Science SOL 4.8 Notes
4.8a Rotation or Revolution?


Rotation is the Earth spinning on its
axis
o One rotation takes 24 hours/1
day
Revolution is one body in space
orbiting another.
o The Earth revolves around the
sun in 365 days/1 year
o The moon revolves around the
Earth in about 28 days
4.8b Seasons
The seasons on Earth are caused by the tilt of
the Earth on its axis when it is revolving
around the Sun.
4.8c Phases of the Moon
4.8d Sun, Earth, Moon
 Sun:
o Average-sized, yellow star
o 110 times the diameter of
Earth
o approximately 4.6 billion
years old
 Moon:
o Small, rocky satellite
o 1/4 the diameter of Earth
o 1/80 the mass (weight) of
Earth
o Extreme temperatures
o Virtually no atmosphere
o Very little water
 Earth:
o Terrestrial planet
o About 150 million km from
sun
o Surface constantly
changes
o Large amounts of water
o Oxygen-rich atmosphere
o Protective atmosphere that
blocks out most of the
sun’s damaging rays
4.8e Historical Contributions
Astronomers:
 Aristotle and Ptolemy thought the
Earth was the center of the
universe
 Copernicus and Galileo believed
that the sun was the center of the
universe
Apollo Space Missions:
 The Apollo space missions added
to our understanding of the
moon.