Earth, Moon, and the Sun
by Frank Hegedus
Chapter 1: Earth, Moon, and Sun
Section 1: Earth in Space
In this section, we will learn about how the Earth moves in space. Also, we will learn about why there is a cycle of seasons, and how that came to be.
How does Earth Move in Space?
The Earth moves in two specific ways, rotation, and revolution. Rotation is when the Earth spins on it's axis. This action takes a day, or 24 hours. Revolution is when the Earth moves around the Sun. This action takes a year and 1/4 of a day.
What causes the cycle of seasons on Earth?
The cycle of Season's on Earth is caused by the tilt of Earth's axis as it revolves around the sun. Since the Earth is tilted, different places on the Earth get different amounts of sunlight. When it is Winter in the Northern Hemisphere, the Northern Hemisphere is pointed away from the sun, while the Southern Hemisphere is angled toward the sun, and vise versa for summer in the Northern Hemisphere.
Section 2: Gravity and Motion
In this section we will learn about how gravity and motion work. We will also learn how the force of gravity is affected by other factors. Also, we will see how the Earth and the Moon move in space, and what keeps them in orbit.
What determines strength of the force of gravity between two objects?
Two major factors that determine the strength of the force of gravity between two objects are mass and distance. Mass is the amount of matter in an object. If the amount of mass increases, the force of gravity increases. If distance increases, then force decreases. The force of gravity on an is also called the objects weight.
What two factors combine to keep the moon and the Earth in orbit?
The two factors that keep the moon in orbit around the Earth and Earth in orbit around the sun are inertia and gravity. Inertia is the the tendency of an object to resist a change in motion. This can be shie in Isaac Newton's first law of motion, an object at rest stay at rest and an object in motion will stay in motion with a constant speed and direction unless acted in by a force. Because of inertia, the moon keeps revolving around the Earth. But because of gravity, the moon doesn't fly off into space, it hold the moon in orbit.
Section 3: Phases, Eclipses, and Tides
In this section we will learn about the phases of the moon, eclipses of the moon and sun, and what causes the tides. We will learn what causes the moon phases, and what causes the eclipses.
What causes the phases of the moon?
The moon phases are cause because of how the Earth moves around the sun in revelation to how the moon moves around the Earth. Since the Moon reflects sunlight it glows at night and we can see it, however since the same side of the moon is always facing Earth, different amount of sunlight is hitting that face at different times, hence the phases we get.
What are solar and Lunar eclipses?
An eclipse is the partial or total blocking of one object in space by another. There are two kinds of eclipses, solar and lunar. Lunar eclipses take place when the moon, fully or partially, dips into Earth's shadow, and appears as a new moon, but not when it is supposed to happen. Solar eclipses are when, during a new moon, the moon passes directly between the Earth and the Sun, blocking the sun from view, but not all of it. If you look at a solar eclipse, it is like looking straight at the sun because some of the Sun's Rays go around the moon, so you must wear eclipse glasses, even during a full eclipse.
What causes the tides?
Tides are caused by how much the moons gravity pulls on different parts of Earth. On the side of Earth with the moon, the gravitational pull on the water is stronger than the gravitational pull on the Earth itself, so the water flows there, causing hide tide. On the other side of Earth, the opposite happens with the same result. The gravitational pull on Earth is greater then the water so the Earth moves toward the moon, and the water is "left behind" and high tide forms there. On the other points of Earth, the water flows away from those points, causing low tide there.
At 9:15 am ET the High tide occurs at East Wittering on April 22, 2015.
Section 4: Earth's moon
In this section, we will learn all there is to learn about the moon and it's surface. Features, characteristics, and how it formed.
What features are found on the moon's surface?
There are a variety of features on the moons surface such as maria, craters, and highlands. These features were discovered by Galileo Galilei ( I share a birthday with him!). Marias are the Latin word for "sea" because Galileo thought these were seas on the moon. He was incorrect and actually those darker spots on the moon are hardened rock formed by lava flows billions of years ago. Craters are large round pits in the surface of the moon caused by meteroids impacting billions of years ago. The surface of the moon still bears these marks, unlike the Earth, because the moon has no atmosphere or water to wear away the craters. The highlands, or lighter places, on the moon are mountain tops. These rugged places cover most of the moons surface.
What are some characteristics of the Moon?
The moon is very small and has large variations of surface temperature compared to the Earth. On the day side of the moon, temperatures can get to 130 degrees Celsius, roughly 228 degrees Fahrenheit. On the dark side of the moon, temperatures can get down to -180 degrees. The diameter of the moon is 3,476 kilometers, that is just less than the width of the USA. The moon is also not very dense, it is roughly the same as the top layer of the Earth. There is no liquid water on the moon, however, there is ice at the moon's poles and inside some craters.
How was the moon formed?
There are many theories on how the moon was formed and where the moon was formed. For example theories state that the moon might have been made somewhere else in the solar system and became captured by Earths gravity. However the best theory is called the collision- ring theory. This theory states that when the Earth was still very young, a planet-sized object collided with Earth and Earths outer layers thrusted into space. They were captured by Earths gravity and it caused the material to form into the Moon.
RSVP to the next total solar eclipse which is on March 8, 2016. The eclipse will be a total solar eclipse visible from from Sulawesi and other areas in the Pacific Ocean.