Earth In Space
The study of are atmosphere, is called astronomy. We study space, to find out if there are any asteroids, or new planets, with existing life on it. Earth rotates on its axis, and when it rotates around, it can be recognized as a rotation, or a revolution. A revolution is when something is rotating around another object, like how the earth rotates around the sun. Earth follows a path around the sun, this is called an orbit. The calender is based off of the suns rising point, and its setting point. Places outside of the tropics and polar regions, and they have four seasons, winter, spring, summer, and autumn. The day, when the sun is farthest north or south of the equator, is called a solstice. If it is at the North, it will be summer in the Northern hemisphere, and in the Southern hemisphere, it is winter. An equinox, is when the noon sun, is directly overhead the equator. This happens every two years, and means equal night.
Gravity and Motion
The earth revolves around the sun, Newton realized that the force that holds the moon in orbit , is the gravity. Gravity attracts all objects toward each other. Inertia, we feel it everyday. When you are in a car, and it comes to a stop, your body keeps on moving forward. This has to do, with newtons first law of motion. His theory was, that an object at rest will stay at rest, and an object in motion, will stay in motion.
Phases,Eclipse, and Tides
What causes the phases of the moon? The phases of the moon are caused by how much of the sunlit side of the moon faces Earth.
What are solar and lunar eclipses? A solar eclipse occurs when the moon passes directly between Earth and the sun, blocking sunlight from Earth. A lunar eclipse is when Earth blocks sunlight from reaching the moon.
What causes the tides? Tides are caused by differences in how much the moon's gravity pulls on different parts of Earth.
Features of the moon's surface include; maria, craters, and highlands. Maria is dark, flat areas on the moon's surface. Craters are large round pits. Highlands are like mountains and they're light colored features. The size and density, the moon is 3,476 kilometers in diameter. This is a little less than the distance across the United States. It's also about one-fourth of Earth's diameter. The moon's mass is only one-eightieth of Earth's mass. Temperature and Atmosphere...temperatures range from 130°C to -180°C. And the reason why the temperatures on the moon vary so much is because the moon has no atmosphere. There is no liquid water on the moon. But, there is some evidence that there may be some large patches or ice near the moon's poles.