Planet Bonanza: The Number of Known Earth-Sized Worlds Just Topped 100

Astronomers working with the Kepler space telescope just made a series of announcements that are fairly staggering: They have confirmed an additional 700+ exoplanets orbiting 300 other stars. Ninety-five percent of these planets are smaller than Neptune. One hundred or so are roughly the size of Earth(!!!). Four of these new planets are in their stars' habitable zone. Like our solar system, these planets orbit in roughly the same plane. Yegads. OK, let's go over these point by point. First, Kepl...