Physicist Brian Cox serves as the moderator for a panel discussion with Apollo astronauts during the Apollo 11 50th Gala on July 16, 2019. The gala, presented by Northrop Grumman, was held inside the Apollo/Saturn V Center at the Kennedy Space Center Visitor Complex. From left, are Apollo 9 astronaut Rusty Schweichart, Apollo 11 astronaut Michael Collins, Apollo 16 astronaut Charlie Duke, and Apollo Flight Director Gerry Griffin.

Retired NASA astronauts participate in a panel discussion during the Apollo 11 50th Gala, presented by Northrop Grumman, on July 16, 2019. The gala was held inside the Apollo/Saturn V Center at the Kennedy Space Center Visitor Complex in Florida. From left, are Apollo 11 astronaut Michael Collins, Apollo 16 astronaut Charlie Duke, and Apollo Flight Director Gerry Griffin.

A panel discussion with Apollo astronauts took place during the Apollo 11 50th Gala, present by Northop Grumman, inside the Apollo/Saturn V Center at the Kennedy Space Center Visitor Complex in Florida on July 16, 2019. From left, are Apollo 9 astronaut Rusty Schweickart, Apollo 11 astronaut Michael Collins, Apollo 16 astronaut Charlie Duke, and Apollo Flight Director Gerry Griffin.

Gerry Griffin, Apollo flight director, makes remarks during the Apollo 11 50th Gala, pressented by Northrop Grumman, inside the Apollo/Saturn V Center at the Kennedy Space Center Visitor Complex on July 16, 2019

Gerry Griffin, Apollo flight director, left, presents the Pioneer Award to JoAnn Morgan, retired NASA engineer, during the Apollo 11 50th Gala, on July 16, 2019. The gala, presented by Northrop Grumman, was held inside the Apollo/Saturn V Center at the Kennedy Space Center Visitor Comples in Florida. Morgan was the first woman engineer on console at Kennedy Space Center and the only woman in the firing room during the Apollo 11 launch countdown and launch.

CAPE CANAVERAL, Fla. -- The Apollo/Saturn V Center at NASA's Kennedy Space Center in Florida hosted a celebration on the 40th anniversary of NASA's Apollo 15 mission. An elite gathering of Apollo-era astronauts were on hand for the event and panel discussion. Gerry Griffin, Apollo 15 flight director moderates the question-and-answer period with the panel. From left are: Apollo 15 astronaut backup support crew members, Joe Allen, Jack Schmitt, Vance Brand and Dick Gordon; Al Worden and Dave Scott. Worden circled the moon while Scott and the late Jim Irwin, the Lunar Module commander, made history when they became the first humans to drive a vehicle on the surface of the moon. They also provided extensive descriptions and photographic documentation of geologic features in the vicinity of the Hadley Rille landing site during their three days on the lunar surface. Photo credit: NASA/Kim Shiflett

CAPE CANAVERAL, Fla. -- The Apollo/Saturn V Center at NASA's Kennedy Space Center in Florida hosted a celebration on the 40th anniversary of NASA's Apollo 15 mission. Apollo 15 Commander Dave Scott and Command Module Pilot Al Worden and an elite gathering of Apollo-era astronauts were on hand for the event and panel discussion. Here, Gerry Griffin, Apollo 15 flight director, speaks to the invited guests. Worden circled the moon while Scott and the late Jim Irwin, the Lunar Module commander, made history when they became the first humans to drive a vehicle on the surface of the moon. They also provided extensive descriptions and photographic documentation of geologic features in the vicinity of the Hadley Rille landing site during their three days on the lunar surface. Photo credit: NASA/Kim Shiflett