Download Lecture 2

“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 questions
How far away are the Sun and
Moon?
The Moon is 384 million meters
from the Earth (~250,000 miles).
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The Sun is 1.5x10 m 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
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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.