Adam makes a replica of one of NASA's classic lunar experiments: a laser ranging retroreflector left on the Moon that are used for precise measurement of the orbit and orientation of the Moon relative to Earth. It's a model that makes use of off-the-shelf prisms that mirrors light directly back to its point source, like the mirrors on road markers or bicycles. This replica is of the kind of retroreflector array NASA is sending with current Mars missions. And for this quick build, we see the debut of some tools like the sheet metal nibbler and unibit!