Water is essential for existence and existence of lives in other worlds so far are fictional. But are there rivers and lakes on other worlds? The answer is yes but the water is not made of combination of hydrogen and oxygen. Titan which is the largest moon of Saturn has lakes and streams on titan and are made of methane and ethane. The methane can move back and forth between the surfaces of atmosphere.
This means we don’t just have lakes and streams and rivers. We also have rain and clouds and on Titan is might be possible to see a rainbow. At other points in solar system history we do think other worlds also had lakes and streams in its surface earlier in history.
So there are two points in solar system history we do think other worlds also had lakes and streams. For example on Mars had a hot liquid water on its surface earlier in its history. And there is more to be discovered in distant galaxies and planets as we stare to learn about planets around other stars.
