Participants in this category must also write a technical paper explaining how their design takes advantage of NASA's ideas and potentially improves on them.
This category divides entrants into young student builders ages 13 to 18, and an open group for anyone age 13 and older. Two winners, one for each group, will be awarded a custom LEGO trophy.
The "Imagine our Future Beyond Earth" challenge asks participants 16 and older to design and build a futuristic air, space, or land vehicle with LEGOs.
Designs, including rotorcraft, rockets, rovers and more, can be based in reality or purely imagined. The grand prize is a LEGO set signed by the set's designer and a collection of NASA memorabilia.
The "NASA's Missions: Imagine and Build" competition opens Wednesday with an entry deadline of July 31. Complete rules for design and paper submission are available at LEGO's ReBrick site.
Winners in each category will be selected by a panel of NASA and LEGO officials and announced September 1.