The Solar System
The solar system that is home to planet earth is composed of a star, which we call the sun, and the surrounding celestial bodies which are pulled by the sun's gravity. The objects that surround the sun are the eight planets, dwarf planets, and two belts of small bodies. The solar system is a lot more complex than most kids and science classes will ever study. Some scientists spend their whole lives studying the solar system alone, and are still not able to understand all of its parts.
Planet earth, our planet, is among the first four planets closest to the sun whose orbits around the sun are almost circular. Kids and science classes are usually shown a circular planetary orbit, and this is not entirely accurate. All planets are slightly elliptical in their orbit around the sun. These four inner planets are called terrestrial planets, and they are Mercury, Venus, Earth, and Mars, in that order. Terrestrial planets are called such because they are mostly made of rock and metal, and so to is the asteroid belt that comes right after Mars and seemingly divides these inner planets from the outer ones. Among these four inner planets, only Earth and Mars have satellites orbiting them or that are drawn to its gravity. Earth's moon is the largest of the satellites, while Mars' two moons are smaller.
After the asteroid belt, the outer planets or the gas giants orbit the sun. They are called giants because they are so much larger than the inner planets. These four gas planets are Jupiter, Saturn, Uranus, and Neptune. All the gas giants have hydrogen and helium in them, and have rings of space particles and dust that surround them and are attracted to its orbit in the same way that satellites are pulled into a planet's orbit. However, most kids and science classes only study Saturn's rings because these are clearly seen from Earth. All the outer planets also have satellites or moons orbiting them. The one with the least being Neptune which has thirteen, and the most is Jupiter with sixty-three.
Remaining parts of the solar system are the dwarf planets, Pluto, Ceres (part of the asteroid belt, but large enough to be considered a dwarf planet), Haumea, Makemake, and Eris, in that order. Dwarf planets are rounded because their gravity was enough to round them out and make them appear like planets. These planets are all found near the Kuiper belt, a belt of ice and space debris that is beyond Neptune and is also affected by the sun's gravity. Most kids and science classes only study the asteroid belt, perhaps because it is closest to earth, but the Kuiper belt is very much a part of the solar system, similar to the asteroid belt.
In the project section, you will be asked to make a working model of the solar system. You can make it as detailed as you can, or as this article discusses, but what is important is that the eight planets are represented well, and are able to orbit the sun.
