If you build your home in the middle of a dune field, you're gonna have a bad time. Consider the buildings of Mos Espa (the Tatooinian city featured in The Phantom Menace), which are about to be buried by a hill of sand advancing steadily across the Tunisian desert.
The Star Wars set, scientists predict, will soon be overtaken by the dune. That's a bummer for Mos Espa (the sands reportedly made contact this year, and are now encroaching on Qui-Gon Alley), but great news for Ralph D. Lorenz, a planetary scientist at Johns Jopkins University.
For one thing, the set's buildings provide a fixed geographic reference point – a helpful feature when measuring the migration of sand dunes with satellite imagery. The set's cultural relevance has also made the dunes easier to monitor from the ground. Its "popularity as a destination for Star Wars enthusiasts," write the researchers in the latest issue of the journal Geomorphology, "results in many photographs being posted on the Internet, providing a rich set of in-situ imagery for continued monitoring in the absence of dedicated field visits."
Lorenz and his team have therefore been able to monitor the movement and distribution of wind-blown, crescent-shaped dunes called "barchans." Barchans, which form when sand swept up the windward side of a dune crests the peak and cascades down the leeward side, have been observed throughout the solar system, including on the surface of Mars:
Images like these help geologists and planetary scientists understand wind's role in shaping a planet's surface over time, through what are called aeolian processes. The dunes about to overtake Mos Espa, for example, have been clocked advancing at a pace of around 15 meters per year, and are thought to transport some 50 cubic meters of sand per meter per year. Understanding the wind's geological impact, and recognizing how that impact varies not just here on Earth, but other places in our solar system, can teach us much about a planet's geological and climatological past, present, and future.