HD 123657
Template:Location mark Location of BY Boö (circled) | |
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Boötes |
| Right ascension | Template:RA[1] |
| Declination | Template:DEC[1] |
| Apparent magnitude (V) | Script error: No such module "val".[2][3] |
| Characteristics | |
| Evolutionary stage | AGB[4] |
| Spectral type | M4.5III[5] |
| U−B Template:Engvar | 1.66[6] |
| B−V Template:Engvar | 1.58[6] |
| R−I Template:Engvar | 1.66[6] |
| Variable type | LB[5] |
| Astrometry | |
| Radial velocity (Rv) | Script error: No such module "val".[7] km/s |
| Proper motion (μ) | RA: +11.443 mas/yr[1] Dec.: Script error: No such module "val". mas/yr[1] |
| Parallax (π) | 6.0110±0.1554 mas[1] |
| Distance | Template:Rnd ± Template:Rnd ly (Template:Rnd ± Template:Rnd pc) |
| Absolute magnitude (MV) | −0.90[8] |
| Details | |
| Mass | 3.96[9] Template:Solar mass |
| Radius | Script error: No such module "val".[10] Template:Solar radius |
| Luminosity | Script error: No such module "val".[11] Template:Solar luminosity |
| Surface gravity (log g) | 0.66[12] cgs |
| Temperature | Script error: No such module "val".[11] K |
| Metallicity [Fe/H] | −0.03[13] dex |
| Metallicity [Fe/H] | {{{metal_fe2}}} dex |
| Other designations | |
| BY Boötis, HD 123657, HIP 69038, HR 5299, GSC 03040-00969, TYC 3040-969-1, BD+44°2325, IRAS 14059+4405, IRC +40253, SAO 44901 | |
| Database references | |
| SIMBAD | data |
Script error: No such module "Check for unknown parameters".
HD 123657 (BY Boötis) is a star in the northern constellation of Boötes, near the end of the handle of the Big Dipper. It is a fifth-magnitude star, and can be spotted to the unaided eye in sufficiently dark skies, far from light pollution. Based on stellar parallax measurements, it is about 540 light-years distant.
This is a slow irregular variable with an apparent magnitude varying between 4.98 and 5.33.[2][3] The variability of the brightness of HD 123657 was announced by Joel Stebbins and Charles Morse Huffer in 1928, based on observations made at Washburn Observatory.[15] The star was given its variable star designation, BY Boötis, in 1973.[16]
HD 123657 has a spectral classification of M4.5III,[5] placing it as a cool red giant that exhausted its hydrogen supply. It has expanded to over 132 times the size of the Sun,[10] now radiating 1,600 times its luminosity at a cool photosphere that has an effective temperature of Script error: No such module "val"..[11]
References
<templatestyles src="Reflist/styles.css" />
- ↑ a b c d Template:Cite Gaia DR3
- ↑ a b Script error: No such module "Citation/CS1".
- ↑ a b Script error: No such module "citation/CS1".
- ↑ Script error: No such module "Citation/CS1".
- ↑ a b c Script error: No such module "Citation/CS1".
- ↑ a b c Script error: No such module "Citation/CS1".
- ↑ Script error: No such module "Citation/CS1".
- ↑ Script error: No such module "Citation/CS1".
- ↑ Script error: No such module "Citation/CS1".
- ↑ a b Script error: No such module "Citation/CS1".
- ↑ a b c Script error: No such module "Citation/CS1".
- ↑ Script error: No such module "Citation/CS1".
- ↑ Script error: No such module "Citation/CS1".
- ↑ Script error: No such module "citation/CS1".
- ↑ Script error: No such module "Citation/CS1".
- ↑ Script error: No such module "Citation/CS1".
Script error: No such module "Check for unknown parameters".