A space elevator is a proposed type of space-Earth transportation system. The bizzar concept of a space elevator was first published in 1895 by the Russian scientist Konstantin Tsiolkovsky. Space elevators a theoretical device that has a thin cable, called a 'tether', is anchored to the surface at the equator and counter-weighted end reaching into space. The counter-weight at the upper end keeps the center of mass well above geostationary orbit level. This produces enough upward centrifugal force from Earth's rotation to fully counter the downward gravity, keeping the cable upright and taut and straight. The cars, called 'climbers', move up and down it on on centrifugal force to go up and powerful superconductor motors to go down. They would not fly off the end in to outer space due to the