Geology of solar terrestrial planets Earth, and Mars) have substantial atmospheres; all have impact craters and tectonic surface features such as rift valleys and volcanoes. The term "inner planet" should not be confused with "inferior planet", which refers to any planet that is closer to the Sun than the observer's planet is, but usually refers to Mercury and Venus. The Solar System is believed to have formed according to the nebular hypothesis, first proposed in 1755 by Immanuel Kant and independently formulated by Pierre-Simon Laplace. This theory holds that 4.6 billion years ago the Solar System formed from the gravitational collapse of a giant molecular
Mr. Martian Mr. Martian Mr. Martian (AKA: CH'kk Kk'xx – Chuck Cox) is a fictional character in Big Bang Comics, who first appeared in "Big Bang" #21, but didn't receive his own story until "World Class Comics" #1. CH'kk Kk'xx is a Martian originally sent to investigate planet Earth and see that the Nuclear Age went without disaster. CH'kks' spaceship crashed outside of Roswell after being shot down by the American Air Force, mistaking it for a Communist attack. CH'kk went underground as Chuck Cox, and soon came to like the Earth, and instead decided to defend it from his own planet.