Statite
Encyclopedia
A statite is a hypothetical type of artificial satellite
that employs a solar sail
to continuously modify its orbit
in ways that gravity alone would not allow. Typically, a statite would use the solar sail to "hover" in a location that would not otherwise be available as a stable geosynchronous orbit
. Statites have been proposed that would remain in fixed locations high over Earth
's poles, using reflected sunlight
to counteract the gravity pulling them down. Statites might also employ their sails to change the shape or velocity of more conventional orbits, depending upon the purpose of the particular statite.
The concept of the statite was invented by Robert L. Forward
. No statites have been deployed to date, as solar sail technology is still in its infancy.
Satellite
In the context of spaceflight, a satellite is an object which has been placed into orbit by human endeavour. Such objects are sometimes called artificial satellites to distinguish them from natural satellites such as the Moon....
that employs a solar sail
Solar sail
Solar sails are a form of spacecraft propulsion using the radiation pressure of light from a star or laser to push enormous ultra-thin mirrors to high speeds....
to continuously modify its orbit
Orbit
In physics, an orbit is the gravitationally curved path of an object around a point in space, for example the orbit of a planet around the center of a star system, such as the Solar System...
in ways that gravity alone would not allow. Typically, a statite would use the solar sail to "hover" in a location that would not otherwise be available as a stable geosynchronous orbit
Geosynchronous orbit
A geosynchronous orbit is an orbit around the Earth with an orbital period that matches the Earth's sidereal rotation period...
. Statites have been proposed that would remain in fixed locations high over Earth
Earth
Earth is the third planet from the Sun, and the densest and fifth-largest of the eight planets in the Solar System. It is also the largest of the Solar System's four terrestrial planets...
's poles, using reflected sunlight
Sunlight
Sunlight, in the broad sense, is the total frequency spectrum of electromagnetic radiation given off by the Sun. On Earth, sunlight is filtered through the Earth's atmosphere, and solar radiation is obvious as daylight when the Sun is above the horizon.When the direct solar radiation is not blocked...
to counteract the gravity pulling them down. Statites might also employ their sails to change the shape or velocity of more conventional orbits, depending upon the purpose of the particular statite.
The concept of the statite was invented by Robert L. Forward
Robert Forward
Robert Lull Forward — known as Robert L. Forward — was an American physicist and science fiction writer...
. No statites have been deployed to date, as solar sail technology is still in its infancy.