You’re watching freeschool! Our Solar System Have you ever looked up into the sky and wondered what was there? Higher than the birds, past the clouds, and farther than the moon, a whole host of fascinating objects spin in outer space. Let’s imagine for a moment that we can leave the earth behind, and explore the solar system that surrounds it.
We call it the solar system because everything in it is centered around the sun, and solar means something to do with the sun. The sun is a star, just like many of the stars that you can see in the night sky just many times closer to us. Still, the sun is very, very far away from the earth; almost 93 million miles away: that’s why it looks so small, even though it’s the biggest object in the solar system. In fact, the sun makes up more than 99 percent of the mass in the solar system. If you put all of the planets, moons, asteroids,.
Comets, and everything else in the solar system together, they would make up less than one quarter of a percent of it. The sun is so big that it’s more than 100 times wider than the earth, and if it were a giant jar you could fit more than one million earths into it. More than that, the sun is what holds the solar system together. Its massive gravity is what keeps the earth and all the other planets circling around it instead of drifting.
Off into space. The sun is also what allows us to live on Earth. Without the sun, there would be no heat. There would be no light. Plants could not grow, water would freeze, and nothing could survive. The sun gives us heat and light because it is always burning: it is a giant ball of gas, mostly hydrogen and helium, and it burns at millions of degrees in its center. Let’s leave the sun now to explore the planets.
As we move away from the sun, the first planet we will encounter is mercury. mercury is the smallest planet in the solar system, much smaller than earth, and one of only five planets you can see from earth using nothing but your eyes. Of course, it won’t look much like a planet. It looks more like a bright star, and many nights you can see it close to the horizon near sunrise and sunset. Mercury is a lot like our moon. It’s small and has a rocky surface with craters on it.
It has no moon of its own, and no air to breathe. you probably wouldn’t enjoy a visit to mercury, since temperatures are boiling hot in the sun and freezing cold in the shade. Something interesting about mercury is that it is the fastest planet to go around the sun it only takes 88 days. Next is Venus, the second planet. Some people call venus earth’s sister, because the two planets are very close in size and gravity, but they are very different on the surface.
First of all, it is very hot. venus is the hottest planet in the solar system. it’s not as close to the sun as mercury, but its thick atmosphere of carbon dioxide helps it to trap the heat and stay warmer than its neighbor. It has a thick atmosphere, but it is not one you could breathe. It is mostly made of carbon dioxide and there are clouds of sulfuric acid! Venus might not be fun to visit, but it is beautiful to lok at. It is the secondbrightest object in the night sky the only thing brighter is the moon. If you are looking at a sunrise.
Or a sunset and suddenly notice what looks like a very bright star, you are probably looking at Venus. After Venus comes Earth, the third planet from the sun. Of course, you know all about Earth, because that’s the planet where we live! Earth is what’s called a ‘goldilocks planet,’ because it’s not too hot, and not too cold it’s just right. As far as we know, Earth is the only planet to have living things.