With all the talk about newly discovered planets orbiting stars other than our sun, it's easy to assume that planets are common as dirt in the universe. In fact, one odd characteristic of many stars makes planetary formation unlikely except in the strangest of cases. Our sun, which is of course loaded with planets, is unusual because it is alone. Most stars in the Milky way galaxy have other star orbiting around them.
Stars are enormously massive hydrogen bombs.
The presence of another star with its mass- generated gravitational pull makes planetary formation unlikely. A classic example of the problem is visible right now in even the smallest of telescopes. Look toward the southwest for the Y-shaped constellation Virgo, the maiden. A small telescope at high magnification will reveal that the star is really two stars, pale yellow beauties that look like twin headlights coming right at you from the inky depths of space. Since the two stars are of about equal mass, it's difficult to say which star is orbiting the other.