| A | B |
|---|
| Which planet is closest to the sun? | Mercury |
| How many Earth days does it take Mercury to complete one revolution around the sun? | 88 |
| Because Mercury has almost no atmosphere, it has no ____?_______ | weather |
| Why has the surface of Mercury stayed the same for billions of years? | It has no rain, snow, or wind to erode the planet |
| How were the plains on Mercury created? | Ancient volcano flows |
| How many Earth days does it take for Mercury to rotate once on its axis? | 59 |
| Is Mercury one of the hottest or one of the coldest planet? | Both |
| Venus is covered with dense clouds, what are they made of? | sulphuric acid and carbon dioxide |
| Has water been discovered on Venus? | No |
| Which planet is called the Greenhouse planet? | Venus |
| Name the planets with retrograde revolution. | Venus and Uranus |
| What is a greenhouse effect? | When heat becomes trapped beneath the clouds. |
| Name the moons that circle Mars. | Deimos and Phobos |
| What spacecrafts landed on Mars? | Viking 1 and Viking 2 |
| Name the largest Volcano on Mars. | Olympus Mons |
| What are asteroids made of? | rock and metal |
| Name the largest asteroid. | Ceres |
| How many Earths could circle Jupiter? | 100 |
| Name the two spacecraft that flew past Jupiter. | Voyager 1 and Voyager 2 |
| Name the four moons of Jupier | Io, Europa, Ganymeade, Callisto |
| What are Saturn's rings made of? | icy particles |
| Why is Saturn elliptical? | It spins fast |
| Name Saturn's largest moon. | Titan |
| Why does it seem Uranus is tilted on its side? | Its axis is tilted at an angle of 90 degrees |
| What is unusual about Neptune's moon Triton? | It orbits backwards |
| Name the moon of Pluto. | Charon |
| What is the Oort cloud? | a vast collection of ice and dust where comets are believed to be formed |
| Name the core of a comet. | Nucleus |
| What is a coma? | a cloud of dust and gas surrounding a comet |
| What is the head of a comet made of? | The coma and the nucleus |
| What is a comet called that takes thousands of years to orbit the sun? | Long period |
| What is a comet called that orbits the sun every few years? | Short period |
| What is a meteor called that strikes the Earth? | Meteorite |
| Name all the planets that have life in our solar system. | Earth |
| What is Sir Isaac Newton's 3rd law of motion? | Every action produces an equal and opposite reaction |
| What is thrust? | the force of forward movement that causes a rocket to shoot forward |
| What things determine escape velocity? | Mass of the planet and the distance of the rocket from the planet's center |
| What is velocity? | Speed |
