A visual band light curve for Y Lyncis, adapted from Percy et al. (2001). [1] The top panel shows the brightness variation over a period of several years, and the lower panel shows shorter time scale variations. | |
Observation data Epoch J2000 Equinox J2000 | |
---|---|
Constellation | Lynx |
Right ascension | 07h 28m 11.61657s [2] |
Declination | +45° 59′ 26.2295″ [2] |
Apparent magnitude (V) | 6.2 - 8.9 [3] |
Characteristics | |
Spectral type | M6S Ib [4] |
Variable type | SRc [4] |
Astrometry | |
Radial velocity (Rv) | 5.50±0.6 [5] km/s |
Proper motion (μ) | RA: −1.278 [2] mas/yr Dec.: −4.067 [2] mas/yr |
Parallax (π) | 2.8068 ± 0.1138 mas [2] |
Distance | 1,160 ± 50 ly (360 ± 10 pc) |
Details | |
Mass | 1.5 - 2.0 [3] M☉ |
Radius | 580 [3] R☉ |
Luminosity | 10,765 [6] L☉ |
Surface gravity (log g) | 0.0 [7] cgs |
Temperature | 3,200 [7] K |
Metallicity [Fe/H] | −0.19 [7] dex |
Other designations | |
Database references | |
SIMBAD | data |
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 1,160 light years away.
Y Lyncis ranges in brightness from magnitude 6.2 to 8.9. Its changes in brightness are complex with at least two different periods showing. The General Catalogue of Variable Stars lists a period of 110 days. [8] 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. [9]
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. [10] 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. [6]
Zeta Puppis, formally named Naos, is a star in the constellation of Puppis.
Alpha Cygni variables are variable stars which exhibit non-radial pulsations, meaning that some portions of the stellar surface are contracting at the same time other parts expand. They are supergiant stars of spectral types B or A. Variations in brightness on the order of 0.1 magnitudes are associated with the pulsations, which often seem irregular, due to beating of multiple pulsation periods. The pulsations typically have periods of several days to several weeks.
NO Aurigae is a pulsating variable star in the constellation Auriga. It is an unusually-luminous asymptotic giant branch star about 3,500 light years away.
6 Cassiopeiae is a white hypergiant in the constellation Cassiopeia, and a small-amplitude variable star.
V381 Cephei is a triple star system in the northern constellation of Cepheus. Its apparent magnitude is slightly variable between 5.5 and 5.7.
HD 33579 is a white/yellow hypergiant and one of the brightest stars in the Large Magellanic Cloud (LMC). It is a suspected variable star.
55 Cygni is a blue supergiant star in the constellation Cygnus. It is thought to be a member of the Cygnus OB7 stellar association at about 2,700 light years.
Sigma Ophiuchi, Latinized from σ Ophiuchi, is a single, orange-hued star in the equatorial constellation Ophiuchus. Its apparent visual magnitude is 4.31, which is bright enough to be faintly visible to the naked eye. The annual parallax shift of 3.62 mas as seen from Earth provides a distance estimate of roughly 900 light years. It is moving closer to the Sun with a radial velocity of −28 km/s.
V1073 Scorpii is a variable star in the constellation Scorpius. It has a non-Greek Bayer designation of k Scorpii. The star has a blue-white hue and is visible to the naked eye with an apparent visual magnitude that fluctuates around +4.87. Parallax measurements yield a distance estimate of approximately 2,920 ly (896 pc) from the Sun, and it is drifting further away with a radial velocity of +7 km/s. It has an absolute magnitude of −6.8
HDE 316285 is a blue supergiant star in the constellation Sagittarius. It is a candidate luminous blue variable and lies about 6,000 light years away in the direction of the galactic centre.
3 Geminorum is a blue supergiant star in the constellation Gemini. It is a small amplitude pulsating variable and a close double star, with a mean combined apparent visual magnitude of about 5.7.
TW Horologii is a carbon star and semiregular variable in the southern constellation of Horologium, near the eastern constellation border with Reticulum. It has a ruddy hue and, with an apparent visual magnitude that ranges from 5.52 down to 5.95, is visible to the naked eye and one of the brightest carbon stars. Based on parallax measurements, it is located at a distance of approximately 1,370 light years from the Sun. It is drifting further away with a radial velocity of +14 km/s. In the past this star has been considered a member of the open cluster NGC 1252, but this now seems unlikely.
V915 Scorpii is an orange hypergiant variable star in the constellation Scorpius.
TV Geminorum is a variable red supergiant in the constellation Gemini. Its visual magnitude varies from 6.3 to 7.5.
DS Crucis is a variable star near the open cluster NGC 4755, which is also known as the Kappa Crucis Cluster or Jewel Box Cluster. It is in the constellation Crux.
S Cassiopeiae is a Mira variable and S-type star in the constellation Cassiopeia. It is an unusually cool star, rapidly losing mass and surrounded by dense gas and dust producing masers.
BO Carinae, also known as HD 93420, is an irregular variable star in the constellation Carina.
DU Crucis is a red supergiant and slow irregular variable star in the open cluster NGC 4755, which is also known as the Kappa (κ) Crucis Cluster or Jewel Box Cluster.
II Lupi is a Mira variable and carbon star located in the constellation Lupus. It is the brightest carbon star in the southern hemisphere at 12 μm.