rocket rat
n.— «It is an unforgiving hobby, but it is arguably safer for participants than in the past. Like many of the Black Rock “rocket rats”—largely men of a certain age—Mike Mullane, 61, a retired space shuttle astronaut, recalled his boyhood rocketry experiments with black powder and other dangerous substances.» —“A Cult of Backyard Rocketeers Keeps the Solid Fuel Burning” by Patricia Leigh Brown in Gerlach, Nevada New York Times Oct. 14, 2006. (source: Double-Tongued Dictionary)