2 Cygni

2 Cygni
Observation data
Epoch J2000      Equinox J2000
Constellation Cygnus
Right ascension 19h 24m 07.57863s[1]
Declination +29° 37′ 16.7934″[1]
Apparent magnitude (V) 4.976[2]
Characteristics
Spectral type B3 IV[3]
B−V color index −0.117[2]
Astrometry
Radial velocity (Rv)−23.60±2.0[4] km/s
Proper motion (μ) RA: +12.022[1] mas/yr
Dec.: +12.173[1] mas/yr
Parallax (π)3.5657 ± 0.1692 mas[1]
Distance910 ± 40 ly
(280 ± 10 pc)
Absolute magnitude (MV)−2.06[4]
Details
Mass7.0±0.1[5] M☉
Radius5.6[6] R☉
Luminosity (bolometric)3,354[2] L☉
Surface gravity (log g)3.653±0.035[7] cgs
Temperature16,479±219[7] K
Metallicity [Fe/H]+0.03±0.05[8] dex
Rotational velocity (v sin i)137±8[7] km/s
Age36.6±0.5[5] Myr
Other designations
BD+29°3584, FK5 3550, GC 26785, HD 182568, HIP 95372, HR 7372, SAO 87159[9]
Database references
SIMBADdata

2 Cygni is a blue-white hued star in the northern constellation of Cygnus, located a few degrees from Albireo. It is a probable astrometric binary;[10] the visible component can be viewed with the naked eye, having an apparent visual magnitude of 4.976.[2] Based upon an annual parallax shift of 3.6 mas,[1] it is located roughly 910 light years from Earth. It has a peculiar velocity of 23 km/s and may be a runaway star[5] system.

The stellar classification of the primary is B3 IV,[3] matching a B-type subgiant star. It has seven[5] times the mass of the Sun and about 5.6[6] times the Sun's radius. The star is 37[5] million years old with a high rate of spin; it has a projected rotational velocity of 137 km/s.[7] It is radiating 3,354[2] times the Sun's luminosity from its photosphere at an effective temperature of 16,479 K.[7]

  1. ^ a b c d e f Cite error: The named reference GaiaDR2 was invoked but never defined (see the help page).
  2. ^ a b c d e Cite error: The named reference Hohle2010 was invoked but never defined (see the help page).
  3. ^ a b Cite error: The named reference Lesh1968 was invoked but never defined (see the help page).
  4. ^ a b Cite error: The named reference Anderson2012 was invoked but never defined (see the help page).
  5. ^ a b c d e Cite error: The named reference Tetzlaff2011 was invoked but never defined (see the help page).
  6. ^ a b Cite error: The named reference Fracassini2001 was invoked but never defined (see the help page).
  7. ^ a b c d e Cite error: The named reference Huang2008 was invoked but never defined (see the help page).
  8. ^ Cite error: The named reference gaspar2016 was invoked but never defined (see the help page).
  9. ^ Cite error: The named reference SIMBAD was invoked but never defined (see the help page).
  10. ^ Cite error: The named reference Eggleton2008 was invoked but never defined (see the help page).