Polar orbiting satellites are much closer to the Earth's surface than geostationary satellites, and can therefore give higher resolution images of smaller areas.

Polar satellites rotate around the Earth from pole to pole. Since the Earth is also rotating beneath the satellite, the satellite can see the entire Earth, one north-south swath at a time. If the satellite passes over any given point of the Earth's surface at the same local solar time, it is said to be in a "sun-synchronous" orbit.

Typically, polar orbiting satellites are located about 1,000 km (600 miles) above the ground, and each orbit takes about 100 minutes. On a dark night far from city lights, you can usually spot a few of these satellites moving through the sky. They look like tiny stars, but they are moving. For example, Nimbus-7 is a satellite jointly operated by NASA and NOAA that has been in orbit since 1978. It crosses the equator at noon and midnight local time and is in orbit at 955 km (593 miles). Nimbus-7 is able to measure stratospheric aerosols, radiation, temperatures, and humidity.