Honor guards march to the Astronaut Memorial Mirror at NASA's Kennedy Space Center Visitor Complex to participate in a U.S. Honor Flag ceremony.

Honor guards march to the Astronaut Memorial Mirror at NASA's Kennedy Space Center Visitor Complex to participate in a U.S. Honor Flag presentation ceremony.

The flag is presented to NASA to be prepared to fly aboard space shuttle Atlantis on the Space Shuttle Program's final mission, STS-135. The U.S. Honor Flag has been flown nationwide, at Ground Zero and throughout the world to honor heroes who have lost their lives while serving their community and country, including police officers, firefighters, members of the Armed Forces and astronauts. More than 100 honor guard members traveled to the Space Coast to take part in the ceremony. After the flag returns to Earth, it will continue as a traveling memorial. Photo credit: NASA/Troy Cryder