By now you have probably become an expert on comparative planetology. What is it? It is when astronomers study two worlds which are similar to help them understand the planets better. This week we are going to study the planets Jupiter and Saturn.
What do these planets have in common?
First of all, they are easy to see with a telescope or binoculars. They are bright, and they are both very pretty. Jupiter is a bit brighter than Saturn because it is bigger, as well as closer to us.
Jupiter and Saturn are the largest planets in the Solar System. Jupiter is 1318 times more voluminous than the Earth. This means it takes up 1318 times as much space as does the Earth. Saturn takes up 744 times as much space. Although Saturn is very big, Jupiter is actually much bigger. In fact, Jupiter is bigger than Saturn and all the other planets put together.
Because these planets are so large they have very strong gravity. The strong gravity sometimes captures asteroids making them moons. Both planets have more moons than the number of planets in the Solar System. Many of these moons are small and are probably captured asteroids, but some are huge. Some of them are even bigger than the planets Mercury and Pluto.
The atmospheres of Saturn and Jupiter are almost identical. Both have high levels of hydrogen, helium and methane. Jupiter is almost twice as close to the Sun than Saturn, however, and is much warmer. Because it is warmer, there are visible storms in the cloud tops. Saturn probably has similar storms, but they are deeper in the atmosphere where it is warmer and where we cannot see them.
The first people who looked at Saturn with a telescope thought that it had giant ear-like bulbs. This is because the telescopes they used were not powerful enough to produce a clear image to see that what looked like bulbs were really rings. If you look at Saturn with your binoculars you will see that it is shaped like a lemon.
Saturn is not the only planet with rings. Jupiter, Uranus and Neptune all have rings as well.
Assignment # 1:
Name three ways that Jupiter and Saturn are similar.
Is Saturn the only planet with rings?
Check your answer
Both Have Many Moons
Both Have Rings