V1057 Cygni

V1057 Cygni

A visual band light curve for V1057 Cygni. The main plot shows the long-term variability, and the inset shows the short-term variability. Adapted from Kopatskaya et al. (2002)[1] and Clarke et al. (2005).[2]
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Cygnus
Right ascension 20h 58m 53.73367s[3]
Declination +44° 15′ 28.3847″[3]
Apparent magnitude (V) 12.43±0.03[4]
Characteristics
Spectral type F7/G3 I/IIe[5]
B−V color index 1.93[6]
Variable type FU Ori
Astrometry
Proper motion (μ) RA: −2.793[3] mas/yr
Dec.: −3.813[3] mas/yr
Parallax (π)1.0864 ± 0.0388 mas[3]
Distance3,000 ± 100 ly
(920 ± 30 pc)
Details
Radius16.2+1.2
−3.2[3] R☉
Luminosity38.3±2.0[3] L☉
Temperature3,565+414
−127[3] K
Other designations
V1057 Cyg, LkHα 190, AAVSO 2055+43[7]
Database references
SIMBADdata

V1057 Cygni is a suspected binary star[8] system in the northern constellation of Cygnus. It is a variable star of the FU Orionis-type, and was the second FU Orionis-type variable to be discovered. The system is located at a distance of approximately 3,000 light years from the Sun,[3] in the North America Nebula.[4] It has an apparent visual magnitude of around 12.4.[4]

The initial classification of the primary was as a young T Tauri star.[4] During 1969–1970 it underwent a nova-like outburst, increasing in brightness by five magnitudes and emitting a strong mass outflow. For the next ten years the brightness stayed at a plateau before decreasing rapidly in the mid–1990s, accompanied by a change in its spectrum. As of 2013, it is 1.5 magnitudes brighter than it was before the nova-like event.[8] The mass of FU Ori objects is estimated to be in the range of 0.3–0.7 M☉.[4]

A faint binary companion was discovered in 2016, and designated component B. It is located at a projected separation of 30±5 AU from the primary, with a possible orbital period of ~300 years. The 1970 outburst of the primary may have been caused by torque of its accretion disk by the companion.[4]

  1. ^ Cite error: The named reference Kopatskaya was invoked but never defined (see the help page).
  2. ^ Cite error: The named reference Clarke was invoked but never defined (see the help page).
  3. ^ a b c d e f g h i Cite error: The named reference GaiaDR2 was invoked but never defined (see the help page).
  4. ^ a b c d e f Cite error: The named reference Green2016 was invoked but never defined (see the help page).
  5. ^ Cite error: The named reference Herbig_et_al_2003 was invoked but never defined (see the help page).
  6. ^ Cite error: The named reference Zacharias2012 was invoked but never defined (see the help page).
  7. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  8. ^ a b Cite error: The named reference Kopatskaya2013 was invoked but never defined (see the help page).