Space Shuttle Discovery
Credit: Getty Images
ARLINGTON, VA - APRIL 17: The space shuttle Discovery rides atop a Boeing 747 as it flies past Washington, on April 17, 2012 in Arlington, Virginia. The retired shuttle was traveling to the Smithsonian's Air and Space Museum's Udvar-Hazy Center in Chantilly, Virginia, where is will go on display. This photograph was taken at the Top of the Town in Arlington, Virginia.
(Photo by Mark Wilson/Getty Images)