1. The seasons 77

2. We´re going to talk about the seasons of the year.
A year is divided in 4 period of time called seasons.
We have four:
Spring- March to May.
Summer- June to August.
Autumn- September to November.
Winter- December to February

3. Many people believe that Earth is closer to the sun in the summer and that is why it is hotter. And, likewise, they think Earth is farthest from the sun in the winter.
Although this idea makes sense, it is incorrect.

4. It is true that Earth’s orbit is not a perfect circle
It is true that Earth’s orbit is not a perfect circle. It is a bit lop-sided. During part of the year, Earth is closer to the sun than at other times.
However, in the Northern Hemisphere, we are having winter when Earth is closest to the sun, and summer when it is farthest away!

5. Why do we have seasons? We have seasons because of this 3 things:
1- Earth´s axis is tilted.
2- The North pole always points the same way.
3- Earth’s movement around the sun

6. This axis is tilted an angle of 23,5 degrees.
Reason 1
The Earth is tilted:
Earth's axis is an imaginary line going right through the center of Earth from "top" to "bottom."
This axis is tilted an angle of 23,5 degrees.

7. But what caused Earth to tilt?
Long, long ago, when Earth was young, it is thought that something big hit Earth and knocked it off-kilter.
So instead of rotating with its axis straight up and down, it leans over a bit.
By the way, that big thing that hit Earth is called Theia. It also blasted a big hole in the surface. That big hit sent a huge amount of dust and rubble into orbit.
Most of the scientists think that that rubble, in time, became our Moon.

8. Reason 2 The North Pole always points the same way.
The Earth is always pointing to one side and it goes around the Sun. So, sometimes the Sun is in the direction that the Earth is pointing, but not at other times.
The tilt of the Earth means the Earth will lean towards the sun or lean away from the Sun

9. The Earth’s movement around the sun.
Reason 3
The Earth’s movement around the sun.
Earth move around the Sun in an elliptical orbit, that is known as “revolution”.  The Earth takes days to revolve around the Sun.

10. Hemispheres. (Northen and Southern.)
The Northern Hemisphere is the part of the Earth located above the Equator.
The Southern Hemisphere is the part of the Earth located below the Equator.

11. When the sun rays reaches vertically on the Earth give more heat and light, even being farther. The days are longer. It’s summer time.
When the sun rays reaches not so directly Earth, it´s colder. The days are shorter. It´s winter time.

12. If the north pole tilts towards the sun :
It is summer time in countries in the Northern Hemisphere .
it’s winter time in countries in the Southern Hemisphere.

13. If the north pole tilts away from the sun :
It is winter time in countries in the Northern Hemisphere .
it’s summer time in countries in the Southern Hemisphere.

14. Spring During Spring the Earth’s axis start to tilt towards the sun.
The days get longer and warmer.

15. Autumn. (Fall.)
During Autumn the Earth’s axis start to tilt away from the sun.
The days get shorter and cooler.

16. Thankyou for watching