SATELLITES

Artificial Satellites Natural satellites A celestial object travels around a planet or dwarf planet (ex a moon) Artificial Satellites Man-made satellites circling at different altitudes and orbits Forecast weather Monitor agriculture Telecommunications/navigation Military activities Explore the universe

In 1957, Soviet union launched the 1st satellite, Sputnik 1 into space

In 1962, Canada launched, Alouette 1 into space

Canada’s Contribution Canada’s MOST "My Own Space Telescope" Space Telescope probes stars outside the solar system measures changes in star light emissions.

Canada’s RADARSAT Satellite (Polar orbit) monitors a variety of natural & human-made events ex. charts icebergs in Canada’s far Artic ocean

Canada’s Communication satellite Nimiq 4 Sends TV broadcast signals across most of North America

STAYING IN ORBIT Earth’s gravity pulls the satellites toward earth BUT This is balanced by the forward motion of the satellite & the curvature of the earth

REASONS FOR LAUNCHING SATELLITES Measuring characteristics of planets around distant stars. Searching potentially dangerous asteroids Determine the positions of given objects on the surface of the earth Track weather

Types of Orbits Low earth orbit satellites Medium Earth satellites Altitude of up to 2000km Provides global coverage. Monitor around the world (ice caps) Polar Orbit Travels at an altitude of 200 – 900 km in a path over both the North & South pole Medium Earth satellites Altitude of up to 35 000km. Global Positioning System (GPS) Satellites used to find positions of objects on the earth Geostationary satellites Orbital path directly above Earth’s equator. Altitudes of 35790 km and appear motionless in the sky Useful in communications, weather tracking …

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