Summary
Highlights
The video begins by debunking the idea that the sun moves during sunrise and sunset, explaining that it's actually the Earth that is continuously rotating and revolving. It sets out to explain Earth's rotational and revolutionary movements.
Earth's rotation is defined as its spinning movement around an imaginary line called an axis. This rotation is responsible for day and night. When a part of the Earth faces the sun, it's daytime, and when it spins away, it's nighttime. One full rotation takes 24 hours, making a single day.
While rotating on its axis, Earth also revolves in an orbit around the sun. This movement is called revolution. One full orbit around the sun is one revolution and takes approximately 365.242 days, which makes up a whole year. Rotation refers to movement around an axis (day and night), while revolution refers to one body moving around another (a year).
The Earth's axis is not straight; it is tilted. This tilt was caused by an ancient crash with a Mars-sized object. This axial tilt means that different parts of the Earth lean towards or away from the sun throughout the year, causing the amount of solar energy received to vary. This variation is why we experience different seasons, and why seasons are opposite in the Northern and Southern Hemispheres. The part leaning towards the sun experiences summer, while the part leaning away experiences winter.