Buzz Aldrin , one of the first two men to walk on the moon , used one of the world 's oldest monuments to send a message about the future of space exploration . The 85-year-old former NASA astronaut , who touched down on the moon in 1969 with Neil Armstrong , posted a picture on Twitter of himself in front of England 's Stonehenge , wearing a T-shirt reading , 'Get your a** to Mars ' . 'While at @ EH_Stonehenge yesterday I decided to send a message to the cosmos , ' he wrote on Tuesday , accompanying the photo . Buzz Aldrin posed in front of Stonehenge in a T-shirt reading , 'Get your a** to Mars ' on Monday , claiming he was sending ' a message to the cosmos ' Stonehenge , a prehistoric ring of standing stones , dates back to between 3,000 and 2,000 BC . Aldrin 's picture is the last move in his campaign for the U.S. to focus on having human settlement on Mars . The veteran astronaut has written a series of columns stressing that space exploration should continue . Aldrin has stressed numerous times over the years that space exploration needs to continue and the U.S. needs to have a goal of settling on Mars . He wrote in CNN last year : 'The moment to begin could be on the occasion of the 50th anniversary of Apollo 11 's touchdown on the moon . 'We can make a courageous , Kennedyesque commitment to America 's future in deep space . 'The U.S. President could utter these momentous words : `` I believe this nation should commit itself , within two decades , to commencing an America-led , permanent presence on the planet Mars . '' ' In November of last year , he wrote a column for TIME , stressing that more people need to touch down in space . He wrote : ' I firmly believe we will establish permanence on that planet . And in reaching for that goal , we can cultivate commercial development of the moon , the asteroid belt , the Red Planet itself and beyond… . 'We need to look forward to countries around the globe following our lead and establishing a rotating permanence on Mars for science and commercial resources . 'Some 45 years ago , when Neil Armstrong and I stepped upon the surface of the moon at Tranquility Base , we fulfilled a dream held by humankind for centuries . 'Yes , it was one small step . Today , more steps are needed. ” . Aldrin holds his doctorate in astronautics and has consulted for the U.S. government on the future of space exploration .
Aldrin is one of the first two men to walk on the moon in 1969 . While standing in front of Stonehenge , he posed in a shirt that read , 'Get your a** to Mars ' The veteran NASA astronaut has written a series of columns stressing the importance of space exploration .