1. Homework: Tides
Tide = the rising and falling of ocean waters as
a result of the Moon’s gravity and Earth’s gravity
The Moon is held in orbit around
the Earth by gravity, Moon’s
gravity is pulling on Earth, Earth’s
gravity is pulling on the Moon
The tides are caused by a
difference in gravitational pull
from the Moon on opposite sides
of the Earth.
3. Homework: Auroras
Result from solar wind hitting the Earth.
Can disrupt telecommunications and
overload electrical power networks.
When the high-energy charged
particles are carried past Earth’s
magnetic field they generate electric
currents that flow toward Earth’s poles.
Electric currents charge gases in the
atmosphere and produce light.
6. Planetary Motion
Orbit = the path of one object revolving around
another
Revolution = the time it takes for an object to orbit
another object
i.e. Earth’s revolution is 365.24 days
7. Planetary Motion
Rotation = the turning of an object around an
imaginary axis running through it
i.e. Earth’s rotation is approximately 24 hours
8. Planetary Motion
Retrograde motion is the movement of a planet
from east to west in the sky, rather than its
normal motion from west to east
Image:
Shows
Retrograde
motion of
Mars
