Although space is a vacuum, it isn’t empty. If it was, you wouldn’t be reading this! The reason moons, planets and stars can move freely along their orbits is because space effectively has no friction.
The term ‘outer space’ is often used in science fiction novels to denote further afield than our current visible spectrum. It was first made popular in the stories of H G Wells in 1901.
Due to the density of Earth’s atmosphere gradually decreasing as the altitude increases, there is no fixed boundary between our atmosphere and space. However, NASA spacecraft shuttles change from steering with thrusters to manoeuvring with air surfaces at 76 miles (122 km). This distance is where atmospheric drag becomes noticeable.
Each quiz consists of 10 questions and each question has 4 multiple choice answers. At the top of each quiz you are given a choice of how you want to play it and this affects what happens when you provide an incorrect answer. You can either have the correct answer given immediately, or you can choose to have the questions presented again at the end of the quiz. To print any of the Key Stage 3 quizzes (both questions and answers) click the “Print” link at the bottom of the quiz.
