Planets, asteroids, and vast clouds of dust encircle the star Vega in this artist's concept. Recent research shows that two vast rings of debris encircle Vega. One ring resembles the asteroid belt in our own solar system, while the other, which is farther from the star, resembles the Kuiper Belt, a zone of icy objects. Vega is in good view on summer nights as the brightest point of the Summer Triangle. [David Hardy]
The second-brightest star in the northern half of the sky is in great view as we head toward summer. Vega is well up in the east as darkness falls and climbs high overhead later on.
Vega is a bit like a scaled-up version of the Sun — it’s more than twice the Sun’s diameter and mass. And recent research shows that it’s encircled by scaled-up versions of the belts of comets and asteroids that surround the Sun — suggesting that it could have a scaled-up planetary system as well.
Two large space telescopes mapped the debris around Vega in detail — bits of dust, rock, and ice that glow at infrared wavelengths.
By studying the observations, astronomers determined that Vega has a ring of dust and rock that resembles the asteroid belt in our own solar system. They also found that there’s a much larger ring of cold material that’s much farther from Vega. That ring resembles the Kuiper Belt — a broad band of icy comets that’s beyond the orbit of Neptune, the Sun’s most distant planet.
The Vega system is about four times wider than the solar system. But if you scaled up the solar system, those belts of debris would look almost identical.
In the solar system, there are four planets between the Sun and the asteroid belt, and four more between the asteroid belt and the Kuiper Belt. No one has yet found any planets orbiting Vega. But the new observations suggest that planets could be orbiting the star — clearing out wide zones between Vega’s “dusty” belts.
Script by Damond Benningfield, Copyright 2013
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