Movement of Earth Why do our seasons change?. Rotation V/S Revolution Rotation is the spinning of a moon or planet on its AXIS Revolution is planets movement.

Movement of Earth

Why do our seasons change?

Rotation V/S Revolution

Rotation is the spinning of a moon or planet on its AXIS

Revolution is planets movement around a star or moons movement around a planet.

Rotation

Viewed from above our solar system, Earth Rotates once every 23 hours and 56 minutes. Because we are also revolving, from our perspective on Earth it rotates once every 24 hours, this is the length of our day.

Earth’s Rotation causes day and night.

Our Moon rotates once (3600) every 27 days, 8 hours 27.3 days

RevolutionRevolution is a planets movement around a star or

a moons movement around a planet.

The path of that planet or moon is called an

orbit.

All planets in our solar system have an

Elliptical orbit, (more oval than round)

Earth and Moon’s Revolution

Our Moon’s revolution period is 27.3 days, this is why we see moon phases.

Because our Moon’s rotation and revolution periods are the same, we always see the same side of our Moon!

Earth’s revolution period is 365.25 days

2. The tilt of our Earth

The imaginary line that runs through Earth’s poles is called its axis.

Earths axis is tilted 23.50

3. Seasons change due to the tilt of Earth and

Revolution around our Sun.

When either the northern or southern hemisphere receives more sunlight, the temperatures increase, when it receives less sunlight, the temperatures decrease.

Less sunlight= Winter More sunlight= Summer

4. Solstices and Equinoxes

Winter Solstice occurs on December 21-22, we receive the shortest length of sunlight hours.

Summer Solstice occurs on June 20-22, we receive the longest length of sunlight hours.

Equinoxes occur on March 20-21 and on September 22-23, the equator receives 12 hours of light and 12 hours of darkness.

5. Apogee and Perigee

When the moon is closest to Earth it is

called Perigee

When the moon is farther from Earth it

is called Apogee

6. Aphelion and PerihelionWhen Earth is closest in orbit to the Sun is is

called Perihelion, this is during our winter.

When Earth is farthest in orbit from the Sun is is called Aphelion, this is during our summer.