A space elevator, also referred to as a space bridge, star ladder, and orbital lift, is a proposed type of planet-to-space transportation system, often depicted in science fiction. The main component would be a cable anchored to the surface and extending into space. An Earth-based space elevator cannot be constructed with a tall tower supported from below due to its immense weight—instead, it would consist of a cable with one end attached to the surface near the equator and the other end attached to a counterweight in space beyond geostationary orbit. The competing forces of gravity, which is stronger at the lower end, and the upward centrifugal force, which is stronger at the upper end, would result in the cable being held up, under tension, and stationary over a single position on Earth. With the tether deployed, climbers (crawlers) could repeatedly climb up and down the tether by mechanical means, releasing their cargo to and from orbit. The design would permit vehicles to travel directly between a planetary surface, such as the Earth's, and orbit, without the use of large rockets.
Konstantin Tsiolkovsky
One concept for the space elevator has it tethered to a mobile seagoing platform.
A seagoing anchor station would also act as a deep-water seaport.
A conceptual drawing of a space elevator climber ascending through the clouds.
A geostationary orbit, also referred to as a geosynchronous equatorial orbit (GEO), is a circular geosynchronous orbit 35,786 km (22,236 mi) in altitude above Earth's equator, 42,164 km (26,199 mi) in radius from Earth's center, and following the direction of Earth's rotation.
A 5° × 6° view of a part of the geostationary belt, showing several geostationary satellites. Those with inclination 0° form a diagonal belt across the image; a few objects with small inclinations to the Equator are visible above this line. The satellites are pinpoint, while stars have created star trails due to Earth's rotation.
Syncom 2, the first geosynchronous satellite
A computer-generated image from 2005 showing the distribution of mostly space debris in geocentric orbit with two areas of concentration: geostationary orbit and low Earth orbit.