HD 28700 (HR 1433) is a solitary star in the southern constellation Caelum. It has an apparent magnitude of 6.12,[2] making it visible to the naked eye under ideal conditions. Parallax measurements place the object at a distance of 384 light years[1] and is currently receding with a heliocentric radial velocity of 10.7 km/s.[5]
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Caelum |
| Right ascension | 04h 29m 20.0860s[1] |
| Declination | −46° 30′ 54.9738″[1] |
| Apparent magnitude (V) | 6.12±0.01[2] |
| Characteristics | |
| Evolutionary stage | red giant branch[1] |
| Spectral type | K1 III[3] |
| B−V color index | +1.06[4] |
| Astrometry | |
| Radial velocity (Rv) | 10.7±0.4[5] km/s |
| Proper motion (μ) | RA: +51.283 mas/yr[1] Dec.: +36.503 mas/yr[1] |
| Parallax (π) | 8.4964 ± 0.0265 mas[1] |
| Distance | 384 ± 1 ly (117.7 ± 0.4 pc) |
| Absolute magnitude (MV) | +0.69[6] |
| Details | |
| Mass | 3.0[1] M☉ |
| Radius | 10.5[1] R☉ |
| Luminosity | 56±2[7] L☉ |
| Surface gravity (log g) | 2.61[1] cgs |
| Temperature | 4,760±90[7] K |
| Metallicity [Fe/H] | +0.08[8] dex |
| Rotational velocity (v sin i) | <1[9] km/s |
| Age | 377[1] Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
HD 28700 has a stellar classification of K1 III,[3] indicating that it is a red giant. It has three times the Sun's mass and has expanded to ten times its radius. It radiates at 56 times the Sun's luminosity from its swollen photosphere at an effective temperature of 4,760 K,[7] giving it an orange hue. HD 28700 has a projected rotational velocity too low to be measured accurately due to it being less than 1 km/s.[9] HD 28700 has 120% the abundance of iron relative to the Sun.[8] At a modeled age of 377 million years, HD 28700 is on the red giant branch fusing hydrogen in a shell around an inert helium core.[1]
References
edit- ^ a b c d e f g h i j k 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 Høg, E.; Fabricius, C.; Makarov, V. V.; Urban, S.; Corbin, T.; Wycoff, G.; Bastian, U.; Schwekendiek, P.; Wicenec, A. (March 2000). "The Tycho-2 catalogue of the 2.5 million brightest stars". Astronomy and Astrophysics. 355: L27–L30. Bibcode:2000A&A...355L..27H. ISSN 0004-6361.
- ^ a b Houk, Nancy (1978). "Michigan catalogue of two-dimensional spectral types for the HD stars". Ann Arbor: Dept. Of Astronomy. Bibcode:1978mcts.book.....H.
- ^ 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.
- ^ Anderson, E.; Francis, Ch. (May 2012). "XHIP: An extended hipparcos compilation". Astronomy Letters. 38 (5): 331–346. arXiv:1108.4971. Bibcode:2012AstL...38..331A. doi:10.1134/S1063773712050015. ISSN 1063-7737. S2CID 119257644.
- ^ a b c Charbonnel, C.; Lagarde, N.; Jasniewicz, G.; North, P. L.; Shetrone, M.; Krugler Hollek, J.; Smith, V. V.; Smiljanic, R.; Palacios, A.; Ottoni, G. (January 2020). "Lithium in red giant stars: Constraining non-standard mixing with large surveys in the Gaia era". Astronomy & Astrophysics. 633: A34. arXiv:1910.12732. Bibcode:2020A&A...633A..34C. doi:10.1051/0004-6361/201936360. eISSN 1432-0746. ISSN 0004-6361.
- ^ a b Eggen, O. J. (February 1994). "Evolved GK stars near the Sun. 2: The young disk population". The Astronomical Journal. 107: 594. Bibcode:1994AJ....107..594E. doi:10.1086/116879. ISSN 0004-6256.
- ^ a b De Medeiros, J. R.; Alves, S.; Udry, S.; Andersen, J.; Nordström, B.; Mayor, M. (January 2014). "A catalog of rotational and radial velocities for evolved stars: V. Southern stars⋆⋆⋆". Astronomy & Astrophysics. 561: A126. arXiv:1312.3474. Bibcode:2014A&A...561A.126D. doi:10.1051/0004-6361/201220762. ISSN 0004-6361.
- ^ "HD 28700". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved June 17, 2022.
- ^ Gould, Benjamin Apthorp (1878). "Uranometria Argentina: brillantez y posicion de las estrellas fijas, hasta la septima magnitud, comprendidas dentro de cien grados del polo austral: con atlas". Resultados del Observatorio Nacional Argentino. 1. Bibcode:1879RNAO....1.....G.