Coordinates: Sky map 09h 21m 03s, +34° 23′ 33″

Alpha Lyncis

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α Lyncis
Location of α Lyncis (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Lynx
Right ascension 09h 21m 03.30021s[1]
Declination +34° 23′ 33.2134″[1]
Apparent magnitude (V) +3.14[2]
Characteristics
Evolutionary stage Giant star
Spectral type K7 III[3]
U−B color index +1.95[4]
B−V color index +1.55[4]
Astrometry
Radial velocity (Rv)37.15[5] km/s
Proper motion (μ) RA: −218.723 mas/yr[1]
Dec.: 16.555 mas/yr[1]
Parallax (π)14.7±0.18 mas[1]
Distance220.7+2.9
−2.6
 ly
(67.7+0.9
−0.8
 pc)[6]
Absolute bolometric
magnitude
 (Mbol)
–2.32 ± 0.13[7]
Details
Mass1.52±0.077[8] M
Radius58.15+0.73
−0.75
[9] R
Luminosity621.1±15.8[8] L
Surface gravity (log g)1.06±0.04[8] cgs
Temperature3,881±20[8] K
Metallicity [Fe/H]−0.26±0.05[8] dex
Rotational velocity (v sin i)6.4[5] km/s
Age1.4[10] Gyr
Other designations
40 Lyncis, HR 3705, HD 80493, BD+35°1979, HIP 45860, SAO 61414, FK5 352, NSV 4456, GC 12880[11]
Database references
SIMBADdata

Alpha Lyncis (α Lyn, α Lyncis) is the brightest star in the northern constellation of Lynx with an apparent magnitude of +3.13.[4] Unusually, it is the only star in the constellation that has a Bayer designation.[10] Based upon parallax measurements, this star is located about 220 light-years (67 parsecs) from the Earth.[1]

Characteristics

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This is a red giant star that has exhausted the hydrogen at its core and has evolved away from the main sequence. It has expanded to about 58 times the Sun's radius[9] and it is emitting roughly 621 times the luminosity of the Sun. The estimated effective temperature of the star's outer envelope is 3,881 K,[8] which is lower than the Sun's effective temperature of 5,778 K, and is giving Alpha Lyncis a red-orange hue that is characteristic of late K-type stars.[12]

Alpha Lyncis is a suspected small-amplitude red variable star[13] that changes apparent magnitude from +3.17 up to +3.12.[14] This variability pattern typically occurs in stars that have developed an inert carbon core surrounded by a helium-fusing shell, and suggests that Alpha Lyncis is starting to evolve into a Mira variable.[10]

References

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  1. ^ a b c d e Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value). Gaia DR3 record for this source at VizieR.
  2. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
  3. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
  4. ^ a b c Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
  5. ^ a b Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
  6. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value). Data about this star can be seen here.
  7. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value). For Mbol, see Table 1.
  8. ^ a b c d e f Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value). Alpha Lyncis' database entry at VizieR.
  9. ^ a b Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
  10. ^ a b c Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
  11. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
  12. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
  13. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).
  14. ^ Lua error in Module:Citation/CS1/Configuration at line 2172: attempt to index field '?' (a nil value).