Darth Vader's old gaff awaits exogorth desert DUNE DOOM

Anakin Skywalker's home city Mos Espa, featured in Star Wars prequel The Phantom Menace, is about to be swallowed up by the desert.

The film set in the Sahara desert - situated near the namesake of Darth Vader's home world, the Tunisian city of Tataouine - will be soon buried by a crescent-shaped sand dune, or barchan. The dune appears to be poised to "eat" the city in this time-lapse gif of collated Google Earth images from Kotaku.com. Sand dunes move across Earth 10 times faster than the sands of Mars sweep across the Red Planet.

Real homes are rarely built in dune fields and the temporary Mos Espa set, built to depict part of the planet Tattooine, shows why. Boffins have used the buildings as a fixed point to monitor the progress of the barchans across Tunisian portions of the Sahara desert via satellite imagery, as well conducting site visits in 2009 and 2011.

The researchers have also had access to a rich source of pictures of the site from the thousands of Star Wars fans who visit the site each year via the nearby oasis town Tozeur.

"One of the challenges in measuring dune migration on Mars or Earth is that dunes often appear in vast sand seas where not only can it be difficult to tell one dune from another, but there may be no fixed reference point against which to measure the dune’s position," report author Ralph Lorenz of John Hopkins University wrote on a blog for The Planetary Society.

The barchan, the arc-shaped dune formed by wind blowing predominately in one direction, is estimated to be moving at a rate of 15 metres a year. The leading edge of the dune has already reached the first buildings on the outskirts of the popular tourist destination.

"In 2009, a large barchan dune loomed just east of the site," Lorenz wrote. "But even only a few years ago, this dune was nowhere near! The Google Earth historical imagery allows you to look at several images taken in previous years, and we measured the position of this dune and several others relative to the easily recognised buildings."

The current barchan looming over the site could still be stopped, but Lorenz reckons it would take quite an intervention to save Mos Espa.

"Even if the threatening barchan fizzles out as it meets the set, a larger, slower-moving barchan is lumbering behind it," he wrote.

However, the boffins said in their report that the importance of the site as a tourist attraction could see Tunisia intervene to try to save it.

"Given the importance of this site to the tourism industry of Tunisia, it may be that it is a candidate for mitigation measures, not being pursued at present," they said.

"These could include erecting fences or walls, bulldozing the approaching dune (which would take considerable effort and would have to be repeated with each oncoming dune), or moving the site out of the path of the dunes.

"There would be some irony in such measures being adopted to protect a science fiction film set: it was exposure to aeolian transport concerns and countermeasures that inspired author Frank Herbert to write a science fiction novel set on a desert world (the desert planet Arrakis in the classic sci-fi tome Dune) that itself became an epic film."

The full study, which was published in the journal Geomorphology, is available through the Lunar and Planetary Laboratory at the University of Arizona here (PDF). ®

* Exogorth - space slug, akin to the one from whose innards Han, Leia, Chewie and the 'droids escape in The Empire Strikes Back.