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

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

3. 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!)

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

5. THINGS IN SPACE ARE BIG!

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

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

9. Celestial body = astronomical object
Naturally occurring things or structures that we find in space
Let’s look at some!

10. 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)

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

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

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