4th grade-ch. 17 lesson 1 how does earth move
Post on 11-May-2015
4.933 Views
Preview:
TRANSCRIPT
Ch. 17 Ch. 17 Lesson 1Lesson 1How does How does
Earth move?Earth move?
clues that Earth clues that Earth is moving:is moving:
1.1. Sun & stars seem to Sun & stars seem to move across skymove across sky
2.2. change of seasonschange of seasons
Why can’t you feel Why can’t you feel Earth’s movement?Earth’s movement?
Earth moves Earth moves steadily & smoothlysteadily & smoothly
axisaxisimaginary line that runs imaginary line that runs thru. North Polethru. North Pole Earth’s Earth’s ctr.ctr. South Pole South Pole
tilt of Earth’s axistilt of Earth’s axis
causes causes seasons seasons to changeto change
The Earth's Tilt on Its Axis and the Seasons [02:15]
rotationrotationspinning spinning motion of motion of Earth on Earth on its axisits axis
rotrotaationtionxxiiss
rotationrotation23 hours & 56 min. 23 hours & 56 min.
rotationrotationcauses day & nightcauses day & nightEarth rotates from Earth rotates from westwest east east
Earth's rotation animation
revolutionrevolutionmovement of one movement of one object around anotherobject around another
Rotation-Revolution animation
Rotation & RevolutionRotation & Revolution
The Movement of the Earth [04:18]
orbitorbitpath Earth takes as it path Earth takes as it revolves around Sunrevolves around Sun
Force of gravity Force of gravity keeps Earth in its keeps Earth in its orbit.orbit.
ellipse (elliptical)ellipse (elliptical)Shape of Earth’s orbitShape of Earth’s orbitStretched out circle Stretched out circle (oval)(oval)
Rotation and Revolution quizRotation and Revolution quiz
1. What is an axis? 1. What is an axis? 2. The Earth _____around the Sun.2. The Earth _____around the Sun.3. The Earth _____on its axis.3. The Earth _____on its axis.4. Does the Earth rotate and 4. Does the Earth rotate and revolve at the same time?revolve at the same time? Explain your answer.Explain your answer.5. How would Earth be affected if 5. How would Earth be affected if its axis weren’t tilted?its axis weren’t tilted?
top related