Satellites may be launched into orbit which make a high angle of inclination with the equatorial plane, or a low angle of inclination. High inclination orbits, including fully "polar orbits", pass over nearly all latitudes of earth. Low inclination orbits pass over only tropical latitudes.

Environmental satellites in high inclination orbits are usually launched at relatively low altitudes so that their orbital period is short relative to the 24 hour period of earth's rotation. Thus, the earth rotates slowly underneath the satellite orbit, yielding a remote sensing system which views all parts of the globe in a 24 hour period.

Environmental satellites in low inclination orbits are launched in either of two altitude categories. Low altitude low inclination satellite orbits yield a remote sensing system which views all of the tropical latitudes around the earth several times each day. This is the design mode for the Tropical Rainfall Monitor Mission (TRMM) satellites under development. The second category is to launch a satellite with zero angle of inclination (that is, in the equatorial plane itself) and at such a high altitude that its orbital period is precisely one day. In this orbital mode, the satellite orbits in the equatorial plane at exactly the same rate as earth rotates. Such a satellite can observe exactly the same scene over and over (as frequently as every few minutes) providing a remote sensing system which can monitor very rapidly developing weather systems.