1. Other Objects in the Solar System

2. So far, we have studied: –Planets –Stars Which make up galaxies, constellations and asterisms The solar system also contains: –Moons –Asteroids –Meteors –Comets What Else is Out There?

3. Satellites Objects that revolve around planets are called satellites Satellites can be –Natural (not man-made) Example: moons –Artificial (man-made) Example: GPS and TV satellites

4. Moons A moon is a natural satellite The moons of other planets weren’t discovered until after the telescope was invented Earth’s moon has been visited six times between 1969 and 1972

5. Planet# of known moons Mercury0 Venus0 Earth1 Mars2 Jupiter39 Saturn30 Uranus20 Neptune8 Pluto1

6. Earth Jupiter (Europa & Io) Mars (Phobos & Deimos) Pluto (Charon)

7. Eclipses 1.Solar Eclipse -The Moon passes between the Earth and the Sun -This blocks our view of the Sun -Only occurs during New Moon 2.Lunar Eclipse -The Earth passes between the Moon and the Sun -The Moon is plunged into darkness as Earth’s shadow moves across it -Only occurs during Full Moon

8. Asteroids Asteroids are small, rocky objects that never formed into planets The ring of asteroids between the orbits of Mars and Jupiter is the asteroid belt The orbits of some asteroids cross the path of Earth and pose a potential collision hazard The largest asteroid, Ceres, is 1000 km in diameter

9. Eros Ceres

10. Asteroid Belt

11. Meteors, Meteoroids and Meteorites A meteoroid is a lump of rock or metal that is pulled through Earth’s atmosphere Friction between the meteoroid and the atmosphere causes the meteoroid to heat up Small meteoroids will vaporize Large meteoroids can burn up and generate enough light to become visible

12. Meteors, Meteoroids and Meteorites This fireball appears as a bright streak in the sky and is called a meteor –Sometimes called a shooting star Fragments of the meteor that are large enough or tough enough don’t burn up and strike Earth’s surface. A meteorite is a meteor remnant that survives to strike the Earth’s surface

13. MeteorMeteor Shower

14. The Barringer Meteorite Crater 4,000 ft 570 ft

15. Comets A comet is a chunk of frozen ice and dust that travels in a very long orbit around the Sun Occasionally, a comet gets bumped from its orbit and passes close to the Sun The frozen gases that make up the comet melt and evaporate as it approaches the Sun This forms a bright glowing tail that can be thousands of kilometers long and visible for several months

16. Halley’s Comet Comet Hyakutake