Earth Dances
The Earth revolves around the Sun every 365 days, and this is why our calendar has 365 days in a year. That means the Earth, on its orbital path, moves completely around the Sun one time each year. So why does the Earth orbit the Sun? The motion happens because of something called gravity. Gravity is a force of attraction between two objects that have mass. The object with more mass pulls things towards it. Since the Sun has much more mass than the Earth, the Earth is pulled toward the Sun. Gravity is the same force that pulls us to the Earth and keeps our feet on the ground.
If the Sun is pulling the planets, why don't they just fall into the Sun and burn up? Well, in addition to falling toward the Sun, the Earth and the other planets are also moving sideways. Without that sideways motion, Earth would fall to the center; and without the pull toward the center, Earth would go flying off in a straight line. The two forces work together to create an orbital path.
Earth's orbital path is created by two things: gravity and a sideways motion
The Earth also has an axis, and it rotates on its axis every 24 hours. This is why there are 24 hours in a day. Revolution is when the Earth moves in a circle around the Sun, and rotation is when the Earth spins on its axis. Because the Earth rotates one time every 24 hours, at any point in a day, half of the Earth is facing the Sun and half of the Earth is facing away from the Sun. In North America, we have daytime when our continent is facing the Sun. North America has nighttime when our continent is on the side of Earth facing away from the Sun. So, when it is nighttime in North America, it is daytime in places on the other side of the Earth.
Entry 5: Can you find an example of a country that is experiencing nighttime when you are experiencing daytime? Record the country in your log. Write a paragraph about 1) what you are doing at 8:00am and 2) what a boy or girl your age in that country might be doing at that same moment.