Satellites provide information for weather forecasts and navigation, monitor conditions Earth and transmit communication signals.

Weather Satellites:

Weather Satellites monitor climate patterns on Earth. They provide advance warnings of dangerous weather systems such as cyclones. Some weather satellites are in geostationary orbits which means they remain positioned over the same spot on Earth.

Communication Satellites:

Communication Satellites are also in geostationary orbits. These satellites receive television, data and telephone signals from one spot on Earth and re-transmit them to other places on Earth.

Navigation Satellites:

Navigation Satellites can locate people's position and speed of movement on Earth. This system of navigation is called the Global Positioning System (GPS). GPS satellites continually transmit to receivers on Earth. Receivers may be on ships or planes in motor vehicles or carried by people. A receiver uses the signals from four satellites to calculate position, speed and exact time. These signals can also be tracked by search and rescue teams.

Scientific and Observation Satellites:

Scientific and observation satellites monitor conditions on Earth. Observation satellites fly at a lower orbit and take high-resolution images of the Earth's surface. These are used for mapping and to record ice movements, crop problems and rainforest logging. Scientific satellites monitor volcanoes and changes in Earth's atmosphere.