Caution: Pictorial answer here-
There is a moon out there, very similar to earth. It comprises of oceans, lakes, rivers, mountains and a hydrological cycle (rain cycle).
“Then why is Elon Musk planning his colony on Mars?”, you may ask.
The only teeny tiny problem is that all the lakes, rivers, oceans and even rains are of Methane and ethane.
The name of the moon is Titan (not where Thanos is from). It is a natural satellite of Saturn.
A day on Titan may look like this.
- You could fly in its sky
Titan’s thick atmosphere, low gravity (less than our Moon) and reasonable surface pressure (50% of Earth’s) mean that, by flapping a pair of wings strapped to your arms, you could fly in its skies with no more effort than walking.
- It’s the only other world with liquid (that we know of)
Aside from Earth, Titan is the only world we know of that has liquids on its surface. These are in the form of lakes and rivers composed of liquid hydrocarbons including Ontario Lacus, a lake 240 kilometer (150 mile) long in Titan’s southern hemisphere.
- It has a climate system like Earth
The liquids on Titan undergo a similar cycle to water here on Earth. Liquid methane evaporates from the surface, forming extremely thick clouds in the skies, before eventually raining down and replenishing the lakes and rivers on the ground.
- We’ve landed on it, and we will again
The Saturn-orbiting spacecraft Cassini carried with it the Huygens probe, which landed on Titan (our only landing in the outer Solar System) on 14 January 2005. There are proposals being discussed for another landing, this time possibly using a boat.
References: Space Fact