Areosynchronous orbit
Encyclopedia
Areosynchronous orbits are class of synchronous orbit
s for artificial satellites around the planet Mars
. As with all synchronous orbits, an areosynchronous orbit has an orbital period
equal in length to Mars' sidereal day. A satellite in areosynchronous orbit does not necessarily maintain a fixed position in the sky as seen by an observer on the surface of Mars, however such a satellite will return to the same apparent position every Martian day.
An areosynchronous orbit that is equatorial (in the same plane as the equator
of Mars), circular, and prograde
(rotating about Mars' axis in the same direction as the planet's surface) is known as an areostationary orbit
(ASO). To an observer on the surface of Mars, the position of a satellite in ASO would appear to be fixed in a constant position in the sky. The ASO is analogous to a geostationary orbit
(GSO) about Earth.
Although no satellites currently occupy areosynchronous or areostationary orbits, some scientists foresee a future telecommunications network
for the exploration of Mars.
Synchronous orbit
A synchronous orbit is an orbit in which an orbiting body has a period equal to the average rotational period of the body being orbited , and in the same direction of rotation as that body.-Properties:...
s for artificial satellites around the planet Mars
Mars
Mars is the fourth planet from the Sun in the Solar System. The planet is named after the Roman god of war, Mars. It is often described as the "Red Planet", as the iron oxide prevalent on its surface gives it a reddish appearance...
. As with all synchronous orbits, an areosynchronous orbit has an orbital period
Orbital period
The orbital period is the time taken for a given object to make one complete orbit about another object.When mentioned without further qualification in astronomy this refers to the sidereal period of an astronomical object, which is calculated with respect to the stars.There are several kinds of...
equal in length to Mars' sidereal day. A satellite in areosynchronous orbit does not necessarily maintain a fixed position in the sky as seen by an observer on the surface of Mars, however such a satellite will return to the same apparent position every Martian day.
An areosynchronous orbit that is equatorial (in the same plane as the equator
Equator
An equator is the intersection of a sphere's surface with the plane perpendicular to the sphere's axis of rotation and containing the sphere's center of mass....
of Mars), circular, and prograde
Prograde
Prograde can refer to:*Prograde or direct motion, in astronomy, a type of motion of astronomical bodies* Prograde metamorphism, in geology, describes mineral changes in rocks under increasing pressure and/or temperature conditions...
(rotating about Mars' axis in the same direction as the planet's surface) is known as an areostationary orbit
Areostationary orbit
An areostationary orbit is a circular areosynchronous orbit in the Martian equatorial plane about above the surface, any point on which revolves about Mars in the same direction and with the same period as the Martian surface...
(ASO). To an observer on the surface of Mars, the position of a satellite in ASO would appear to be fixed in a constant position in the sky. The ASO is analogous to a geostationary orbit
Geostationary orbit
A geostationary orbit is a geosynchronous orbit directly above the Earth's equator , with a period equal to the Earth's rotational period and an orbital eccentricity of approximately zero. An object in a geostationary orbit appears motionless, at a fixed position in the sky, to ground observers...
(GSO) about Earth.
Although no satellites currently occupy areosynchronous or areostationary orbits, some scientists foresee a future telecommunications network
Telecommunications network
A telecommunications network is a collection of terminals, links and nodes which connect together to enable telecommunication between users of the terminals. Networks may use circuit switching or message switching. Each terminal in the network must have a unique address so messages or connections...
for the exploration of Mars.
External links
- Mars Network - Marsats - NASA site devoted to future communications infrastructure for Mars exploration