Hello, friends! Welcome to Our Place in Space: A to Z! For this year’s A to Z Challenge, I’ll be taking you on a partly imaginative and highly optimistic tour of humanity’s future in outer space. If you don’t know what the A to Z Challenge is, click here to learn more. In today’s post, X is for…
`Titan is the largest moon of Saturn. It’s a very cold place. It’s so cold on Titan that water is basically a kind of rock, and certain chemicals that we typically think of as gases (i.e.: methane and ethane) flow freely as liquids. As a result, the surface of Titan looks surprisingly similar to some regions on Earth: a rocky landscape eroded by rain and rivers. Except the “rock” is frozen water, and the rain and rivers are a mix of liquified methane and ethane. One of the most curiously familiar “rock” formations on Titan lies near the equator. It’s called Xanadu.
Xanadu is an Australia-sized region of craggy hills and mountains. Due to Titan’s thick, hazy atmosphere, it’s impossible to see Xanadu (or any other surface feature on Titan) except in certain specific wavelengths, such as certain wavelengths of infrared. When Xanadu is visible, it appears as a bright splotch on Titan’s surface, surrounded by much darker desert terrain.
It’s unclear how Xanadu came to be. One hypothesis I read argues that Xanadu could be associated with some sort of giant impact event. Perhaps a large asteroid or comet smashed into Titan, disrupting the icy crust, which then refroze as this jagged and craggy terrain. Another hypothesis suggests that Xanadu was created by some sort of tectonic activity—a fascinating possibility. At this point, Earth is the only world confirmed to have plate tectonics.
In this Our Place in Space series, I’ve tried to emphasize all the cool and exciting things humans could do in the distant future. I have also mentioned, from time to time, my belief that humans in the distant future will learn to be good stewards of the Earth. Space exploration can help us do that. Titan is so curiously familiar, yet also so weirdly different from Earth. Trying to understand why Titan is so different-yet-similar can teach us much about our own world—which, in turn, will help us figure out how to take better care of our planet.
But there’s a catch. Just as we have a responsibility to take better care of Earth, we also have a moral responsibility to not mess up Titan. Remember Titan’s thick, hazy atmosphere? There are some weird chemicals forming in that atmosphere. Organic chemicals. Could those organic chemicals be associated, in one way or another, with biological activity? Maybe. Maybe not. No one can say at this point.
In the next few years, NASA will be sending a robotic helicopter to explore Titan’s Shangri-La region, one of the dark-colored regions directly adjacent to Xanadu. If we’re lucky, maybe that robo-helicopter will venture into Xanadu at some point. I have confidence that NASA will thoroughly sterilize all of their equipment before sending it to Titan to ensure that we do not contaminate Titan with our Earth germs.
There will be many more missions to Titan in the future. Just as Mars is crawling with Mars rovers today, Titan will be covered in Titan rovers, Titan helicopters, and Titan submarines in the future. The place has too much in common with Earth, and we simply cannot leave it unexplored. But humans in the distant future will not only be good stewards of the Earth; they’ll be good stewards of the Solar System. And so, whether we’re exploring Xanadu or Kraken Mare or Shangri-La, or any other region on Titan that has a super cool name, strict safety precautions will always be a must.
Want to Learn More?
I had a really hard time finding information about Xanadu for this post. I’m guessing that’s because very little information is available at this time. More exploring needs to be done! What I did find came from these three scientific papers: