| |
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Boötes |
| Right ascension | 14h07m 55.756s[1] |
| Declination | 43° 51′ 16.03″[1] |
| Apparent magnitude (V) | 5.28[2] (4.98-5.33[3]) |
| Characteristics | |
| Spectral type | M4.5III[4] |
| U−B color index | 1.66[2] |
| B−V color index | 1.58[2] |
| R−I color index | 1.66[2] |
| Variable type | LB[4] |
| Astrometry | |
| Radial velocity (Rv) | -36.24[5] km/s |
| Proper motion (μ) | RA: 11.63[1] mas/yr Dec.: -30.08[1] mas/yr |
| Parallax (π) | 6.36 ± 0.26 mas[1] |
| Distance | 510 ± 20 ly (157 ± 6 pc) |
| Absolute magnitude (MV) | −0.90[6] |
| Details | |
| Radius | 70[7] R☉ |
| Luminosity | 1,380[8] L☉ |
| Temperature | 3,500[8] K |
| Metallicity [Fe/H] | −0.03[9] dex |
| Other designations | |
BY Boötis, JP11 2471, AG+44° 1162, GSC 03040-00969, 2MASS J14075576+4351160, TYC 3040-969-1, BD+44° 2325, HD 123657, N30 3210, UBV M 19995, CSV 7099, HIC 69038, PLX 3214, UBV 12478, DO 34564, HIP 69038, PMC 90-93 957, FK5 1368, HR 5299, PPM Star Catalogue 53940, GC 19084, IRAS 14059+4405, RAFGL 1680, AAVSO 1403+44, GCRV 8285, IRC +40253, SAO 44901. | |
| Database references | |
| SIMBAD | data |
HD 123657, or BY Boötis, is a variable star of magnitude 4.98–5.33V. This makes it a dim naked eye star. The star is located near the end of the handle of the Big Dipper, but just within the boundaries of the constellation Boötes.
It is a slow irregular red giant variable star with a range of less than half a magnitude. It is over a thousand times as luminous as the sun, only 3,500 K but with a large expanded atmosphere.
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 | This giant-star-related article is a stub. You can help Wikipedia by expanding it. |
