TIME SCANNERS: MACHU PICCHU
PBS, 10:00 p.m. ET
This series uses some very modern technology – in this case, 3D laser scanning – to probe some very ancient wonders. In tonight’s new episode, structural engineer Steve Burrows and host Dallas Campbell try to figure out how the Incan city of Machu Picchu was constructed, and why. One of the things they learned had to do with where all the bodily wastes went – and their discovery, you might say, uncovers a veritable royal flush. Check local listings.