Edible planets

•  Do the same activity as the Solar System Scale Model - this time using food.

• Add a large pumpkin or watermelon (a round one if possible) at the beginning of the line to represent the Sun.

• The result is a reasonable model of the relative size of the planets in our Solar System.

• To add extra authenticity to the model, add a few grains of rice for moons and a stretch of sand as the asteroid belt between Mars and Jupiter.

Background Information

The nine planets of the solar system can be divided into two groups: the rock-like or terrestrial planets and the gas giant planets, also called Jovian planets. The rock-like planets are the inner planets - Mercury, Venus, Earth, Mars, along with distant Pluto. They are also the smaller planets. The gas giant planets - Jupiter, Saturn, Uranus, and Neptune - are much larger and have no solid surface on which a spaceship could land. Jupiter is the largest planet in the solar system.

Earth is 150 million kilometres from the Sun. More distant planets such as Neptune and Pluto are billions of kilometres from the Sun. These distances alone begin to explain the difficulties space travel presents. The distance a planet is from the Sun affects the temperature of that planet. For example, Mercury and Venus are relatively close to the Sun. The Sun heats up these planets to temperatures up to and beyond 450°C. Pluto, being the furthest from the sun, is the coldest planet of all. A planet's distance from the Sun also affects how fast it travels. The closer a planet is to the Sun, the faster the Sun's gravity pulls the planet around in its orbit.