Universe Guide
AliensAliensConstellationsTelevision and Films ListFact ListGames ListWarcraftSearchTwitterFacebook


79 Pegasi, HD223461, HIP117500, HR9025

79 Pegasi is a blue star that can be located in the constellation of Pegasus. 79 Pegasi is the brightest star in Pegasus 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.

The Id of the star in the Yale Bright Star Catalogue is HR9025. HIP117500 is the reference name for the star in the Hipparcos Star Catalogue. The Id of the star in the Henry Draper catalogue is HD223461.

Location of 79 Pegasi

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 79 Pegasi, the location is 23h 49m 39.35 and +28d 50` 32.4 .

Proper Motion of 79 Pegasi

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 24.61 ± 0.26 miliarcseconds/year towards the north and 63.21 ± 0.38 miliarcseconds/year east if we saw them in the horizon. The Radial Velocity, that is the speed at which the star is moving away/towards us is -4.30000 km/s with an error of about 2.90 km/s .

Physical Properties (Colour, Temperature, Radius) of 79 Pegasi

79 Pegasi has a spectral type of A2m. This means the star is a blue star. The star is 7422.00000000 Parsecs from the Galactic Centre or terms of Light Years is 24207.8433916800000000s. The star has a B-V Colour Index of 0.18 which means the star's temperature has been calculated using information from Morgans @ Uni.edu at being 7,564 Kelvin.

79 Pegasi Radius has been calculated as being 2.87 times bigger than the Sun.The Sun's radius is 695,800km, therefore the star's radius is an estimated 1,994,670.40.km. However with the 2007 release of updated Hipparcos files, the radius is now calculated at being round 3.10. The figure is derived at by using the formula from SDSS and has been known to produce widely incorrect figures.

79 Pegasi Apparent and Absolute Magnitudes

79 Pegasi has an apparent magnitude of 5.95 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 1.39 If you used the 2007 Parallax value, you would get an absolute magnitude of 1.22. 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 79 Pegasi

Using the original Hipparcos data that was released in 1997, the parallax to the star was given as 12.22 which gave the calculated distance to 79 Pegasi as 266.91 light years away from Earth or 81.83 parsecs. It would take a spaceship travelling at the speed of light, 266.91 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 11.32 which put 79 Pegasi at a distance of 288.13 light years or 88.34 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 7,422.00 Parsecs or 24,207.84 Light Years. The Galacto-Centric Distance is the distance from the star to the Centre of the Galaxy which is Sagittarius A*.

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.

79 Pegasi Facts

Alternative Names

Traditional/Proper Name79 Pegasi
Flamsteed Name79 Pegasi
Flamsteed Short Name79 Peg
Hipparcos Library I.D.117500
Yale Bright Star Catalogue (HR) Id9025
Bonner DurchmusterungBD+28 4649
Henry Draper Designation223461

Visual Facts

Star Type star
Absolute Magnitude1.39 / 1.22
Visual / Apparent Magnitude5.95
Naked Eye VisibleYes - Magnitudes
Right Ascension (R.A.)23h 49m 39.35
Declination (Dec.)+28d 50` 32.4
Galactic Latitude-32.10 degrees
Galactic Longitude106.95 degrees
1997 Distance from Earth12.22 Parallax (milliarcseconds)
 266.91 Light Years
 81.83 Parsecs
2007 Revised Distance from Earth11.32 Parallax (milliarcseconds)
 288.13 Light Years
 88.34 Parsecs
Galacto-Centric Distance24,207.84 Light Years / 7,422.00 Parsecs
Proper Motion Dec.24.61 ± 0.26 milliarcseconds/year
Proper Motion RA.63.21 ± 0.38 milliarcseconds/year
B-V Index0.18
Radial Velocity-4.30 ± 2.90 km/s
Spectral TypeA2m
Colour(A) blue

Estimated Facts

Calculated Effective Temperature7,564 Kelvin

Sources and Links

SIMBAD SourceLink

Related Stars

Add a Comment

Email: (Optional)