In the Courts of the Crimson Kings In the Courts of the Crimson Kings In the Courts of the Crimson Kings is a 2008 alternate history science fiction novel by American writer S. M. Stirling. The story takes place on the planet Mars in an alternate solar system where probes from the United States of America and the Soviet Union find intelligent life and civilizations on both Venus and Mars. The book is heavily influenced by the works of writers such as Edgar Rice Burroughs, Ray Bradbury, and Leigh Brackett, among others. It is a sequel to "The Sky People", which is set on Venus. Stirling later
Planet the Drake equation, which estimates the number of intelligent, communicating civilizations that exist in the Milky Way. There are exoplanets that are much closer to their parent star than any planet in the Solar System is to the Sun, and there are also exoplanets that are much farther from their star. Mercury, the closest planet to the Sun at 0.4 AU, takes 88 days for an orbit, but the shortest known orbits for exoplanets take only a few hours, e.g. Kepler-70b. The Kepler-11 system has five of its planets in shorter orbits than Mercury's, all of them much more massive