A polar orbit is an orbit that takes a satellite over the Earth's poles. In a polar orbit, the satellite travels over the North Pole and then over the South Pole on each orbit. This type of orbit is useful for satellites that need to observe the entire Earth's surface over time.

In a polar orbit, the satellite typically travels at a relatively low altitude, which allows for high-resolution images of the Earth's surface to be captured. The swath width, or the width of the area imaged by the satellite, is relatively narrow in a polar orbit, which means that the satellite can capture detailed images of specific areas of the Earth's surface.

Polar orbits are used by a variety of satellites, including Earth observation satellites that monitor weather patterns, natural disasters, and changes in the Earth's climate. Polar orbiting satellites are also used for scientific research, such as studying the Earth's atmosphere, oceans, and land cover.

Examples of polar orbiting satellites include the NOAA-NASA GOES series of weather satellites, which provide real-time weather data for the United States, and the European Space Agency's Sentinel-1 SAR satellite, which is used for monitoring changes in the Earth's land and sea ice. The Landsat series of Earth observation satellites also use a polar orbit to capture detailed images of the Earth's land surface over time.