“I bet a fun thing would be to go way back in time to where there was going to be an eclipse

and tell the cave men, “If I have come to destroy you, may the Sun be blotted out from the sky.” Just then the eclipse would start, and they'd probably try to kill you or something, but then you could explain about the rotation

of the Moon and all, and everyone would get a good laugh.”Jack Handy

http://sdbv.missouristate.edu/mreed/CLASS/A113Sp16

Notices:Readings updated: Use the readings to

supplement your understanding. Everything you need to know will be covered in class.

Please keep your cell phones, tablets, and computers put away- I would like your

attention for these 50 minutes.

Intro questions

How big is the Earth?The Earth is about 6.4 million

meters in radius.

Intro questions

How far away are the Sun and Moon?

Intro questionsHow far away are the Sun and

Moon?The Moon is 384 million meters from the Earth (~250,000 miles).

The Sun is 1.5x1011m from Earth (150 billion m, or ~93 million

miles). This distance is called 1 astronomical unit (AU).

A picture of our solar system.

Order by size:Earth, Moon, Sun, Stars, Comets, Planets

A picture of our solar system.

Order by size:Earth, Moon, Sun, Stars, Comets, Planets

How could you determine these sizes?

What is at the center of our solar system?

What is at the center of our solar system?

The Sun

(Could you prove it?)

What is science?

understanding the world around us using observation, experiment, and deductive reasoning.

The scientific method

➲ Do an experiment or make an observation.➲ Determine an explanation (theory) for the

observation.➲ From the theory, make predictions.➲ Make further observations to test the

prediction.➲ Eliminate or refine the theory.