Vega

The fifth brightest star in the sky, Vega is an unmistakable sight on northern summer nights.  It forms the northern apex of the northern “Summer Triangle.  The other two stars of this unofficial constellation are Deneb and Altair.  Officially, however  Vega is the alpha star in Lyra, which represents the harp of the great mystical musician Orphenus.

Vega is a classic class A (A0) white dwarf star like our own Sun.  It is about 1/10th of the Sun’s age and already halfway through its hydrogen fuel supply.  Vega appears to rotate slowly, but that is only because its axis points almost directly at Earth.  In reality, it spins much more rapidly than our Sun … as it completes its rotation in 12 hours.  For comparison, it takes our Sun 26 days to complete a rotation.  The fast rotation of Vega makes it bulge out significantly around its equator.  It is also surrounded by debris disc of gas and dust left over from its formation.  The debris may be in the process of forming planets.

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Vega Overview:

  • Constellation Lyra (Lira)
  • Alpha (α) 18h37m, +38°37′
  • Type Main sequence star
  • Magnitude 0.03
  • Luminosity  36 Suns
  • Spectral Type A0V
  • Distance 25 light years

Lyra Constellation … The Lyre

Lyra is a small but prominent constellation thanks to Vega.  Lyra, represents a lyre, the ancient musical instrument played by Orphenus during his journey into the underworld of the Greek mythological afterlife.  It was Hermen, son of Zeus and Maia (of the Pleiades) who invented the lyre.  He made it by tying seven strings, made from cow gut, across a tortoise shell.   The seven strings coincidentally match the Seven Sisters of Greek mythology found in the Pleiades.

Astronomy 101