Our solar system has eight planets that orbit (travel around) the sun. From closest to farthest: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. The four inner planets (Mercury, Venus, Earth, Mars) are small and rocky. The four outer planets (Jupiter, Saturn, Uranus, Neptune) are much larger and made mostly of gas and ice. Each planet is different -- some have moons, some have rings, and they vary greatly in size, temperature, and appearance.
Create a scale model of the solar system in a hallway or field to convey the vast distances between planets. Use a mnemonic for planet order (My Very Eager Mother Just Served Us Nachos). Show photographs of each planet and compare sizes -- Jupiter is so large that over 1,000 Earths could fit inside it. Discuss what makes Earth special (liquid water, atmosphere, life) compared to other planets.
Our sun is not alone in space. Traveling around it are eight planets, each following its own path (called an orbit) in a giant loop that takes them around the sun and back again. Together with the sun, these planets and other smaller objects make up our solar system.
The four planets closest to the sun are called the inner planets: Mercury, Venus, Earth, and Mars. They are all relatively small and made of rock and metal. Mercury is the smallest and closest to the sun, with scorching days and freezing nights. Venus is about the same size as Earth but has a thick atmosphere that traps heat, making it the hottest planet. Earth is our home -- the only planet known to have liquid water and living things. Mars is the red planet, with a thin atmosphere, rust-colored soil, and giant volcanoes.
Beyond Mars are the outer planets: Jupiter, Saturn, Uranus, and Neptune. These are the giants. Jupiter is the largest planet in our solar system -- so large that over 1,300 Earths could fit inside it. It has a famous red spot that is actually a storm bigger than Earth that has been raging for centuries. Saturn is known for its beautiful rings, made of billions of pieces of ice and rock orbiting the planet. Uranus and Neptune are smaller giants made of gas and ice, far from the sun and extremely cold.
What makes our solar system work is gravity -- the sun's gravity pulls on the planets, keeping them in their orbits, just as Earth's gravity keeps the moon orbiting us. Every planet orbits at a different speed and distance. Mercury zips around the sun in just 88 days, while Neptune takes 165 years to complete one orbit. The distances are hard to grasp: if you could drive a car from the sun to Neptune at highway speed, it would take over 5,000 years to get there. Our solar system is breathtakingly vast, and we live on a small rocky planet perfectly positioned for life within it.