Temperatures go up to 500 °C when it faces the sun and -150°C on its dark side. Some scientists believe that Mercury is really the moon of another planet that flew off course and began its own orbit as a planet.
The surface of Mercury is very much like that of the moon. The orbit of Mercury is egg-shaped - which means it is closer to the sun at some times of the year.
They believe that if we put plants on the planet that produce oxygen there would be an atmosphere that we could breathe.Like the earth, Venus is covered with thick clouds and has an atmosphere.There is almost the same amount of gravity on Venus but the pressure on the planet is about 100 times bigger than on Earth.And human beings might be able to start a colony on Venus.Venus was named after the goddess of love and beauty. The Moon is the closest astronomical body to the Earth and we know more about it than about any other object in the heavens.