +658.775[1] mas/yr Dec.: −2,896.150[1] mas/yr |
| Parallax (π) | 169.2351 ± 0.0588[1] mas |
| Distance | 19.272 ± 0.007 ly (5.909 ± 0.002 pc) |
| Details[3] | |
| Mass | 0.173 M☉ |
| Radius | 0.205 R☉ |
| Luminosity | 0.005[4] L☉ |
| Temperature | 3,202±100[5] K |
| Metallicity [Fe/H] | −0.169[5] dex |
| Rotation | 132.651 days |
| Other designations | |
| Database references | |
| SIMBAD | data |
Gliese 754 is a dim star in the southern constellation of Telescopium. It has an apparent visual magnitude of 12.25,[2] which requires a telescope to view. The star is located at a distance of 19.3 light-years from the Sun based on parallax, and it is drifting further away with a radial velocity of +6 km/s.[1] It is one of the hundred closest stars to the Solar System. Calculations of its orbit around the Milky Way showed that it is eccentric, and indicate that it might be a thick disk object.[7]
The stellar classification of Gliese 754 is M4V,[2] indicating that this is a small red dwarf star on the core hydrogen fusing main sequence. It has 17% of the mass of the Sun and 21% of the Sun's radius.[3] The star is fully convective and is a source of X-ray emission.[8] It is rotating slowly with a period of about 133 days.[3] The metallicity is sub-solar,[5] indicating it has a lower abundance of heavy elements compared to the Sun. It is radiating just 0.5%[4] of the luminosity of the Sun from its photosphere at an effective temperature of around 3,202 K.[5]
Search for planets
In June 2019, a candidate exoplanet in orbit around Gliese 754 was reported in a preprint. It was detected using the Doppler method and is orbiting at a distance of 0.28 astronomical unit|AU with a period of 78 days. The orbit is essentially circular, to within the margin of error.[9] The habitable zone for this star ranges from 0.05 astronomical unit|AU to 0.14 AU;[4] inside the orbit of this proposed companion. However, a 2024 study could not confirm any planet around this star. A 77-day signal was detected, similar to the orbital period of this putative planet, but this may be caused by stellar activity.[10]
References
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 Vallenari, A. et al. (2022). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy & Astrophysics. doi:10.1051/0004-6361/202243940 Gaia DR3 record for this source at VizieR.
- ↑ 2.0 2.1 2.2 2.3 Henry, Todd J. et al. (2018). "The Solar Neighborhood XLIV: RECONS Discoveries within 10 parsecs". The Astronomical Journal 155 (6): 265. doi:10.3847/1538-3881/aac262. Bibcode: 2018AJ....155..265H.
- ↑ 3.0 3.1 3.2 Newton, Elisabeth R. et al. (November 2018). "New Rotation Period Measurements for M Dwarfs in the Southern Hemisphere: An Abundance of Slowly Rotating, Fully Convective Stars". The Astronomical Journal 156 (5): 11. doi:10.3847/1538-3881/aad73b. 217. Bibcode: 2018AJ....156..217N.
- ↑ 4.0 4.1 4.2 Mayor, M. et al. (2009). "The HARPS search for southern extra-solar planets. XIII. A planetary system with 3 Super-Earths (4.2, 6.9, & 9.2 Earth masses)". Astronomy and Astrophysics 493 (2): 639–644. doi:10.1051/0004-6361:200810451. Bibcode: 2009A&A...493..639M.
- ↑ 5.0 5.1 5.2 5.3 Houdebine, E. R. et al. (May 2016). "Rotation-Activity Correlations in K and M Dwarfs. I. Stellar Parameters and Compilations of v sin I and P/sin I for a Large Sample of Late-K and M Dwarfs". The Astrophysical Journal 822 (2): 38. doi:10.3847/0004-637X/822/2/97. 97. Bibcode: 2016ApJ...822...97H.
- ↑ "L 347-14". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=L+347-14.
- ↑ Innanen, K.A.; Flynn, C. (2010). "The Radial Velocity, Space Motion, and Galactic Orbit of GJ 754". Journal of the Royal Astronomical Society of Canada 104 (6): 223–24. Bibcode: 2010JRASC.104..223I.
- ↑ Wright, Nicholas J. et al. (September 2018). "The stellar rotation-activity relationship in fully convective M dwarfs". Monthly Notices of the Royal Astronomical Society 479 (2): 2351–2360. doi:10.1093/mnras/sty1670. Bibcode: 2018MNRAS.479.2351W.
- ↑ Tuomi, M.; Jones, H. R. A.; Butler, R. P.; Arriagada, P.; Vogt, S. S.; Burt, J.; Laughlin, G.; Holden, B.; Shectman, S. A.; Crane, J. D.; Thompson, I.; Keiser, S.; Jenkins, J. S.; Berdiñas, Z.; Diaz, M.; Kiraga, M.; Barnes, J. R. (2019). "Frequency of planets orbiting M dwarfs in the Solar neighbourhood". arXiv:1906.04644 [astro-ph.EP].
- ↑ Mignon, L. et al. (September 2024). "Radial velocity homogeneous analysis of M dwarfs observed with HARPS". Astronomy & Astrophysics 689: A32. doi:10.1051/0004-6361/202346570.
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