In 1974 scientists sent the Mariner 10 probe to visit Mercury.
Mercury has almost no atmosphere.
Venus is about the same size as Earth.
Venus days are 243 Earth days.
Earth is the only planet with an atmosphere.
The Earth has only one moon.
Jupiter is a gas giant.
Jupiter's atmosphere is mainly hydrogen and helium.
The Voyager space probe explored Saturn's rings.
The rings are probably made of ice, dust and chunks of rock.
Uranus has a ring around its center.
Uranus is the farthest planet you can see without a telescope.
Neptune could hold 60 Earths if it was hollow.
Neptune takes more than 100 Earth years to orbit the sun.
Mars - The Aliens Home Planet
Mars nickname is the Red planet.
Mars has 2 moons.