A visual band light curve for WY Geminorum, plotted from ASAS-SN data[1]
Observation data Epoch J2000.0 Equinox J2000.0
Constellation
Gemini[2]
Right ascension
06h 11m 56.250s[3]
Declination
+23° 12′ 25.41″[3]
Apparent magnitude (V)
7.263 to 7.513[4]
Characteristics
Spectral type
M2Ia-b + B2V[5]
B−V color index
1.517±0.017[2]
Variable type
Irregular variable + eclipsing binary[6]
Astrometry
Radial velocity (Rv)
19.52±0.22[7] km/s
Proper motion (μ)
RA: 0.450 mas/yr[3] Dec.: −2.380 mas/yr[3]
Parallax (π)
0.5169 ± 0.0343 mas[3]
Distance
6,300 ± 400 ly (1,900 ± 100 pc)
Orbit[5]
Period (P)
64.48 ± 0.68 yr
Semi-major axis (a)
≥ (4.09±0.19)×109 km
Eccentricity (e)
0.61±0.03
Periastron epoch (T)
2,445,620±130 JD
Argument of periastron (ω) (secondary)
57.5±4.5°
Semi-amplitude (K1) (primary)
16.0±0.9 km/s
Details
Primary
Radius
522+45 −34[8]R☉
Surface gravity (log g)
0.70[9] cgs
Temperature
3,789[9] K
Metallicity [Fe/H]
−0.36[9] dex
Other designations
WY Gem, BD+23° 1243, HD 42474, HIP 29425, SAO 78094, PPM 95591[10]
Database references
SIMBAD
data
WY Geminorum is a binary star system in the northern constellation of Gemini, abbreviated WY Gem. It has an apparent visual magnitude that ranges from 7.26 down to 7.51,[4] which is too faint to be readily viewed with the naked eye. This system is located at a distance of approximately 6,300 light years from the Sun based on parallax measurements, and is receding with a radial velocity of 19.5 km/s.[7]
In 1922, M. L. Humason found the spectrum of HD 42474 matches an M-type star, but with the peculiarity of numerous bright lines. It appears similar to the spectrum of VV Cephei (HR 8383), an eclipsing binary.[11] P. Swings and O. Struve in 1941 discovered emission lines in the ultraviolet spectrum.[12] The presence of a B-type stellar spectrum from a companion star was confirmed by W. P. Bidelman in 1954. The primary spectrum matches an M-type supergiant star.[13] A. Cowley in 1970 found evidence of an atmospheric eclipse of the companion.[14] In 1981, A. Buzzoni determined the primary to be a semi-regular variable of the SRb type with a period of 169 days.[15]
This is a double-lined spectroscopic binary star system with an approximate orbital period of 64.48 ± 0.68 years and a high eccentricity (ovalness) of 0.61. The primary component is an M-type supergiant star with a stellar classification of M2Ia or b. The companion is most likely a hotter B-type main-sequence star with a class of B2V.[5] The pair are classified as a VV Cephei-type star system. The companion may be accreting matter from the supergiant around the time of periastron passage, resulting in the formation of an intermittent accretion disk orbiting the hotter star.[5] Radio emission has been detected, which is most likely coming from an ionized region in the stellar wind of the supergiant.[16]
^Cite error: The named reference ASAS-SN was invoked but never defined (see the help page).
^ abCite error: The named reference Anderson_Francis_2012 was invoked but never defined (see the help page).
^ abcdCite error: The named reference GaiaDR3 was invoked but never defined (see the help page).
^ abCite error: The named reference Laur_et_al_2017 was invoked but never defined (see the help page).
^ abcdCite error: The named reference Leedjaerv_1998 was invoked but never defined (see the help page).
^Cite error: The named reference Samus_et_al_2017 was invoked but never defined (see the help page).
^ abCite error: The named reference GaiaDR2 was invoked but never defined (see the help page).
^Cite error: The named reference Norris2023 was invoked but never defined (see the help page).
^ abcCite error: The named reference Cenarro_et_al_2007 was invoked but never defined (see the help page).
^Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
^Cite error: The named reference Humason_1922 was invoked but never defined (see the help page).
^Cite error: The named reference Swings_Struve_1941 was invoked but never defined (see the help page).
^Cite error: The named reference Martini_1969 was invoked but never defined (see the help page).
^Cite error: The named reference Cowley_1970 was invoked but never defined (see the help page).
^Cite error: The named reference Buzzoni_1981 was invoked but never defined (see the help page).
^Cite error: The named reference Hjellming_1985 was invoked but never defined (see the help page).
WYGeminorum is a binary star system in the northern constellation of Gemini, abbreviated WY Gem. It has an apparent visual magnitude that ranges from...
visible with binoculars, found southeast of M 35, just to the south of WYGeminorum. It is moving further from the Earth with a heliocentric radial velocity...
Nu Geminorum, Latinized from ν Geminorum, is a triple star system in the constellation Gemini. It has an apparent visual magnitude of 4.16, which is bright...
Sigma Geminorum (σ Gem) is a binary star system in the constellation Gemini, just to the northwest of Pollux. It is visible to the naked eye with an apparent...
Kappa Geminorum (κ Geminorum, κ Gem) is a binary star system in the northern zodiac constellation of Gemini. It is visible to the naked eye with an apparent...
Omicron Geminorum (ο Geminorum, abbreviated Omicron Gem, ο Gem), also named Jishui, is a solitary star in the constellation of Gemini. It is faintly visible...
Iota Geminorum (ι Geminorum, ι Gem) is a solitary fourth-magnitude star in the constellation Gemini. In the sky, it forms an isosceles triangle with Castor...
Theta Geminorum (θ Gem, θ Geminorum) is a single star in the northern zodiac constellation of Gemini. It is visual to the naked eye with an apparent visual...
Upsilon Geminorum, Latinized from υ Geminorum, is a star in the constellation Gemini. It has an apparent visual magnitude of 4.04, which is bright enough...
Chi Geminorum (χ Gem) is a binary star system in the constellation Gemini, near the eastern border with Cancer. It can be viewed with the naked eye on...
π Geminorum (Latinised as Pi Geminorum, abbreviated to π Gem or pi Gem) is a star located in the constellation Gemini, to the north of Castor. With an...
Phi Geminorum, Latinized from φ Geminorum, is a binary star in the constellation Gemini, to the southeast of Pollux. It is visible to the naked eye with...
Omega Geminorum, Latinized from ω Geminorum, is a star located in the middle of the northern zodiac constellation of Gemini. With an apparent visual magnitude...
Bibcode:2005A&A...438..273V. doi:10.1051/0004-6361:20042555. S2CID 16724272. "GCVS: "==WY Vel"". VizieR. General Catalogue of Variable Stars @ Centre de données astronomiques...