EnviroKids October 2018 Issue

Sun, Our Star The Brightest Star in Our Sky

Moon

Our

To the

and Back

The Sun is the star at the centre of our Solar System. It is about 110 times bigger than Earth. Around three quarters of the Sun is made of hydrogen, while the rest is mostly helium. Without the Sun, we could not survive, and it is the most important source of energy for life on Earth.

Meet Earth’s Satel lite The Moon orbits the Earth and is our only natural satellite. It is thought to be around 4.51 billion years old, making it only slightly younger than the Earth. Scientists theorise that the Moon was created from the leftover debris when Earth and another planet-like body called Theia collided.

The Sun is about 150 million kilometres away from the Moon.

Photo what? Photo means light, and synthesis means mixing.

Photosynthesis is the way in which plants use energy from the Sun as well as water, and carbon dioxide to create oxy- gen and grow. Photosynthesis is a chemical reaction that takes place within a plant, creating glucose. This glucose gives the plant energy to grow and sur- vive, and to produce oxygen for animals and humans on Earth.

What is a Moon? Moons are rocky bodies that orbit planets and are also called satellites. Some planets have no moons, like Mercury and Venus, while others have many, like Jupiter (64 moons). Our Moon is about 384 000km from Earth, making it the biggest object we can see in our night sky.

Did you know? 12 astronauts have walked on the Moon since 1969.

Once in a Blue Moon A blue Moon occurs in rare conditions, such as if volcanic eruptions or fires leave particles in Earth’s atmosphere, causing the Moon to appear blue.

Spinning in Space Have you ever wondered why we only see one side of the Moon? Just like the Earth, the Moon has an axis around which it rotates. This rotation takes 28 days. The Moon also orbits around the Earth, which takes 28 days. The speed of the rotation is the same speed of the Moon’s orbit, which is why we only ever see one side of it.

From East to West From Earth it seems as if the Sun moves from one side to another during sunrise and sunset, but it is in fact Earth that moves around the Sun. It takes Earth one year to travel around the Sun, but while it does so, it is also rotating on its own axis. These two movements are what cause seasons (Spring, Summer, Autumn, Winter). These two movements are also what cause night and day. At certain times of the year, Earth is further or closer to the sun. When Earth is clos- er to the Sun it is warmer, and when it is further away, it is cooler.

Did you know? • Our Moon does not produce its own light. Instead, it reflects light from the Sun. • The craters we see on the moon were formed by asteroids and other objects crashing into it. • The Moon has no atmosphere and gravity, which is why astronauts float about on its surface. • The Moon has its own shakes! Just like earthquakes, our satellite experiences moonquakes, which are less intense than the ones on Earth and are thought to be caused by tidal stresses from the varying distance between the Earth and Moon.

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