NASA’s Kepler space telescope watches a lone star, Kepler-11

The star appears to blink in a pattern. It dims like clockwork as six "hands" of differing size orbit around it at different rates. Kepler-11 dims when its six orbiting planets cross between it and the Kepler spacecraft. Calculations of the orbits show that the planets are nested in orbits that lie in almost the same plane. Kepler-11, about 2,000 light years from Earth, is the most tightly packed planetary system yet discovered. All six of its planets have orbits smaller than Venus, and five of the six have orbits smaller than Mercury's. The only other star with more than one confirmed transiting planet is Kepler-9, which has three. See also: News Release of 2011 Feb 2 (NASA Finds Earth-size Planet Candidates in Habitable Zone, Six Planet System)