Unit: Earth’s Motions, and

Seasons

Start a

new unit!

https://www.youtube.com/watch?v=EXasopxAFoM

Topic: Earth’s Motions

What are the two type of

motions that we are

experiencing right now?

Rotation= Earth spinning on its axis

Revolution = the movement of one body

around another ( the earth revolves

around the sun in space)

Rotation

Earth spins 15o/hr on its axis

1040 mph at the Equator

800 mph at our latitude

Looking down on the Earth's North Pole, it is rotatingcounterclockwise.

Evidence Earth Rotates!

1. focult pendulum 2. Coriolis effect 3. star trails

http://commons.wikimedia.org/wiki/Image:Foucault_pendulum_animated.gif

1. Foucault Pendulum

http://www.classzone.com/books/e

arth_science/terc/content/visualiza

tions/es0403/es0403page01.cfm?cha

pter_no=visualization

https://www.youtube.com/watch?v=jbh9_Sjw9K8MR. Wizard!!!!

https://www.youtube.com/watch?v=etJn6BZSejwPendulum in Museum

Star Trails

https://www.youtube.com/watch?v=tp6UkqI

wVfk

Coriolis EffectNorthern hemisphere objects

deflect:

RIGHT

Southern hemisphere objects deflect:

LEFT

https://www.youtube.com/watch?v=IMKa_ubu8UM

Navigators must allow for deviation to right when flying in northern hemisphere -- and to left in southern hemisphere.

The rotation of the earth creates special problems on flights to and from the moon.

1) Rotation (Counterclockwise) Spins on axis 15°/hr

Evidence

1) Foucault pendulum

2) Coriolis Effect

3) Star trails

Effects: day/night

Sidereal Day—ESRT pg 15

RevolutionSun

Fastest human = ~18 mph

Cheetah = 46 mph

Fastest car = 350 mph

Planes = up to 2,200 mph

Earth revolves around sun = 67,000 mph

Constellations

ESRT pg 15

2) Revolution • Completes an orbit around the Sun, about 1° of motion per day

Evidence

1) Change in constellationsPeriod of revolution

365.26 days

FQ:

What causes the Coriolis Effect?

How does it affect the Northern Hemisphere?