This United States one dollar bill holds the signatures of the three Apollo 16 astronauts (John Young, Ken Mattingly, and Charlie Duke) in addition to two other signatures, that of a certifying official from the National Aeronautic Association and one from a NASA official, all on the front of the bill. This memento of the fifth human landing on the Moon in April 1972 was part of the official process of certifying the flight.
Before human spaceflights, the NAA had the astronauts autograph dollar bills, witnessed by an official from the NAA (and in this case also from NASA) who also signed the bills. The bills were then placed aboard the spacecraft. After the mission, recovering the identifiable bills served "as the basis for certification of the identity of the astronauts on each of the flights."
The NASA Johnson Space Center transferred this bill to the National Air and Space Museum in 1976.
Transferred from NASA - Johnson Space Center