synchronous orbit

astronomy

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July 14, 2026

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A synchronous orbit is an orbit where a satellite's orbital period matches the rotation period of the celestial body it orbits. For Earth, this period is approximately 23 hours and 56 minutes.1

A special type of synchronous orbit is the geostationary orbit. This is a circular orbit located 35,785 km (22,236 miles) above Earth's Equator. Satellites in geostationary orbit appear stationary from Earth's surface, making them ideal for communications and weather satellites. The concept was proposed by Arthur C. Clarke in 1945.1

While synchronous orbits match the rotation period, geosynchronous orbits are any orbits with a period equal to Earth's rotation period. Communications satellites are often placed in these orbits so that ground-based dishes can maintain a consistent aim.12

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celestial mechanics
Examples of perturbations
, geostationary satellites, which orbit synchronously with Earth’s rotation) are destabilized by this deviation except at two longitudes. If the axial asymmetry is represented by a slightly elliptical Equator, the difference between the major and minor axis of the ellipse is about 64 metres, with the major axis located about…
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, geostationary satellites, which orbit synchronously with Earth’s rotation) are destabilized by this deviation except at two longitudes. If the axial asymmetry is represented by a slightly elliptical Equator, the difference between the major and minor axis of the ellipse is about 64 metres, with the major axis located about…
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Pluto
Pluto’s moons
…other words, Charon is in synchronous orbit around Pluto. As a result, Charon is visible from only one hemisphere of Pluto. It remains above the same location on Pluto’s surface, never rising or setting (just as do communications satellites in geostationary orbits over Earth; see spaceflight: Earth orbit). In addition,…
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…other words, Charon is in synchronous orbit around Pluto. As a result, Charon is visible from only one hemisphere of Pluto. It remains above the same location on Pluto’s surface, never rising or setting (just as do communications satellites in geostationary orbits over Earth; see spaceflight: Earth orbit). In addition,…
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