Vega Older Than Previously Thought, Could Harbor Life

vega-lyra-age-fast-spinning

Vega in the night sky. Credit: Martin S. Mitchell

Vega is situated in the constellation Lyra, 25 light-years away from Earth, and it is the fifth brightest star in the sky. In 1983, astronomers discovered dust orbiting Vega, suggesting that it had a solar system. Vega was thought to be only a couple of hundred million years old, probably too young for any planets to have spawned life. However, new estimates show that Vega is significantly older than previously thought.

The scientists will publish their findings in The Astrophysical Journal Letters, but a preprint is available through arXiv. Astronomers have learned that the star spins fast, about once every 17 hours, which stirs up the star’s interior, and forces the surface composition to match the overall composition of the star. This means that scientists had been overestimating the star’s abundance of heavy metals, meaning that they overestimated its mass and underestimating its age. Massive stars evolve more slowly.

The astronomers studied Vega using the CHARA interferometer, an array of telescopes in California, and modeled the observations by using new computations of how fast-spinning stars age.

Vega is 2.15 times as massive as the sun, but between 625 million and 850 million years old. Suitable planets could have formed and sufficient time has elapsed for the development of primitive life.

[via ScienceNOW]

4 Comments on "Vega Older Than Previously Thought, Could Harbor Life"

  1. Vega is relatively close to earth. If that is the case, how can a star that is 4.5 billion years old ( Sol ) be in proximity of a star that is very young in star years 600-800 million years old? What spawned Vega’s birth and if it was a super nova or some sizable event, how come it didn’t effect the earth?

    • The stars all move around the galaxy independent of each other. The orbits, velocities, and inclinations all independent of each other. Hundreds of millions of years ago Vega and our sun could have been thousands of light years apart or even o n other sides of the galaxy. Were only neighbors for a very small point of time. Vega was probably born in a stellar nebula.

  2. Don’t massive stars actually evolve and therefore age much quicker, not more slowly, as is claimed in this article. Isn’t that why with a reduced mass Vega is actually older than they previously estimated?

    • Agreed. I was surprised by the article stating that massive stars evolve slowly. 2.135 times the size of Sol is not massive in my opinion, nor do I really think it’s the Author’s either. Astrophysicists agree that massive stars live fast and die young. They burn through their hydrogen really fast when they are stars like VY Canis Majoris (30 solar masses). I have read that this behavior usually begins in stars around 5+ solar masses.

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