�鶹������ҳ���

Could a moon near Saturn be the most Earth-like planet out there?

That's what scientists from Nasa are looking into, as they study Saturn's largest moon - Titan. They're trying to work out how its landscape formed.

They say that Titan has seasons, rains, rivers and even seas. But before you get too excited, it won't be water that is sloshing around, but liquid methane, and the gust winds will be nitrogen!

Planetary experts from the University of Stanford in California - alongside colleagues from Nasa - are studying Titan's landscape closely - as it's seen as a potential place for humans to set up a future base.

Using information from the Cassini mission, the team have been working on a project to understand how seasonal changes could have shaped a very Earth-like structure of mountains, ice, sand dunes and wide plains rather than just a windy dusty desert.

On Earth, rocks and minerals get eroded by water and end up moving around the planet as tiny grains. They are moved by winds and rivers to new places where they settle and turn back into rocks.

Those rocks then continue forming, being eroded, and reforming, over millions of years to form the landscapes we all see.

Experts think the same thing could be happening on Titan - just with very different minerals.

Mathieu Lapôtre, from Stanford's School of Earth, Energy & Environmental Sciences said: "Our model adds a unifying framework that allows us to understand how all of these sedimentary environments work together.

"If we understand how the different pieces of the puzzle fit together.... then we can start using the landforms left behind... to say something about the climate or the geological history of Titan - and how they could impact the prospect for life on Titan."