Universe Guide


W Lyrae - HD167740 - HIP89419

W Lyrae is a red pulsating star that can be located in the constellation of Lyra. The star can not be seen by the naked eye, you need a telescope to see it.

HIP89419 is the reference name for the star in the Hipparcos Star Catalogue. The Id of the star in the Henry Draper catalogue is HD167740.

W Lyrae has alternative name(s), W_Lyr.

Location of W Lyrae

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 W Lyrae, the location is 18h 14m 55.87 and +36d40`13.3 .

Physical Properties (Colour, Temperature, Radius) of W Lyrae

W Lyrae has a spectral type of M2e-M8e. This means the star is a red star. The star has a B-V Colour Index of 1.24 which means the star's temperature has been calculated using information from Morgans @ Uni.edu at being 4,494 Kelvin. The figure is derived at by using the formula from SDSS and has been known to produce widely incorrect figures.

W Lyrae Apparent and Absolute Magnitudes

W Lyrae has an apparent magnitude of 8.98 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 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 W Lyrae

Using the original Hipparcos data that was released in 1997, the parallax to the star was given as -2.10 which gave the calculated distance to W Lyrae as -1553.16 light years away from Earth or -476.19 parsecs. It would take a spaceship travelling at the speed of light, -1553.16 years to get there. We don't have the technology or spaceship that can carry people over that distance yet.

Variable Type of W Lyrae

The star is a pulsating Omicron Ceti 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. W Lyrae brightness ranges from a magnitude of 11.000 to a magnitude of 8.000 over its variable period. The smaller the magnitude, the brighter the star. Its variable/pulsating period lasts for 196.0 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.

W Lyrae Facts

Alternative Names

Traditional/Proper NameW Lyrae
Short NameW Lyr
Hipparcos Library I.D.89419
Bonner DurchmusterungBDD+36 3066
Henry Draper Designation167740

Visual Facts

Star Type star
Visual / Apparent Magnitude8.98
Naked Eye VisibleRequires a 7x50 Binoculars - Ref: Wiki
Right Ascension (R.A.)18h 14m 55.87
Declination (Dec.)+36d40`13.3
Galactic Latitude22.68 degrees
Galactic Longitude63.81 degrees
1997 Distance from Earth-2.10 Parallax (milliarcseconds)
 -1553.16 Light Years
 -476.19 Parsecs
B-V Index1.24
Radial Velocity-173.10 ± 1.00 km/s
Spectral TypeM2e-M8e
Colour(M) Red

Variable Star Details

Variable Star ClassPulsating
Variable Star TypeOmicron Ceti
Mean Variability Period in Days196.000
Variable Magnitude Range (Brighter - Dimmer)8.000 - 11.000

Estimated Facts

Calculated Effective Temperature4,494 Kelvin

Sources and Links

SIMBAD SourceLink

Related Stars

Add a Comment

Email: (Optional)