1. Satellites
D. Crowley, 2008

2. Satellites
To know how a satellite gets into space, and what they are used for

3. Gravity
Complete the gravity worksheet

4. Gravity
Force; equal; greater; attractive; mass; gravitational; closer

5. Satellite What is a satellite?
A satellite is any object that orbits another object
Satellites must travel at a given speed to stay in their orbits
There are two types of satellite: -
Natural satellites
Artificial satellites

6. Natural Satellites The moon is the natural satellite of the Earth
Gravitational forces between the moon and the Earth keep it in orbit
The moon is not a luminous object (it does not make its own light) but it does reflect light from the Sun
A satellite has to travel at the correct speed to stay in orbit at a particular distance from a planet. It takes the moon 28 days to make a complete orbit of the Earth (as it orbits, we see different amounts of the moon (different phases))

7. Artificial Satellites
An artificial satellite is an object made by and put into orbit by humans
Artificial satellites can have different type of orbits: -
Geostationary satellites
Polar orbit satellites
There are lots of artificial satellites in orbit around the Earth and they have many different uses, including: -
Communications, (TV broadcasting, telephone relays etc…)
Global Positioning System (GPS) & Galileo satellites for navigation
Weather forecasting
Scientific surveys of the Earth's surface & space (e.g. Hubble)
Map making
Spying

8. Geostationary Satellites
Stay above the same point on Earth
Speed of orbit matches the Earth’s rotation, so orbit time is 24 hours
Used for communications, satellite TV, weather forecasting, intelligence, global positioning etc…

9. Polar Orbit Satellites
Low orbit around the Earth, passing over North and South poles
Earth rotates underneath them as they orbit
Used for large-scale mapping and global weather monitoring

10. Satellites

11. Space Travel How difficult is it to get into space?
What about getting to the moon?
How about other planets… or solar systems?!
Space travel is never routine - it is extremely dangerous (space is very hostile) and if a rocket malfunctions you don’t usually walk away…

12. Going To The Moon
Complete the going to the moon worksheet

13. Going To The Moon Lots of Earth’s gravity
Moon’s gravity affects lander
Moon’ gravity still affects space craft
Gravity of Earth still strong
Moon’s gravity weakens, Earth’s increases
Moon’s gravity affects lander
Moon’s gravity tries to pull orbiter down
Earth’s gravity very strong