HD 90089 (HR 4084; Gliese 392.1) is a star located in the northern circumpolar constellation Camelopardalis. With an apparent magnitude of 5.25,[2] it is faintly visible to the naked eye under ideal conditions. This star is located relatively close at a distance of 75 light years,[8] but is drifting away at a rate of almost 8 km/s.[5]
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Camelopardalis |
| Right ascension | 10h 31m 04.7079s[1] |
| Declination | +82° 33′ 31.146″[1] |
| Apparent magnitude (V) | 5.252±0.009[2] |
| Characteristics | |
| Spectral type | F4 V kF2 mF2[3] |
| U−B color index | –0.05[4] |
| B−V color index | 0.37[4] |
| Astrometry | |
| Radial velocity (Rv) | 7.9±0.9[5] km/s |
| Proper motion (μ) | RA: –86.133[1] mas/yr Dec.: +19.832[1] mas/yr |
| Parallax (π) | 43.4367 ± 0.5983 mas[1] |
| Distance | 75 ± 1 ly (23.0 ± 0.3 pc) |
| Absolute magnitude (MV) | 3.60[6] |
| Details | |
| Mass | 1.29[7] M☉ |
| Radius | 1.40+0.03 −0.06[8] R☉ |
| Luminosity | 3.36±0.02[8] L☉ |
| Surface gravity (log g) | 4.43±0.14[7] cgs |
| Temperature | 6,602+159 −69[8] K |
| Metallicity [Fe/H] | –0.26[2] dex |
| Rotational velocity (v sin i) | 56.2[2] km/s |
| Age | 1.074[7] Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
HD 90089 is an F4 main-sequence star with the calcium K-line and metallic lines of an F2 star.[3] Although the spectral type is of a form that would indicate an Am star, it is not listed in any of the major catalogues of chemically peculiar stars.[9] At present it has 1.29 times the mass of the Sun[7] and 1.4 times its radius. It radiates at 3.36 times the luminosity of the Sun from its photosphere at an effective temperature of 6,602 K,[8] which gives it a yellowish-white hue.
HD 90089's exact age depends on the method, with X-ray giving it a young age of only 300 million years.[2] David et al. gave it an age of 1.1 billion years,[7] significantly older than the previous solution; it spins rapidly with a projected rotational velocity of 56.2 km/s,[2] and has an M0 companion separated 13" away[10] and at approximately the same distance.[11]
An infrared excess has been detected around this star, most likely indicating the presence of a circumstellar disk at a radius of 145 AU. The temperature of this dust is 30 K.[2]
References
edit- ^ a b c d e Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
- ^ a b c d e f g Eiroa, C.; et al. (July 2013). "DUst around NEarby Stars. The survey observational results". Astronomy & Astrophysics. 555: A11. arXiv:1305.0155. Bibcode:2013A&A...555A..11E. doi:10.1051/0004-6361/201321050. S2CID 377244.
- ^ a b Gray, R. O.; Corbally, C. J.; Garrison, R. F.; McFadden, M. T.; Robinson, P. E. (October 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): 2048–2059. arXiv:astro-ph/0308182. Bibcode:2003AJ....126.2048G. doi:10.1086/378365. ISSN 0004-6256.
- ^ a b Johnson, H. L.; Mitchell, R. I.; Iriarte, B.; Wisniewski, W. Z. (1966). "UBVRIJKL Photometry of the Bright Stars". Communications of the Lunar and Planetary Laboratory. 4: 99–110. Bibcode:1966CoLPL...4...99J.
- ^ a b Gontcharov, G. A. (November 2006). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system". Astronomy Letters. 32 (11): 759–771. arXiv:1606.08053. Bibcode:2006AstL...32..759G. doi:10.1134/S1063773706110065. ISSN 1063-7737. S2CID 119231169.
- ^ Reiners, Ansgar (January 2006), "Rotation- and temperature-dependence of stellar latitudinal differential rotation", Astronomy and Astrophysics, 446 (1): 267–277, arXiv:astro-ph/0509399, Bibcode:2006A&A...446..267R, doi:10.1051/0004-6361:20053911, S2CID 8642707
- ^ a b c d e David, Trevor J.; Hillenbrand, Lynne A. (12 May 2015). "The Ages of Early-type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets". The Astrophysical Journal. 804 (2): 146. arXiv:1501.03154. Bibcode:2015ApJ...804..146D. doi:10.1088/0004-637X/804/2/146. ISSN 0004-637X.
- ^ a b c d e 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.
- ^ Renson, P.; Manfroid, J. (May 2009). "Catalogue of Ap, HgMn and Am stars". Astronomy and Astrophysics. 498 (3): 961–966. Bibcode:2009A&A...498..961R. doi:10.1051/0004-6361/200810788.
- ^ Mason, Brian D.; Wycoff, Gary L.; Hartkopf, William I.; Douglass, Geoffrey G.; Worley, Charles E. (December 2001). "The 2001 US Naval Observatory Double Star CD-ROM. I. The Washington Double Star Catalog". The Astronomical Journal. 122 (6): 3466–3471. Bibcode:2001AJ....122.3466M. doi:10.1086/323920. ISSN 0004-6256.
- ^ Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.