Pluto & other objects in the outer solar system

1. Pluto & other objects in the outer solar system

2. Pluto and most objects in the outer solar system are made of ice and rock • The materials in a space body depend on where it is formed • Bodies that formed near the center of the solar system are hotter and are made mostly of rock and metal • Bodies that formed far from the center are colder and are made mostly of ice with some rock and a little metal

3. Asteroids and comets orbit the Sun • Small, solid, rocky bodies that orbit close to the Sun are called asteroids. • Range in size from almost 1000 km in diameter to a kilometer or less • Surface of asteroids • Covered with craters, broken rock, and dust • Sometimes hit by smaller objects Asteroid Ceres

4. Asteroids and comets orbit the Sun • A body that produces a coma of gas and dust is a comet. • Comets formed far from the Sun, so they are made of different ices, as well as rock and some metal.

5. Meteors & Meteorites Meteors Meteorite A small object from outer space that passes through Earth’s atmosphere and reaches the surface. Outside of this object is usually smooth from melting, but the inside may still be frozen. • A brief streak of light produced by a small particle entering Earth’s atmosphere. Meteor Shower

6. Pluto • Pluto has 4 moons • Diameter: 18% of Earth’s diameter • Mass: 0.2% of Earth’s mass • Average distance from the Sun: 40 AU • Orbits in 248 Earth years • Rotates in 6 Earth days