Summer has long since passed us by, but its signature star pattern remains in good view. The Summer Triangle is high in the west at nightfall. The brilliant star Vega marks its lower right point. Deneb is high above Vega, with Altair farther to the left of Vega. The space between Vega and Deneb is littered with planets. In fact, more than half of the confirmed planets in other star systems have been found in that small patch of sky. That’s not because there really are more planets there. Instead, that’s where the search for exoplanets has been centered. Most of those discoveries were made by Kepler, a small space telescope that’s been looking for planets for about six years. For about half of that time, it was staring at a single patch of sky — between Vega and Deneb. Kepler monitored the brightness of about 150,000 stars in that region. It was looking for planets to pass in front of those stars, briefly dimming their light. That technique has revealed more than a thousand confirmed pl
