An areostationary orbit or areosynchronous equatorial orbit (AEO) is a circular areosynchronous orbit (ASO) in the

Martian Mars, the fourth planet from the Sun, has appeared as a setting in works of fiction since at least the mid-1600s. It became the most popular celestial object in fiction in the late 1800s as the Moon was evidently lifeless. At the time, the pred ...

equatorial plane The celestial equator is the great circle of the imaginary celestial sphere on the same plane as the equator of Earth. This plane of reference bases the equatorial coordinate system. In other words, the celestial equator is an abstract projectio ...

about above the surface, any point on which revolves about Mars in the same direction and with the same

period Period may refer to: Common uses * Era, a length or span of time * Full stop (or period), a punctuation mark Arts, entertainment, and media * Period (music), a concept in musical composition * Periodic sentence (or rhetorical period), a concept ...

as the Martian surface. Areostationary orbit is a concept similar to Earth's geostationary orbit (GEO). The prefix ''areo-'' derives from

Ares Ares (; grc, Ἄρης, ''Árēs'' ) is the Greek god of war and courage. He is one of the Twelve Olympians, and the son of Zeus and Hera. The Greeks were ambivalent towards him. He embodies the physical valor necessary for success in war b ...

, the ancient

Greek god The following is a list of gods, goddesses, and many other divine and semi-divine figures from ancient Greek mythology and ancient Greek religion. Immortals The Greeks created images of their deities for many purposes. A temple would house the ...

of war and counterpart to the

Roman god Roman mythology is the body of myths of ancient Rome as represented in the literature and visual arts of the Romans. One of a wide variety of genres of Roman folklore, ''Roman mythology'' may also refer to the modern study of these representat ...

Mars Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System, only being larger than Mercury (planet), Mercury. In the English language, Mars is named for the Mars (mythology), Roman god of war. Mars is a terr ...

, with whom the planet was identified. The

modern Greek Modern Greek (, , or , ''Kiní Neoellinikí Glóssa''), generally referred to by speakers simply as Greek (, ), refers collectively to the dialects of the Greek language spoken in the modern era, including the official standardized form of the ...

word for Mars is ''Άρης'' (Áris). To date, no

artificial satellite A satellite or artificial satellite is an object intentionally placed into orbit in outer space. Except for passive satellites, most satellites have an electricity generation system for equipment on board, such as solar panels or radioisoto ...

s have been placed in this orbit, but it is of interest to some scientists foreseeing a future telecommunications network for the exploration of

Formula

Orbital speed (how fast a satellite is moving through space) is calculated by multiplying the angular speed of the satellite by the orbital radius: :

R_ = \sqrt /math>
: G =

Gravitational constant The gravitational constant (also known as the universal gravitational constant, the Newtonian constant of gravitation, or the Cavendish gravitational constant), denoted by the capital letter , is an empirical physical constant involved in ...

: m₂ = Mass of the celestial body : T = rotational period of the body By this formula one can find the geostationary-analogous orbit of an object in relation to a given body, in this case,

(this type of orbit above is referred to as an areostationary orbit if it is above Mars). The mass of Mars being 6.4171×10²³ kg and the sidereal period 88,642 seconds. The synchronous orbit thus has a radius of 20,428 km (12693 mi) from the centre of mass of Mars, and therefore areostationary orbit can be defined as approximately 17,032 km above the surface of the Mars equator.

Stationkeeping

Any satellites in areostationary orbit will suffer from increased

orbital station keeping In astrodynamics, orbital station-keeping is keeping a spacecraft at a fixed distance from another spacecraft or celestial body. It requires a series of orbital maneuvers made with thruster burns to keep the active craft in the same orbit as its ...

costs, Silva and Romero's paper even includes a graph of acceleration, where a reaction force could be calculated using the mass of desired object: because the areostationary orbits lie between the orbits of the planet's two

natural satellite A natural satellite is, in the most common usage, an astronomical body that orbits a planet, dwarf planet, or small Solar System body (or sometimes another natural satellite). Natural satellites are often colloquially referred to as ''moons'' ...

s. Phobos has a

semi-major axis In geometry, the major axis of an ellipse is its longest diameter: a line segment that runs through the center and both foci, with ends at the two most widely separated points of the perimeter. The semi-major axis (major semiaxis) is the long ...

of 9,376 km, and

Deimos Deimos, a Greek word for ''dread'', may refer to: * Deimos (deity), one of the sons of Ares and Aphrodite in Greek mythology * Deimos (moon), the smaller and outermost of Mars' two natural satellites * Elecnor Deimos, a Spanish aerospace company * ...

has a semi-major axis of 23,463 km. The close proximity to Phobos' orbit in particular (the larger of the two moons) will cause unwanted

orbital resonance In celestial mechanics, orbital resonance occurs when orbiting bodies exert regular, periodic gravitational influence on each other, usually because their orbital periods are related by a ratio of small integers. Most commonly, this relationsh ...

effects that will gradually shift the orbit of areostationary satellites.

References

External links

Mars Network - Marsats
- NASA site devoted to future communications infrastructure for Mars exploration
Bandwidth available
from an areostationary satellite Mars orbits {{Mars-spacecraft-stub

Formula

Stationkeeping

See also

References

External links