Presentation on theme: "Why do our seasons change?"— Presentation transcript:
1 Why do our seasons change? Movement of EarthWhy do our seasons change?
2 Rotation V/S Revolution Rotation is the spinning of a moon or planet on its AXISRevolution is planets movement around a star or moons movement around a planet.Rotation V/S Revolution
3 Rotation Our Moon rotates once (3600) every 27 days, 8 hours 27.3 days 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.
4 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)
5 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 days
6 2. The tilt of our EarthThe imaginary line that runs through Earth’s poles is called its axis.Earths axis is tilted 23.50
7 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
8 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 and on September 22-23, the equator receives 12 hours of light and 12 hours of darkness.
9 5. Apogee and PerigeeWhen the moon is closest to Earth it is called PerigeeWhen the moon is farther from Earth it is called Apogee
10 6. Aphelion and Perihelion When 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.