Today, thanks to technological developments, such as the Keplar Telescope, we now know of thousands of exoplanets (planets orbiting a star that is not our sun).
Unlike the planets in our solar system, not all of these planets are a ball of rock or gas. Far from it, our universe is filled with planets that would be put science fiction novels to shame.
Some are wonders of chemistry, others are creepy and disturbing and some are just straight out bizarre.
Here are six of the strangest exoplanets known to man:
Credit: NASA
This planet may be a girl's best friend because it is one third diamond.
Due to the extreme pressure and heat from its parent star, the carbon based planet compressed into a gigantic diamond when it formed.
Forbes has estimated this planet is worth 28.9 nonillion US dollars (~$29, followed by 30 zeros).
But because diamonds are valuable because of their rarity, if you brought that much diamond back to earth, diamonds would no longer be rare and would become completely worthless.
This planet revolves around its' parent star so fast that one year on 55 Cancri e is equivalent to around 18 hours on earth.
This planet orbits its parent star at a distance 20 times greater than the distance that Neptune orbits the sun (about 60 billion miles).
This makes it one of the most isolated planets that we know of.
With all that distance to travel, HD 106906 b has an orbiting period (the time it takes to take 1 lap around its host star) of 3,000 years.
It is 11 times the size of Jupiter and has been given the nick name 'Super Jupiter'
Credit: NASA
This planet is proving to be a real head-scratcher for scientists.
Located 400 light years from earth, this planet boasts rings 200 times bigger than the rings of Saturn.
In fact, if Saturn's rings were the size of J1407b, they would be prominent in earth's sky.
J1407b's 30 odd rings are probably made of dust, as at 1,000 to 2,000 degrees Celsius, scientists believe it is too hot to support ice rings like those orbiting Saturn.
This planet is remarkable because it is located in a solar system with three stars.
While multi-star systems aren't uncommon, before this discovery, scientists believed planets could not live within this environment.
If you were standing on the surface of HD 188753, you would have three shadows, you could see the sunset, no matter what direction you looked in and you would regularly see solar eclipses.
Credit: NAOJ
42 light years away floats quite a remarkable planet.
GJ 1214b is a planet that has no land, it is entirely covered by water.
The massive ocean stretches miles deep to the planets core.
Scientists have nicknamed this planet 'Waterworld'.
You read that right... Yes, Gliese 436 b is a planet coated in ice which is perpetually in flames.
How is this possible?
Gliese 436 b orbits its' star at the extremely close radius of around 25 million miles. To put this in perspective, Mercury, which gets hot enough to melt lead, orbits the sun at 36 million miles.
The close proximity to its star, as well as the greenhouse effect has scientists predicting the surface area of the planet to be a staggering 822°F (439°C)
But astonishingly due to Gliese 436 b's huge atmospheric pressure, the water particles on its surface push together into a solid state, ice, and the result is this marvellous contradiction.
Credit: NASA