Planets, orbits, and moons, oh my! Outer Space! Planets, orbits, and moons, oh my!

Astronomical Unit Definition: (AU) the average distance between the Earth and the sun; approximately 150 million km

like an atom, most of space is…well…empty space! The distance between things in space is HUGE! We measure distance in space by light-years. This is a measure of DISTANCE, not time. It is how far something would travel if it traveled at the speed of light for one year. Speed of light: 299,792,458 m/s Light year: 9,460,528,400,000,000 meters (9.4 quadrillion meters) That’s 5,878,499,810,000 miles! (5.8 trillion miles!)

Terrestrial planet Definition: one of the highly dense planets nearest to the sun (Mercury, Venus, Earth, and Mars)

THINGS IN SPACE ARE BIG! http://www.youtube.com/watch?v=7T1LO6nOUdw

Gas giant Definition: a planet that has a deep, massive atmosphere (such as Jupiter, Saturn, Uranus, or Neptune)

Satellite Definition: a natural or artificial body that revolves around a planet

Celestial body = astronomical object Naturally occurring things or structures that we find in space Let’s look at some! http://www.youtube.com/watch?v=FGYTqOxu7u0

Researching celestial bodies You must read the textbook (somewhere in chapter 21) to find out information about your assigned planets. You must READ the entire section for each of your planets! Mercury, Venus, Earth Mars, Jupiter Saturn, Uranus, Neptune Pluto, Luna (Earth’s Moon)

Why is Earth a special planet? It has oxygen in its atmosphere It has liquid water on it It’s the right temperature

Eclipse Definition: an event in which the shadow of one celestial body falls on another

What makes Earth special?? Inference vs. evidence Evidence that supports theories Cm3 vs. mL Review how to calculate density!