9 Weirdest Alien Worlds We've Already Found

Planets are created from the swirling disk of matter orbiting a new star. As the dust begins to clump together, planets are formed and, because they're are all formed from the same disk, they all move in pretty much the same way.

Pretty much, but not quite.

Whilst most of the planets in our solar system have got the whole rotating thing down, there are a couple that just can't seem to get the hang of it.

Uranus is essential "on its side" with the pole pointing towards the sun, meaning that how long a day is on the surface varies wildly between 17 hours and 42 years depending on where you are.

Venus has got the whole thing totally backwards. Whilst here on Earth, and on most other planets, the sun rises in the east and sets in the west because they spin anti-clockwise, on Venus, it's the other way around due to the fact that it is spinning clockwise, an effect known as retrograde rotation.

Not that you'd notice, because a day on Venus lasts longer than a year. It takes 225 days to make one full journey around the sun, but 243 days to rotate on its axis.

We're not quite sure what is was that confused these planets so much, perhaps a huge impact that knocked them permanently off balance, but there are probably countless freaks just like them out in the wider universe.