Images from NASA's 2004 Cassini mission show river networks draining into lakes in north polar region of Saturn's largest natural satellite, Titan.

NASA/JPL/USGS

aturn's mysterious moon Titan has long intrigued scientists, but historically they've had a hard time studying the moon's terrain because it's surrounded by a thick orange haze. In 2004, NASA's unmanned Cassini spacecraft was finally able to penetrate Titan's murky fog, beaming geological images back to earth. Researchers from MIT and and the University of Tennessee at Knoxville who have been studying those images recently concluded that the moon's icy surface is surprisingly Earth-like in a number of ways. Here's what you should know:

What does Titan's surface look like?
It's remarkably crater-free, suggesting that the moon's outermost layer is constantly reshaping itself, just like Earth. Titan's landscape also boasts a number of swirling rivers that flow into giant lakes, mirroring our planet's water systems. Key difference: Titan's rivers are full of liquid methane, not water.

Are there other differences?
For the most part, Titan's rivers don't flow with the same force as most rivers on Earth. Rather, they trickle slowly through Titan's dense ice, in thinner, tree branch-like networks. They're "more on the long and spindly side," says MIT graduate student Benjamin Black, kind of like the winding rivers flowing through the volcanic terrain on the Hawaiian island of Kauai. 

How, specifically, has Titan's surface been reshaping itself?
While most moons in the solar system are dented all over with craters, Titan's surface is relatively smooth, the result, scientists theorize, of geological changes similar to ones that have happened on our planet. On Earth, for example, craters are a rarity because "plate tectonics, erupting volcanoes, advancing glaciers, and river networks have all reshaped Earth's surface over billions of years," says the Daily Galaxy. On Titan, similar processes — like icy lava eruptions, erosion, and sedimentation — are constantly reshaping it.

Source: Daily Galaxy, Daily Mail, Science Daily, Space.com