Happy to be at the #VeteransDayParade opening ceremony. #GodBlessAmerica pic.twitter.com/pWfsOGhmVkNovember 11, 2019

Generations of NASA astronauts in space and on Earth took a moment today (Nov. 11) to mark Veterans Day .

That's no surprise, since more than 60% of active astronauts have served in some branch of the military, according to NASA's Johnson Space Center , which oversees the astronaut corps. Those veterans include astronaut Andrew Morgan, who is currently living and working on the International Space Station during what will be a nine-month stay.

It’s a privilege to honor our nation's veterans today. My own family’s military service extends through multiple generations, representing every branch. I honor all vets by bringing reminders of my family's military legacy to space with me. Your service inspires me! #VeteransDay pic.twitter.com/d7e908yRo6November 11, 2019

"It's a privilege to honor our nation's veterans today," Morgan wrote on Twitter. "My own family's military service extends through multiple generations, representing every branch. I honor all vets by bringing reminders of my family's military legacy to space with me. Your service inspires me!"

Retired NASA astronaut Buzz Aldrin , who landed on the moon 50 years ago, also marked the day, joining in New York City's Veterans Day Parade. Before joining the astronaut corps, Aldrin attended West Point, served in the Air Force and flew combat missions during the Korean War.

"100 years of Veterans Day, 50 years of Apollo ; I'm proud to be a part of both," Aldrin wrote on Twitter before the parade began, later sharing photographs from the occasion. "God bless all that served this wonderful country."

The ceremony also fell on the 53rd anniversary of Aldrin's first launch to space, on Nov. 11, 1966. During that four-day-long flight, dubbed Gemini 12 , he and Jim Lovell, who later went on to fly in the Apollo 8 and Apollo 13 missions, concluded the Gemini program that prepared NASA for the moon-landing missions.

Email Meghan Bartels at mbartels@space.com or follow her @meghanbartels . Follow us on Twitter @Spacedotcom and on Facebook .