1. Other objects in the Solar System

2. S1-4-08b Differentiate between the major components of the universe. KEY WORDS MoonAsteroidTrojan MeteoroidMeteoriteMeteor Comet

3. Moons

4. Moon: Large natural object (rock/metals) that revolves around a planet – also called a satellite. Probes (robot explorers) have investigated moons of Mars, Jupiter and Saturn The Roman goddess of the moon was Luna Planet (2006)Known moons Mercury0 Venus0 Earth1 Mars2 Jupiter63 Saturn60 Uranus27 Neptune13 Pluto3 (Oct 2008) 172 known moons in our Solar System

5. Io - only moon known to have active volcanoes Europa – contains more ice and water than Earth and may contain life.

6. Humans have visited the moon’s surface six times between 1969 and 1972. 1 st - Soviet Luna 2 (1959) 2 nd brightest object in sky No atmosphere ¼ diameter of Earth The gravitational pull of the moon on our ocean is what causes the tide to rise and fall

7. Asteroids

8. Asteroid: Chunk of rock/metal that orbits the Sun but too small to be planets – minor planets. Asteroid that cross path with Earth called Trojans The fear is that a Trojan passes close enough to get pulled in by Earth’s gravity and collide Asteroid belt in large gap from Mars – Jupiter Largest is only 1000 Km in diameter Asteroids are rich in minerals – future mining

9. Meteoroids

10. Meteoroid: lump of rock that is trapped by Earth’s gravity and pulled into the atmosphere. The only difference between meteoroid and asteroid is that a meteoroid is random, an asteroid orbits the Sun Falling meteoroids bump into air molecules heating up (friction) until the air glows – and the meteoroid burns up and breaks apart. Meteoroid that completely burns up - meteor producing a streak of light - shooting star

11. Meteorite: fragment of a meteoroid that doesn’t burn up and strikes the Earth (space rock). Large meteorites make craters Westhawk Lake is a crater Meteorite impact crater in Arizona

12. Comets

13. Some have regular periods of revolution around the Sun Comet: chuck of ice/dust that orbits the Sun. Made of the head (coma) and the tail Tail: passing by Sun heats trailing gas and debris then blown out by solar wind - millions of km long Halley’s comet: last seen in 1986 it has a period of 76 years

15. CAN YOU ANSWER THESE QUESTIONS? S1-4-08b: What other objects make up our solar system? KEY WORDS MoonAsteroidTrojan MeteoroidMeteoriteMeteor Comet