The Tundra orbit is a special type of Geosynchronous Orbit which is highly inclined from the Earth's equator. A Tundra orbit is also elliptical such that the satellite spends more time North of the equator than South of it.
At the present time, the only satellite company utilizing the Tundra Orbit is Sirius Satellite Radio. They have utilized the Tundra orbit to gain access to a market that normal geostationary satellites could not; the far North. Alaska is also an American state, and where satellite radio competitors using geostationary satellites could not completely take advantage of this market, Sirius Satellite Radio easily could. The only trade-off is that the satellite will eventually drop below the Earth's equator and therefore more than one satellite is required. Sirius currently has three satellites for this purpose in which at least one of them is North of the Earth's equator at any one time. They continuously hand off their responsibilities to their successors, much like passing the baton to the next racer.
The Tundra orbits of the the three Sirius Satellite Radio satellites. This image courtesy of Analytical Graphics Inc. (AGI).
The Tundra orbit ground track utilized by three Sirius Satellite Radio satellites. By comparison, a geostationary satellite ground track would be a single dot on this map. This image courtesy of Analytical Graphics Inc. (AGI).
Tundra Was Last Modified On May 23, 2010