Shooting lasers down from planes to pierce the thick foliage and paint a 3-D picture of the ground below.

Jacey Fortin reports at The New York Times,

They were hidden there, all this time, under the cover of tree canopies in the jungles of northern Guatemala: tens of thousands of structures built by the Maya over a millennium ago.

Not far from the sites tourists already know, like the towering temples of the ancient city of Tikal, laser technology has uncovered about 60,000 homes, palaces, tombs and even highways in the humid lowlands.

...Researchers found the structures by shooting lasers down from planes to pierce the thick foliage and paint a 3-D picture of the ground below. The technology is called Light Detection and Ranging, or lidar.

...“This world, which was lost to this jungle, is all of a sudden revealed in the data,” said Albert Yu-Min Lin, an engineer and National Geographic explorer who worked on the television special. “And what you thought was this massively understood, studied civilization is all of a sudden brand new again.”

The lasers are only the first step, he added, noting that he and archaeologists still had to trek through jungles to verify the data while contending with thick undergrowth, poisonous snakes, swarms of killer bees and the odd scorpion.

...“I don’t think you see a lot of discoveries happening across the sciences right now that sort of turn a discipline on its head,” he said. “It’s exciting to know that it can still happen.”

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