Universe Guide


V424 Lacertae, HD216946, HIP113288

V424 Lacertae is a orange to red pulsating very luminous supergiant star that can be located in the constellation of Lacerta. V424 Lacertae is the brightest star in Lacerta 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.

HIP113288 is the reference name for the star in the Hipparcos Star Catalogue. The Id of the star in the Henry Draper catalogue is HD216946.

V424 Lacertae has alternative name(s), V424 Lac.

Location of V424 Lacertae

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 V424 Lacertae, the location is 22h 56m 26.00 and +49d44`00.8 .

Proper Motion of V424 Lacertae

All stars like planets orbit round a central spot, in the case of planets, its the central star such as the Sun. In the case of a star, its the galactic centre. The constellations that we see today will be different than they were 50,000 years ago or 50,000 years from now. Proper Motion details the movements of these stars and are measured in milliarcseconds. The star is moving -3.43 ± 0.18 miliarcseconds/year towards the north and -0.48 ± 0.26 miliarcseconds/year east if we saw them in the horizon.

V424 Lacertae 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 20000.0000000 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 V424 Lacertae

V424 Lacertae has a spectral type of K5Ibvar. This means the star is a orange to red supergiant star. The star is 7534.00000000 Parsecs from the Galactic Centre or terms of Light Years is 24573.1463369600000000s. The star has a B-V Colour Index of 1.77 which means the star's temperature has been calculated using information from Morgans @ Uni.edu at being 3,167 Kelvin.

V424 Lacertae Radius has been calculated as being 179.33 times bigger than the Sun.The Sun's radius is 695,800km, therefore the star's radius is an estimated 124,775,439.50.km. However with the 2007 release of updated Hipparcos files, the radius is now calculated at being round 152.63. 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 -0.02 with an error value of 9.99 Fe/H with the Sun has a value of 1 to put it into context.

V424 Lacertae Apparent and Absolute Magnitudes

V424 Lacertae has an apparent magnitude of 4.99 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 -3.81 If you used the 2007 Parallax value, you would get an absolute magnitude of -3.46. 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 V424 Lacertae

Using the original Hipparcos data that was released in 1997, the parallax to the star was given as 1.74 which gave the calculated distance to V424 Lacertae as 1874.50 light years away from Earth or 574.71 parsecs. It would take a spaceship travelling at the speed of light, 1874.50 years to get there. We don't have the technology or spaceship that can carry people over that distance yet.

In 2007, Hipparcos data was revised with a new parallax of 2.04 which put V424 Lacertae at a distance of 1598.84 light years or 490.20 parsecs. It should not be taken as though the star is moving closer or further away from us. It is purely that the distance was recalculated.

The star's Galacto-Centric Distance is 7,534.00 Parsecs or 24,573.15 Light Years. The Galacto-Centric Distance is the distance from the star to the Centre of the Galaxy which is Sagittarius A*.

Variable Type of V424 Lacertae

The star is a pulsating Slow 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. V424 Lacertae brightness ranges from a magnitude of 5.105 to a magnitude of 5.035 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.

V424 Lacertae Facts

Alternative Names

Traditional/Proper NameV424 Lacertae
Short NameV424 Lac
Hipparcos Library I.D.113288
Bonner DurchmusterungBD+48 3887
Henry Draper Designation216946

Visual Facts

Star Typesupergiant star
Absolute Magnitude-3.81 / -3.46
Visual / Apparent Magnitude4.99
Naked Eye VisibleYes - Magnitudes
Right Ascension (R.A.)22h 56m 26.00
Declination (Dec.)+49d44`00.8
Galactic Latitude-9.00 degrees
Galactic Longitude104.59 degrees
1997 Distance from Earth1.74 Parallax (milliarcseconds)
 1874.50 Light Years
 574.71 Parsecs
2007 Revised Distance from Earth2.04 Parallax (milliarcseconds)
 1598.84 Light Years
 490.20 Parsecs
Galacto-Centric Distance24,573.15 Light Years / 7,534.00 Parsecs
Proper Motion Dec.-3.43 ± 0.18 milliarcseconds/year
Proper Motion RA.-0.48 ± 0.26 milliarcseconds/year
B-V Index1.77
Radial Velocity-9.50 ± 0.80 km/s
Iron Abundance-0.02 ± 9.99 Fe/H
Spectral TypeK5Ibvar
Colour(K) Orange to Red

Variable Star Details

Variable Star ClassPulsating
Variable Star TypeSlow Irregular
Mean Variability Period in Days0.064
Variable Magnitude Range (Brighter - Dimmer)5.035 - 5.105

Estimated Facts

Luminosity (x the Sun)20,000.0000000
Calculated Effective Temperature3,167 Kelvin

Sources and Links

SIMBAD SourceLink

Related Stars

Add a Comment

Email: (Optional)