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Vega (Alpha Lyrae) - HD172167 - HIP91262 - HR7001

Vega (Alpha Lyrae) is a blue pulsating main sequence dwarf star that can be located in the constellation of Lyra. It is the 6th brightest star in the night sky. Alpha Lyrae is the Bayer Classification for the star. The Id of the star in the Yale Bright Star Catalogue is HR7001. HIP91262 is the reference name for the star in the Hipparcos Star Catalogue. The Id of the star in the Henry Draper catalogue is HD172167. Vega has alternative name(s), 3 Lyrae , alf_Lyr, 3 Lyr. In Arabic, it is known as Al-Waqi'.

Vega is a little more oval or egg shaped than other stars, caused by the rotation of the star. According to the Hipparcos datafile, it has a few stars orbitting it so they are influencing its shape. Its actually hotter at the poles than at the Equator unlike our own the Sun.

Vega, the Pole Star

Whilst Polaris is currently known as the Pole Star, it hasn`t always been the case and won`t always be the case. Thuban in Draco was the Pole Star in 3,000 B.C., roughly at the time of the building of the Pyramids. In 13,000 years time, Vega will become the Pole Star, the star closest to aligning with the North Pole. Vega won`t keep the title and Polaris will regain the title of Pole Star in another 13,000 years after that. Ref: N.A.S.A.

Location of Vega

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 Vega, the location is 18h 36m 56.19 and +38d46`58.8 .

Proper Motion of Vega

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 286.23 ± 000.28 towards the north and 200.94 ± 000.36 east if we saw them in the horizon.

Vega 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 24.0000000 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 Vega

Vega has a spectral type of A0Vvar. This means the star is a blue main sequence dwarf star. The star has a B-V Colour Index of 0 which means the star's temperature has been calculated using information from Morgans @ Uni.edu at being 9,531 Kelvin.

Vega has been calculated as 2.62 times bigger than the Sun.The Sun's radius is 695,800km, therefore the star's radius is an estimated 1,824,337.55.km.

Vega Apparent and Absolute Magnitudes

Vega has an apparent magnitude of 0.03 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 0.58 If you used the 2007 Parallax value, you would get an absolute magnitude of 0.60. 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 Vega

Using the original Hipparcos data that was released in 1997, the parallax to the star was given as 128.93 which gave the calculated distance to Vega as 25.30 light years away from Earth or 7.76 parsecs. It would take a spaceship travelling at the speed of light, 25.30 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 130.23 which put Vega at a distance of 25.05 light years or 7.68 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.

Variable Type of Vega

The star is a pulsating Delta Scuti 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. Vega brightness ranges from a magnitude of 0.000 to a magnitude of 0.000 over its variable period. The smaller the magnitude, the brighter the star.

Meteor Showers Radiating from near Vega

The Lyrids Meteor Shower radiants from a point near this star. The meteor shower runs typically between April 16-25 with a peak date of Apr. 22. The speed of a meteor in the shower is 49 Km/s. The amount of meteors predicted to be seen per hour (Zenith Hourly Rate) is 49.

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 Stellar Age, Metallicity or Mass is from the E.U. Exoplanets. The information was obtained as of 12th Feb 2017.

Vega Facts

Alternative Names

Traditional NameVega
Short Namealf Lyr, 3 Lyr
Arabic NameAl-Waqi'
English Meaning'The stooping' eagle
Bayer DesignationAlpha Lyrae
Alternative Name(s)3 Lyrae
Hipparcos Library I.D.91262
Yale Bright Star Catalogue (HR) Id7001
Bonner DurchmusterungBD+38 3238
Henry Draper Designation172167

Visual Facts

Star Typemain sequence dwarf star
Absolute Magnitude0.58 / 0.60
Apparent Magnitude0.03
Right Ascension (R.A.)18h 36m 56.19
Declination (Dec.)+38d46`58.8
1997 Distance from Earth128.93 Parallax (milliarcseconds)
 25.30 Light Years
 7.76 Parsecs
2007 Revised Distance from Earth130.23 Parallax (milliarcseconds)
 25.05 Light Years
 7.68 Parsecs
Proper Motion Dec.286.23 ± 0.28 milliarcseconds/year
Proper Motion RA.200.94 ± 0.36 milliarcseconds/year
B-V Index0.00
Spectral TypeA0Vvar
Brightest in Night Sky6th
Colour(A) blue

Variable Star Details

Variable Star ClassPulsating
Variable Star TypeDelta Scuti

Estimated Facts

Radius (x the Sun)2.62
Luminosity (x the Sun)24.0000000
Calculated Effective Temperature9,531 Kelvin

Sources and Links

SIMBAD SourceLink

Related Stars

Multi-Star System

The star has been identified as being a multi-star system, one in which there is at least one star in close orbit to another star or two or more stars orbiting a central point. The stars may be of equal mass, unequal mass where one star is stronger than the other or be in groups orbiting a central point which doesn't necessarily have to be a star. More information can be found on my dedicated multiple star systems page. The source of the info is Simbad. The file is dated 2000 so any differences between this and any other source will be down to the actual source from where the information came from.


Proper Motion mas/yr
H.D. IdB.D. IdStar CodeMagnitudeR.A.Dec.SpectrumColourYear
172167+38 3238.0A0.10000200.00000285.00000A0White
B9.500006.0000020.000001946
C11.00000-77.0000036.000001899
CD1897
E9.500007.00000-4.000001921

Location of Vega in Lyra


Vega (Alpha Lyrae) Location in Lyra

The map was generated using Night Vision, an awesome free application by Brian Simpson.


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Alex Vincent.Wednesday, 14th June 2017 5:10:15 PM
I have read ages ago that Vega is approaching us and the Sun is approaching Vega. How close will vega ending being to us then? It would be a very bright star if it got within a few lioght years of us. How much is it approaching us? Vega was the North Pole Star in 12,000 BC and will again obtain this position in 14,000 AD. It is the pole star every 26,000 years, but what of its proper motion? For example if its proper motion moves it in the sky by 30 minutes every 1,000 years {full Moon distance) then in say the year 78,000 AD, the star would have moved 39 degrees in the sky making no longer near the pole to be the North Pole Star again. This would apply to any stars, which become pole stars (south or north) in time and that others, which can't be pole stars now or in a few thousand years will be in 50,000 years time. Have you any comments on this please. Yours sincerely. Alex Vincent.