Thierry Legault, an engineer and amateur astronomer, is famous for his striking photographs of space, like this image of the International Space Station silhouetted against the sun. He has also captured distant galaxies, the rings of Saturn, and even moonbows here on Earth. 

Thierry Legault

Motherboard caught up with him recently to ask him about another facet of his stargazing hobby -- tracking satellites as they orbit the Earth. Working with a fellow astronomy buff, Emmanuel Rietsch, he combined his telescope setup with Rietsch's custom software to track objects across the sky automatically. Discovering and photographing these spacecraft overhead is especially fun, he explains, when the flying objects in question are classified intelligence satellites. 

“We know their trajectory, their orbital data, and we take images with some details,” he tells Motherboard (read the full article here), "but we can’t discover really the capabilities of these satellites. So it’s more like a game: spying spy satellites.” Check out the short documentary below, produced by Erin Lee Carr and Chris O'Coin for Motherboard, and browse more of Legault's photographs on his site.  

For more videos from Motherboard, visit http://motherboard.vice.com/.