  | |
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Equuleus |
| Right ascension | 21h 15m 49.43192s[1] |
| Declination | +05° 14′ 52.2430″[1] |
| Apparent magnitude (V) | +3.919[2](4.49/4.96) |
| Characteristics | |
| Spectral type | G7III + kA3hA4mA9[3] |
| U−B color index | +0.284[2] |
| B−V color index | +0.529[2] |
| Astrometry | |
| Radial velocity (Rv) | −15.71 ± 0.05[3] km/s |
| Proper motion (μ) | RA: +59.88 ± 0.23[1] mas/yr Dec.: −94.09 ± 0.18[1] mas/yr |
| Parallax (π) | 17.14 ± 0.21 mas[1] |
| Distance | 190 ± 2 ly (58.3 ± 0.7 pc) |
| Absolute magnitude (MV) | +0.17 (0.71 + 1.18)[3] |
| Orbit[3] | |
| Period (P) | 98.8098 days |
| Eccentricity (e) | 0 |
| Semi-amplitude (K1) (primary) | 16.34 ± 0.07 km/s |
| Semi-amplitude (K2) (secondary) | 17.9 ± 0.3 km/s |
| Details | |
| A | |
| Mass | 2.3[3] M☉ |
| Radius | 9.2[3] R☉ |
| Luminosity | 52.5[3] L☉ |
| Temperature | 5,100[3] K |
| Rotational velocity (v sin i) | 20.0[4] km/s |
| B | |
| Mass | 2.0[3] M☉ |
| Radius | 2.6[3] R☉ |
| Luminosity | 26.3[3] L☉ |
| Temperature | 8.150[3] K |
| Age | 740[3] Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
Alpha Equulei (α Equulei, abbreviated Alpha Equ, α Equ), officially named Kitalpha /kɪˈtælfə/,[5][6] is a star in the constellation of Equuleus. It is a high proper-motion star only 190 light-years away.
- ^ a b c d e van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics. 474 (2): 653–664. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357. S2CID 18759600.Vizier catalog entry
- ^ a b c Cousins, A. W. J. (1984). "Standardization of Broadband Photometry of Equatorial Standards". South African Astronomical Observatory Circulars. 8: 59. Bibcode:1984SAAOC...8...59C.
- ^ a b c d e f g h i j k l m Griffin, R. E. M.; Griffin, R. F. (2002). "Composite spectra Paper 11: α Equulei, an astrometric binary with an Am secondary". Monthly Notices of the Royal Astronomical Society. 330 (2): 288. Bibcode:2002MNRAS.330..288G. doi:10.1046/j.1365-8711.2002.05030.x.
- ^ Cite error: The named reference
aaa361_614was invoked but never defined (see the help page). - ^ Kunitzsch, Paul; Smart, Tim (2006). A Dictionary of Modern star Names: A Short Guide to 254 Star Names and Their Derivations (2nd rev. ed.). Cambridge, Massachusetts: Sky Pub. ISBN 978-1-931559-44-7.
- ^ "IAU Catalog of Star Names". Retrieved 28 July 2016.