V1331 Cygni

V1331 Cygni (also known as V1331 Cyg) is a young star in the constellation Cygnus. V1331 Cyg is located in the dark nebula LDN 981.^[4]

V1331 Cygni

V1331 Cygni as photographed by the Hubble Space Telescope
Observation data Epoch J2000      Equinox J2000
Constellation	Cygnus
Right ascension	21h 01m 09.20684s[1]
Declination	+50° 21′ 44.8033″[1]
Apparent magnitude (V)	11.99[2]
Characteristics
Spectral type	G7-K0IV[3]
Astrometry
Proper motion (μ)	RA: 0.980[1] mas/yr Dec.: −3.783[1] mas/yr
Parallax (π)	1.6760±0.0237 mas[1]
Distance	1,950 ± 30 ly (597 ± 8 pc)
Details[3]
Mass	2.8 M☉
Radius	5 R☉
Temperature	5200 K
Other designations
V1331 Cyg, GSC 03596-00959, 2MASS J21010920+5021445
Database references
SIMBAD	data

V1331 Cygni is most noted for having an arc-like reflection nebula surrounding it. This circumstellar disc is a great birthplace for young stars, which form in the cloud.^[5] V1331 Cygni is heavily obscured by dust, so the properties of the central star are hard to deduce; however, it is estimated to have a radius five times that of the Sun and a mass of 2.8 M_☉.^[3]

Six visual band light curves for V1331 Cygni, adapted from Mel'nikov (1997)^[6]

The General Catalog of Variable Stars classifies V1331 Cygni as an "INST" type variable, meaning a T Tauri star which shows rapid light variations.^[7][8] Its visual band brightness varies from magnitude 13.08 to 10.58.^[7] It is sometimes classified as a pre-FUOR star.^[9] A semi-regular period of ~449 days has been reported.^[9] Unlike many T Tauri stars, the mean brightness of V1331 Cygni remains nearly constant over long time periods.^[10][6]

Gallery

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  Dark nebula LDN 981 and V1331 Cygni (top center) by the Mount Lemmon SkyCenter