Subsynchronous orbit

Kind of planetary orbit

A subsynchronous orbit is an orbit of a satellite that is nearer the planet than it would be if it were in synchronous orbit, i.e. the orbital period is less than the sidereal day of the planet.^[1]

Technical considerations

[edit ]

An Earth satellite that is in (a prograde) subsynchronous orbit will appear to drift eastward as seen from the Earth's surface.^[1]

Economic importance in commercial spaceflight

[edit ]

The Geosynchronous-belt subsynchronous orbital regime is regularly used in spaceflight. This orbit is typically used to house working communication satellites that have not yet been deactivated, and may be still be used again in geostationary service if the need arises.^[2]

References

[edit ]

^ ^a ^b Maral, Gérard; Michel Bousquet; Zhili Sun (2009). Satellite communications systems : systems, techniques and technology. Wiley. OCLC 701718866.
^ Kumar, Krishna (March 1993). "Geosynchronous satellites at sub-synchronous altitudes". Acta Astronautica. 29 (3): 149–151. Bibcode:1993AcAau..29..149K. doi:10.1016/0094-5765(93)90043-V.

v
t
e

Gravitational orbits

Types

General	Box Circular Elliptical / Highly elliptical Horseshoe Hyperbolic trajectory Inclined / Non-inclined Kepler Lagrange point Osculating Parabolic / Escape / Capture Parking Prograde / Retrograde Radial Synchronous semi sub Transfer orbit
Geocentric	Geosynchronous Geostationary Geostationary transfer Graveyard High Earth Low Earth Medium Earth Molniya Near-equatorial Orbit of the Moon Polar Sun-synchronous Transatmospheric Tundra Very low Earth
About other points	Mars Areocentric Areosynchronous Areostationary Lagrange points Distant retrograde Halo Lissajous Libration Lunar Sun Heliocentric Earth's orbit Mars cycler Heliosynchronous Other Lunar cycler

Parameters

Shape Size	e Eccentricity a Semi-major axis b Semi-minor axis Q, q Apsides
Orientation	i Inclination Ω Longitude of the ascending node ω Argument of periapsis π Longitude of the periapsis
Position	M Mean anomaly ν, θ, f True anomaly E Eccentric anomaly L Mean longitude l True longitude
Variation	T Orbital period n Mean motion v Orbital speed t₀ Epoch