1. Atmosphere

2. The sun is the major source of energy for all natural events on Earth. 

3. The sun is the major source of energy for phenomena on the Earth's surface, including winds, ocean currents, and waves. 

4. An atmosphere is the mixture of gases that surrounds a planet, such as Earth. 

5. Our atmosphere absorbs the radiation from the sun, heating the earth.

6. Nitrogen and Oxygen are the two most prevalent gasses in Earth’s atmosphere.

7. The atmosphere is made up of 78% Nitrogen, 21% Oxygen, and 1% other gasses.

8. List the 5 layers of the atmosphere in order.
Troposphere
Stratosphere
Mesosphere
Thermosphere
Exosphere

9. The Troposphere is the densest layer and it contains approximately 90% of the mass of the entire atmosphere.

10. All weather occurs in the Troposphere

11. The Stratosphere contains the ozone layer which protects the planet from the sun’s radiation.

12. The Mesosphere is the coldest layer of the atmosphere.

13. The Thermosphere has the most energy of any other layer of the earth’s atmosphere. This layer absorbs the most radiation from the sun.

14. The exosphere is the uppermost region of Earth's atmosphere as it gradually fades into the vacuum of space.

15. Air in the exosphere is extremely thin - in many ways it is almost the same as the airless void of outer space.

16. As altitude increases, the density of the air decreases.

17. Airplanes fly faster in higher altitudes because the air is less dense.