User blog comment:Mrob27/The moat experiment/@comment-69.11.30.207-20120411164842/@comment-4583259-20120413231822

Yep, that's the idea. Dig a big long trench, then every now and then you can just walk the length of the trench and deal with any astronauts you find. I also used a more open-pit approach:



and got a boatload of astros:



but the narrow trench is a lot faster to dig.