Universe Guide


V2140 Cygni, HD199478, HIP103312

V2140 Cygni is a blue eruptive very luminous supergiant star that can be located in the constellation of Cygnus. V2140 Cygni is the brightest star in Cygnus based on the Hipparcos 2007 apparent magnitude. The star can be seen with the naked eye, that is, you don't need a telescope/binoculars to see it.

HIP103312 is the reference name for the star in the Hipparcos Star Catalogue. The Id of the star in the Henry Draper catalogue is HD199478.

V2140 Cygni has alternative name(s), V2140 Cyg.

Location of V2140 Cygni

The location of the star in the galaxy is determined by the Right Ascension (R.A.) and Declination (Dec.), these are equivalent to the Longitude and Latitude on the Earth. The Right Ascension is how far expressed in time (hh:mm:ss) the star is along the celestial equator. If the R.A. is positive then its eastwards. The Declination is how far north or south the star is compared to the celestial equator and is expressed in degrees. For V2140 Cygni, the location is 20h 55m 49.81 and +47d25`03.6 .

V2140 Cygni Luminosity

Luminosity is the amount of energy that a star pumps out and its relative to the amount that our star, the Sun gives out. The figure of 73000.0000000 that I have given is based on the Spectral Types page that I have found on the Internet. You might find a different figure, one that may have been calculated rather than generalised that I have done. The figure is always the amount times the luminosity of the Sun. It is an imprecise figure because of a number of factors including but not limited to whether the star is a variable star and distance.

Physical Properties (Colour, Temperature, Radius) of V2140 Cygni

V2140 Cygni has a spectral type of B8Ia. This means the star is a blue supergiant star. The star has a B-V Colour Index of 0.4 which means the star's temperature has been calculated using information from Morgans @ Uni.edu at being 6,398 Kelvin.

V2140 Cygni Radius has been calculated as being 158.81 times bigger than the Sun.The Sun's radius is 695,800km, therefore the star's radius is an estimated 110,500,477.43.km. The figure is derived at by using the formula from SDSS and has been known to produce widely incorrect figures. The star's Iron Abundance is -0.14 with an error value of 9.99 Fe/H with the Sun has a value of 1 to put it into context.

V2140 Cygni Apparent and Absolute Magnitudes

V2140 Cygni has an apparent magnitude of 5.68 which is how bright we see the star from Earth. Apparent Magnitude is also known as Visual Magnitude. If you used the 1997 Parallax value, you would get an absolute magnitude of -6.60 Magnitude, whether it be apparent/visual or absolute magnitude is measured by a number, the smaller the number, the brighter the Star is. Our own Sun is the brightest star and therefore has the lowest of all magnitudes, -26.74. A faint star will have a high number.

Distance to V2140 Cygni

Using the original Hipparcos data that was released in 1997, the parallax to the star was given as 0.35 which gave the calculated distance to V2140 Cygni as 9318.95 light years away from Earth or 2857.14 parsecs. It would take a spaceship travelling at the speed of light, 9318.95 years to get there. We don't have the technology or spaceship that can carry people over that distance yet.

Variable Type of V2140 Cygni

The star is a eruptive Irregular variable type which means that its size changes over time. The Variable Type is usually named after the first star of that type to be spotted. V2140 Cygni brightness ranges from a magnitude of 5.836 to a magnitude of 5.745 over its variable period. The smaller the magnitude, the brighter the star. Its variable/pulsating period lasts for 0.1 days (variability).

Source of Information

The source of the information if it has a Hip I.D. is from Simbad, the Hipparcos data library based at the University at Strasbourg, France. Hipparcos was a E.S.A. satellite operation launched in 1989 for four years. The items in red are values that I've calculated so they could well be wrong. Information regarding Metallicity and/or Mass is from the E.U. Exoplanets. The information was obtained as of 12th Feb 2017.

V2140 Cygni Facts

Alternative Names

Traditional/Proper NameV2140 Cygni
Short NameV2140 Cyg
Hipparcos Library I.D.103312
Bonner DurchmusterungBD+46 3111
Henry Draper Designation199478

Visual Facts

Star Typesupergiant star
Visual / Apparent Magnitude5.68
Naked Eye VisibleYes - Magnitudes
Right Ascension (R.A.)20h 55m 49.81
Declination (Dec.)+47d25`03.6
Galactic Latitude1.42 degrees
Galactic Longitude87.51 degrees
1997 Distance from Earth0.35 Parallax (milliarcseconds)
 9318.95 Light Years
 2857.14 Parsecs
B-V Index0.40
Radial Velocity-15.00 ± 7.40 km/s
Iron Abundance-0.14 ± 9.99 Fe/H
Spectral TypeB8Ia
Colour(B) blue

Variable Star Details

Variable Star ClassEruptive
Variable Star TypeIrregular
Mean Variability Period in Days0.072
Variable Magnitude Range (Brighter - Dimmer)5.745 - 5.836

Estimated Facts

Luminosity (x the Sun)73,000.0000000
Calculated Effective Temperature6,398 Kelvin

Sources and Links

SIMBAD SourceLink

Related Stars

Add a Comment

Email: (Optional)