S121-E-07708 (15 July 2006) --- Astronaut Piers J. Sellers, STS-121 mission specialist, and cosmonaut Pavel V. Vinogradov, Expedition 13 commander representing Russia's Federal Space Agency, bid farewell to one another prior to the undocking of the Space Shuttle Discovery and the International Space Station. European Space Agency (ESA) astronaut Thomas Reiter (left) and astronaut Mark E. Kelly (background), STS-121 pilot, are also pictured.