SOLAR SYSTEM MERCURY: is the smallest planet in our solar system. It’s just a little bigger than Earth’s moon. It is the closest planet to the sun. VENUS: it is still the hottest. It has a thick atmosphere full of the greenhouse gas carbon dioxide and clouds made of sulfuric acid. EAR TH: is a rocky, terrestrial planet. It has a solid and active surface with mountains, valleys, canyons, plains and so much more. Earth is special because it is an ocean planet. Water covers 70% of Earth's surface. MARS: is a cold desert world. It is half the size of Earth. Mars is sometimes called the Red Planet. It's red because of rusty iron in the ground. JUPITER : is the biggest planet in our solar system. It's similar to a star, but it never got big enough to start burning. It is covered in swirling cloud stripes. It has big storms like the Great Red Spot, which has been going for hu