Vega

Vega is a bright blue star 25 light years away. Vega is the brightest star in the Summer Triangle, a group of stars easily visible summer evenings in the northern hemisphere. It's companions are Deneb and Altair. Vega is also known as Alpha Lyrae.

"14,000 years ago, Vega, not Polaris, was the north star. Vega is the fifth brightest star in the night sky, and has a diameter almost three times that of our Sun." (NASA) It is 60 times brighter than the Sun, and is projected to have a lifetime of about 350 million years, or 1/13 the lifetiime of the Sun.

Images made by the Spitzer Space Telescope give details about the large dust cloud surrounding Vega. This massive amount of debris is thought to be the result of a collision of perhaps Pluto sized objects. This dust is being blown away by the intense light of the star, so the collision is likely to have occurred within the last million years. The massive dust disk extends to at least 815 astronomical units, or about 20 times the size of our solar system.

Sources

• http://antwrp.gsfc.nasa.gov/apod/ap980823.html
• http://www.jpl.nasa.gov/news/news.cfm?release=2005-007
• http://www.spitzer.caltech.edu.