Altair

Altair is known to stargazers in the Northern Hemisphere as part of the “Dave Triangle” (Deneb, Altair and Vega) of bright stars visible during summer.  In fact, it’s one of the brightest objects in the night sky, because it’s only 16.8 light years away -- and because it’s an A7V star, big and white and hot.  Not surprisingly, it’s also young, at under a billion years old.  So it’s not a great prospect for habitable planets, because anything in the life zone won’t have had time to develop much of an ecosystem.  If it does have anything usable, it will be located at least three AU from the star. 

Oh, well, there are several much better possibilities located between 17 and 20 light years out, as we shall see.