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[[Image:Vega in lyra.png|thumb|right|239px|Position and location of Vega in the Lyra constellation. Copyright © 2003 RJHall[http://en.wikipedia.org/wiki/User:RJHall]. Used with permission [http://en.wikipedia.org/wiki/File:Vega_in_lyra.png]]]

| image          =Vega in lyra.png

| designation    =Alpha Lyrae

| rightascension  =18h 36m 56.3364s

| declination    =+38^o 47′ 01.291″

| distance        =25.3 ly

| constellation  =[[Lyra]]

| type            =[[Star]]

| magnitude      =Apparent mag: 0.03<br/>Absolute Mag:0.58

| radvelocity    =−13.9 km/s

| propmotion      =RA: 201.03 mas/yr<br/>Dec.: 287.47 mas/yr

| parallax        =128.93 ± 0.55 mas

 

'''Vega''', also known as '''Alpha Lyrae''' is the fifth brightest star in the night sky, and is the brightest star of the constellation of [[Lyra]].  Vega is 25.3 light years away but still has an apparent magnitude of 0.03, allowing it be easily seen in all but the most light polluted skies<ref>http://simbad.u-strasbg.fr/simbad/sim-id?protocol=html&Ident=vega</ref>.

'''Vega''', also known as '''Alpha Lyrae''' is the fifth brightest star in the night sky, and is the brightest star of the constellation of [[Lyra]].  Vega is 25.3 light years away but still has an apparent magnitude of 0.03, allowing it be easily seen in all but the most light polluted skies<ref>http://simbad.u-strasbg.fr/simbad/sim-id?protocol=html&Ident=vega</ref>.

Vega is considered a very young star, and is estimated to be only some 350 million years old<ref>http://adsbit.harvard.edu/cgi-bin/nph-iarticle_query?1988A%26AS...76..411M</ref>.  Because it is far larger and hotter then our Sun, Vega will exhaust its core hydrogen only after another 650 million years or so, and leaving the main sequence turning into a red giant or a Cepheid variable.

Vega is considered a very young star, and is estimated to be only some 350 million years old<ref>http://adsbit.harvard.edu/cgi-bin/nph-iarticle_query?1988A%26AS...76..411M</ref>.  Because it is far larger and hotter then our Sun, Vega will exhaust its core hydrogen only after another 650 million years or so, and leaving the main sequence turning into a red giant or a Cepheid variable.

[[Image:Size Vega.png|thumb|right|250px|illustration of the size of Vega compared to the sun, note its elliptical shape due to its rotation speed.]]

[[Image:Size Vega.png|thumb|left|250px|illustration of the size of Vega compared to the sun, note its elliptical shape due to its rotation speed.]]

Vega rotates so fast that it only takes some 12.5 hours to complete one rotation, in comparison the Sun which takes 25.4 days to complete one rotation.    This rotation is so fast that observations suggest that the star is rotating at some 91 percent of the angular velocity needed to cause the star to physically fly apart.  Vega is thus 23 percent wider along its equator than at its poles, as well as some 2300K cooler<ref>http://www.noao.edu/outreach/press/pr06/pr0603.html</ref>.  Here on Earth, Vega is seen as pole on (looking directly at its pole).

Vega rotates so fast that it only takes some 12.5 hours to complete one rotation, in comparison the Sun which takes 25.4 days to complete one rotation.    This rotation is so fast that observations suggest that the star is rotating at some 91 percent of the angular velocity needed to cause the star to physically fly apart.  Vega is thus 23 percent wider along its equator than at its poles, as well as some 2300K cooler<ref>http://www.noao.edu/outreach/press/pr06/pr0603.html</ref>.  Here on Earth, Vega is seen as pole on (looking directly at its pole).