Observation data Epoch J2000 Equinox J2000 |
|
---|---|
Constellation | Lynx |
Right ascension | 07h 28m 11.61802s |
Declination | +45° 59′ 26.2366″ |
Apparent magnitude (V) | 6.2 - 8.9 |
Characteristics | |
Spectral type | M6S Ib |
Variable type | SRc |
Astrometry | |
Radial velocity (Rv) | 5.50 ± 0.6 km/s |
Proper motion (μ) |
RA: 0.23 ± 1.17 mas/yr Dec.: −3.41 ± 0.60 mas/yr |
Parallax (π) | 3.95 ± 0.95mas |
Distance | approx. 800 ly (approx. 250 pc) |
Details | |
Mass | 1.5 - 2.0 M☉ |
Radius | 580 R☉ |
Luminosity | 10,765 L☉ |
Surface gravity (log g) | 0.0 cgs |
Temperature | 3,200 K |
Metallicity [Fe/H] | −0.19 dex |
Other designations | |
Y Lyncis is a semiregular variable star in the constellation Lynx. It is an asymptotic giant branch star of spectral type M6S, with a luminosity class of Ib, indicating a supergiant luminosity. It is around 800 light years away.
Y Lyncis ranges in brightness from magnitude 6.8 to 8.9. Its changes in brightness are complex with at least two different periods showing. The General Catalogue of Variable Starslists a period of 110 days. More recent studies show a primary pulsation period of 133 days, with and a long secondary period with an amplitude of 0.2 magnitudes and duration 1,300 days. The long secondary period variations are possibly caused by long-lived convection cells.
Y Lyncis has a mass around 1.5-2.0 M☉ and a luminosity around 10,000 L☉. It is a thermally pulsing asymptotic giant branch star, an evolved star with a carbon-oxygen core that is fusing helium in a shell and hydrogen in a separate shell. It is also an S-type star, where third dredge-ups have brought some carbon to the surface, but not enough to create a carbon star.