JSC2011-E-028160 (23 March 2011) --- NASA astronauts Greg H. Johnson (right), STS-134 pilot; and Greg Chamitoff, mission specialist, are pictured during an exercise in the systems engineering simulator in the Avionics Systems Laboratory at NASA's Johnson Space Center. Photo credit: NASA or National Aeronautics and Space Administration
Photographer DAVID DeHOYOS
Date March 23, 2011