Around and around we go with this interplanetary orbit quiz! Will you run ellipses ‘round these questions or will you find yourself tumbling back to Earth?

#1. In 1610, Galileo discovered moons orbiting a planet other than Earth. Which planet was he studying?

Jupiter! Using a homemade telescope to magnify the planet, Galileo tracked what looked like stars and found that they moved around Jupiter like moons. The four moons he tracked are the largest moons of Jupiter and are still known as the Galilean moons.

#2. True or false? Planets speed up and slow down as they orbit the Sun.

True! Planets have elliptical (oval-shaped) orbits they move slightly faster when they are closer to the Sun and slightly slower when they are furthest away.

#3. How many artificial satellites orbit the Earth?

More than 5,000. In fact, the United Nations lists almost 13,000 artificial satellites in Earth’s orbit! This is quite an increase from 1 artificial satellite, Sputnik, launched in 1957. Although Sputnik is no longer in orbit, the fourth satellite, Vanguard 1, is still up there!

#4. In an atom, what particles orbit the central nucleus?

Electrons orbit an atom’s nucleus in locations called orbitals. Atoms have a nucleus made of protons and neutrons, which stay at the centre of an atom. We made up satelliteons!

#5. In biology, an “orbit” is the part of the skull that holds an eyeball. Which of the following animals has the largest orbit?

Blue whales have eyes the size of grapefruit! Though this is very small compared to their overall body size. Owls have big eyes for their size, but a blue whale’s eye is bigger than most owls’ heads!

Was I right?


Congratulations! You are a real science whiz!

Oh dear! Better brush up before the next quiz!

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