HD 123657

HD 123657

HD 123657
Observation data Epoch J2000      Equinox J2000
Constellation	Boötes
Right ascension	01h 09m 43.9s
Declination	+35° 37′ 14″
Apparent magnitude (V)	2.07
Characteristics
Spectral type	M4.5:III
U−B color index	1.66
B−V color index	1.59
R−I color index	1.66
Variable type	Variable star (171)
Astrometry
Radial velocity (Rv)	-35.8 km/s
Proper motion (μ)	RA: 11.73 mas/yr Dec.: -29.76 mas/yr
Parallax (π)	7.01 ± 0.66 mas
Distance	470 ± 40 ly (140 ± 10 pc)
Absolute magnitude (MV)	6.71
Details
Mass	0,4 M☉
Radius	0,5 R☉
Luminosity	0,04 L☉
Temperature	2,000–3,500 K
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
Data sources:
Hipparcos Catalogue, CCDM (2002), Bright Star Catalogue (5th rev. ed.)

HD 123657, or BY Boötis, is a variable star. Its variability spectral is 4.98–5.33V. It has slow, irregular variables of late spectral types (K, M, C, S); as a rule, they are giants (CO Cyg). This type is also ascribed, in the GCVS, to slow red irregular variables in the case of unknown spectral types and luminosities. Alcyone.de: HR5299^{[not in citation given]} It is hypothetical.

References

• HR 5299
• Image HD 123657