Earth observation satellites usually follow the sun synchronousorbits. A sun synchronous orbit is a nearpolar orbit whose altitude is such that the satellite will alwayspass over a location at a given latitude at the same local solartime.
A satellite in lower Earth orbit is better to obtain high quality remote-sensing data. If placed in a sun-synchronous orbit (also named as polar orbit), the Earth will rotate beneath the orbiting satellite allow global coverage from a single satellite. Sun-synchronous satellites are generally placed at an altitude of about 600-850 km.
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