Last Friday one of the most ambitious explorations ever undertaken came to an end. The Cassini probe was launched in 1997. It then spent 6 years travelling to Saturn and a further 13 years orbiting the planet. In that time Cassini has sent back some amazing images and a whole load of information about the second largest planet.
Cassini’s mission was brought to an end when it ran out of fuel. Scientists programmed the craft to plunge into Saturn’s atmosphere where it burned up, rather than have it litter the planet’s beautiful ring system.
Cassini has taught us a lot about Saturn so, in memory of this historic craft, here’s a list of fun facts about Saturn, the real lord of the rings:
- As well as being the second largest planet, Saturn is the fifth brightest object in Earth’s skies. You can easily see Saturn with the naked eye and make out its rings with a decent telescope
- Saturn isn’t the only planet with rings. Neptune, Jupiter and Uranus have their own rings, though none are as impressive as those of Saturn. Most of the material in Saturn’s rings is frozen water
- So far we’ve found 62 moons orbiting Saturn. Only 53 have been named as the rest are very small. There are more than 100 ‘moonlets’ orbiting Saturn
- A year on Saturn lasts for 29.4 Earth years. Its days are short though. The planet rotates so quickly that sunrise and sunset are just 5 hours apart
- This rapid rotation makes Saturn the flattest planet. The distance from north pole to south and back again is 10% longer than the distance around Saturn’s equator. That’s due to the centrifugal force generated by the planet’s spin
- Saturn is the sixth planet from the Sun, some 1.5 billion km out and 1.2 billion km from Earth. This makes it very cold. Temperatures average at -212° Celsius. On Earth, the coldest temperature recorded is -89°
- Saturn is huge. About 750 Earths could fit inside it! Despite this, Saturn is not very dense so its gravity is just 1.08 times stronger than Earth’s
- One of Saturn’s moons, Titan, is larger than the planet Mercury. It also has a thick atmosphere and, were it not so cold, might have harboured life
There’s a lot more I could tell you about Saturn. Sadly, I’ve run out of space (if you’ll pardon the pun!). If you want to know more about the planets then you could start here. It’s an article I wrote last year, full of interesting facts about our astronomical neighbourhood. Go on, take a look – it’s out of this world!