The NASA exhibit will be free and open to visitors Thursday and Friday on the National Mall in Washington.
The model of the next generation space telescope -- approximately 80 feet long, 40 feet wide and 40 feet tall -- is designed to give visitors a better understanding of the size, scale and complexity of the orbiting infrared observatory that is expected to be launched in 2013.
In addition, NASA will present exhibits involving its balloon program, the International Space Station, the Cassini Mission to Saturn, the Mars rovers and giant inflatable models of the space shuttle, the Orion crew exploration vehicle, and the Ares I rocket.
Public Service Recognition Week -- celebrated the first Monday through Sunday in May since 1985 -- is designed to honor those who serve as federal, state and local government employees.
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