Astronomy:7 Andromedae
| Observation data Equinox J2000.0]] (ICRS) | |
|---|---|
| Constellation | Andromeda[1] |
| Right ascension | 23h 12m 33.004s[2] |
| Declination | +49° 24′ 22.35″[2] |
| Apparent magnitude (V) | 4.52[3] |
| Characteristics | |
| Spectral type | F1V[4] |
| U−B color index | +0.01[5] |
| B−V color index | +0.28[5] |
| Astrometry | |
| Radial velocity (Rv) | 12.10±1[6] km/s |
| Proper motion (μ) | RA: 89.939[2] mas/yr Dec.: 95.704[2] mas/yr |
| Parallax (π) | 40.2940 ± 0.1130[2] mas |
| Distance | 80.9 ± 0.2 ly (24.82 ± 0.07 pc) |
| Absolute magnitude (MV) | 2.58[1] |
| Details[7] | |
| Mass | 1.6±0.1 M☉ |
| Radius | 1.71±0.02 R☉ |
| Luminosity | 7.8±0.6 L☉ |
| Surface gravity (log g) | 4.16±0.02 cgs |
| Temperature | 7,380±90 K |
| Metallicity [Fe/H] | −0.02±0.08 dex |
| Rotational velocity (v sin i) | 61±6 km/s |
| Age | 1,120±30 Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
7 Andromedae, also named Honores,[9] is a single,[10] yellow-white hued star in the northern constellation of Andromeda. 7 Andromedae is the Flamsteed designation, abbreviated 7 And. It is visible to the naked eye with an apparent visual magnitude of 4.52,[3] and is located 80.9 light years from Earth, based on an annual parallax shift of 40.3 mas.[2] The star is moving further from the Sun with a heliocentric radial velocity of 12 km/s.[6]
This is an ordinary F-type main-sequence star with a stellar classification of F1V,[4] which indicates it is generating energy from hydrogen fusion at its core. This energy is being radiated from its photosphere at the rate of 7.8 times the Sun's luminosity with an effective temperature of 7,380 K. The star has 1.6 times the mass of the Sun and 1.7 times the Sun's girth. 7 Andromedae is 1.1 billion years old and is spinning with a projected rotational velocity of 61 km/s.[7]
Within Andromeda it is at the middle of a northerly chain asterism – 8, 11 are further south-westward, with 5, then 3 Andromedae in the other direction. This star is the closest of these five, all of quite great apparent magnitude.
This star was part of the historical constellation Honores Friderici. The IAU Working Group on Star Names approved the name Honores for this star on 14 May 2025, after the obsolete constellation, and it is now so entered in the IAU Catalog of Star Names. This star was chosen for the name because it was in the feather part of the constellation, in reference to the proverb "the feather is mightier than the sword".[9]
References
- ↑ 1.0 1.1 Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters 38 (5): 331. doi:10.1134/S1063773712050015. Bibcode: 2012AstL...38..331A.
- ↑ 2.0 2.1 2.2 2.3 2.4 Brown, A. G. A. (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics 649: A1. doi:10.1051/0004-6361/202039657. Bibcode: 2021A&A...649A...1G. Gaia EDR3 record for this source at VizieR.
- ↑ 3.0 3.1 Ducati, J. R. (2002). "VizieR Online Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system". CDS/ADC Collection of Electronic Catalogues 2237. Bibcode: 2002yCat.2237....0D.
- ↑ 4.0 4.1 Gray, R. O.; Corbally, C. J.; Garrison, R. F.; McFadden, M. T.; Robinson, P. E. (2003). "Contributions to the Nearby Stars (NStars) Project: Spectroscopy of Stars Earlier than M0 within 40 Parsecs: The Northern Sample. I". The Astronomical Journal 126 (4): 2048. doi:10.1086/378365. Bibcode: 2003AJ....126.2048G.
- ↑ 5.0 5.1 Mermilliod, J.-C. (1986). "Compilation of Eggen's UBV data, transformed to UBV (unpublished)". Catalogue of Eggen's UBV Data: 0. Bibcode: 1986EgUBV........0M. http://cdsads.u-strasbg.fr/cgi-bin/nph-bib_query?1986EgUBV........0M&db_key=AST&nosetcookie=1.
- ↑ 6.0 6.1 Gontcharov, G. A. (2006). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system". Astronomy Letters 32 (11): 759–771. doi:10.1134/S1063773706110065. Bibcode: 2006AstL...32..759G.
- ↑ 7.0 7.1 Maestro, V.; Che, X.; Huber, D.; Ireland, M. J.; Monnier, J. D.; White, T. R.; Kok, Y.; Robertson, J. G. et al. (2013). "Optical interferometry of early-type stars with PAVO@CHARA - I. Fundamental stellar properties". Monthly Notices of the Royal Astronomical Society 434 (2): 1321. doi:10.1093/mnras/stt1092. Bibcode: 2013MNRAS.434.1321M.
- ↑ "7 And". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=7+And.
- ↑ 9.0 9.1 "IAU Catalog of Star Names". https://exopla.net/star-names/modern-iau-star-names/.
- ↑ Eggleton, P. P.; Tokovinin, A. A. (September 2008), "A catalogue of multiplicity among bright stellar systems", Monthly Notices of the Royal Astronomical Society 389 (2): 869–879, doi:10.1111/j.1365-2966.2008.13596.x, Bibcode: 2008MNRAS.389..869E.
