Satellites
Learning Goals
I WILL UNDERSTAND THE IMPORTANCE AND ROLES OF SATELLITES.
I WILL UNDERSTAND CANADA’S ROLE IN THE DEVELOPMENT OF SATELLITES.
Satellites
1 natural satellite – the moon
1000s of artificial satellites More than 40 countries have put more than 3000 satellites into orbit!
Orbit outside the Earth’s atmosphere at altitudes of 200km to 35 000 km!
Human occupied: Space shuttle
International Space Station
is 350 km from Earth and takes 90 min to orbit Earth
Brief history
Sputnik I – USSR in 1957
Explorer I – USA in 1958
Alouette I – Canada in 1962
Early bird – first communication satellite in 1965
How Satellites Work
Canada’s Role
World leader in the last 50 years in developing satellite technology
Have built very powerful telecommunication and Earth observation satellites
Staying in Orbit
The force of the Earth’s gravity constantly pulls the satellite towards Earth
The forward motion of the satellite and the curvature of Earth prevents it from falling into the atmosphere
Low Earth Orbit Satellites
Altitudes up to 2000 km
Orbit is close to the Earth, only just above the atmosphere.
With a good camera you can see the headlines on a newspaper!
Human occupied & Earth observation
Medium Earth Orbit Satellites
Altitudes up to 35 000 km
GPS satellites
24 satellites and ground stations
Making two complete orbits in less than 24 hrs
Travelling at 11 000 km/h
Use three satellites to triangulate a location
Altitudes up to 35 000 km
GPS satellites
24 satellites and ground stations
Making two complete orbits in less than 24 hrs
Travelling at 11 000 km/h
Use three satellites to triangulate a location
Geostationary Orbit Satellites
path is directly over equator with a period equal to the period of the Earth’s rotation.
Appear motionless in the sky
At the right distance the satellite will take 24 hours to orbit the Earth. Because the Earth is also spinning once each 24 hours the satellite stays above the same place on the Earth all the time.
Used to broadcast TV and radio
Space Debris
According to the U.S. Space Command (USSC), there are more than 8,000 objects larger than a softball now circling the globe.
Of these, over 2000 are satellites (working and not).
Learning Goals Revisited
I WILL UNDERSTAND THE IMPORTANCE AND ROLES OF SATELLITES.
I WILL UNDERSTAND CANADA’S ROLE IN THE DEVELOPMENT OF SATELLITES.
Please Complete
Pg. 351 #2 and 9
Read Mysteries Beyond the Planets (Pg. 353) and summarize the article in one paragraph.