The Parkes radio telescope in New South Wales, Australia, is one of the most elegant scientific instruments ever built. Pointed to the heavens, its giant white parabolic dish – mounted on a brick tower like a windmill – glints under clear blue skies in the early morning sunshine. The ‘dish’ sits in a natural bowl of lush farmland, an hour’s flight west of Sydney, surrounded by wooded hills.  But its idyllic setting does have a few drawbacks. “We have three of the five deadliest snakes in the world on site,” warns Parkes’ operations scientist John Sarkissian, as we walk across the grass to the entrance. “You learn to live with them – stomp your feet and speak loudly, they’ll just slink away.”  The Parkes observatory began operating in 1961. Since then it has helped transform our view of the Universe. “The telescope is used to detect radio emissions from the stars,” says Sarkissian. “For millennia most of the Universe was hidden to us but, with the development of technology, new areas of the magnetic spectrum have opened up.”  The 64-metre-wide telescope has been used to map the structure of galaxies, discover pulsars – rapidly spinning dead stars, uncover black holes and track deep space missions. However, it is best known for relaying to Earth live TV pictures of Neil Armstrong and Buzz Aldrin’s first footsteps on the Moon on 21 July (Australian time) 1969.  The events of the day are immortalised in the 2000 film The Dish where we see engineers battling severe weather, power failures and personality clashes to ensure the world witnesses history being made.  Away from the electronic equipment racks of the control room, most of the original technology remains  Disappointingly, the original ‘60s control panel originally used to steer the telescope has been replaced by a computer. “We did have a console that resembled something out of Thunderbirds,” says Sarkissian, “with dials and globes, it looked really cool.”  Nevertheless, away from the electronic equipment racks of the control room, most of the original technology remains. Sarkissian checks the dish is locked pointing straight upwards towards the sky (the stowed position) before we clamber outside onto the circular walkway at the top of the supporting tower. Above us are the heavy-duty motors, greasy wheels and gears of the tilting mechanism.  A flight of stairs, two narrow ladders and a fright involving a trapped bird later and we are on an open gangway directly beneath the dish. With the ground six storeys below and the wind picking up, it feels horribly exposed.  “You can think of the dish as a glorified beach umbrella,” says Sarkissian. “Even when there’s a light wind blowing, it puts a lot of pressure on the dish surface so we have to be careful.”  In summer, high winds are common in this part of Australia. In winter, when the first Moon landing was scheduled, the breeze is usually light. But not when Apollo 11 touched down on the lunar surface. “They prepared for every contingency,” says Sarkissian, “even hand-cranking the dish to track the Moon in case they lost power.”  “Then just minutes before the moonwalk was due to begin, a violent squall hit the telescope with winds well over the safe operating speeds,” he says. They were, at the time, the highest winds ever recorded at Parkes. “When it was fully tipped over waiting for the Moon to rise, two sharp 110 km/h (68mph) gusts hit the dish and caused it to slam back against its pinions.”  Neil ‘Fox’ Mason was at the controls. “It shook the hell out of the dish,” he tells me when we sit down later over a coffee. “There were alarm bells going off, you could hardly hear yourself.”  Houston was switching between the signals but when they switched to Parkes, the signal was so good they stayed with it after that - John Sarkissian, operations scientist  With the circuit breakers removed from the alarms, director of the  observatory John Bolton held his nerve. “Everybody’s panicking – my instinct was to stow the dish,” recalls Mason, now in his 80s, “but I was told to carry on.”  “Just as Buzz Aldrin switched on the TV camera on the lunar module, the Moon moved into the field of view,” says Sarkissian. “The astronauts were on the Sea of Tranquillity on the Moon but it was the Ocean of Storms here.”  Parkes was one of three telescopes receiving telemetry and TV pictures from the lunar surface. “Houston was switching between the signals but when they switched to Parkes, the signal was so good they stayed with it after that,” says Sarkissian. “With a global audience of 600 million, it’s one of those few turning points in history watched by all mankind.”  But not quite all mankind. “Fox was the only man who didn’t see anything that was happening,” says engineer David Cooke, who was also in the control room that day and did get to see the live shadowy picture on a 16-inch (40cm) monitor. “Fox was told to keep watching the dials and don’t look anywhere else.”  “The pictures were coming in behind me, I could hear everyone else saying how amazing they were,” adds Mason.  “I remember one American operator who had worked on a lot of missions,” says Cooke, “and he just stood and looked at the picture and said ‘how about that’ – it was quite amazing.”  I do my best to mask my fear as I begin the climb, trying not to look down, my sweaty hands slipping on the low handrail  “When the TV transmission was over,” says Cooke, “I walked outside and there was the Moon and I thought, wow there are men up there.” He then took a picture of the Moon. Coincidentally, at the same time, Buzz Aldrin was taking a picture of Earth from the Moon.  Mason was only able to see a recording of the landing when he watched it on the evening news. “There are still people in Parkes that don’t believe it happened,” he says, “[they claim] it was all done in Hollywood.”  Back in the present day, I am right underneath the dish and starting to get a little anxious.  “We’re just going to walk along the walkway here,” Sarkissian says, setting off towards the outer rim of the dish. “It’ll get progressively steeper – and we’re going to pop out onto the surface.” I do my best to mask my fear as I begin the climb, trying not to look down, my sweaty hands slipping on the low handrail.  And then we are in the dish and the vertigo vanishes. I am standing at the edge of a vast white bowl. The sides of the parabola get shallower as we make our way down towards the centre. Our view of the ground is lost, all we can see are the walls of the dish and, above us, three pylons rising 26m (85ft), like a giant tripod, to the white hexagonal telescope detector high above us. The dish is merely the collector of signals – the detector is the focus of the telescope.  “You can think of it like a giant radio mirror,” says Sarkissian. “The surface area here is about an acre.”  The film’s producer thought he’d get people to stand in it and do something, well that’s boring, so he made them play cricket – John Sarkissian  I feel very small. And with the blazing Sun reflected off the curved surface around me, very hot. Then I notice some unexpected markings on the low pillar at the centre of the dish: cricket stumps.  “In the film, they always say it’s a big dish but very few people have stood on the dish, so how big is big?” says Sarkissian. “The film’s producer thought he’d get people to stand in it and do something, well that’s boring, so he made them play cricket – it’s both humorous and it gives people an idea how big it is – if you can play cricket on it, it must be big.”  Sadly, no-one actually played cricket on the dish in 1969. It was a sackable offence apparently. Sarkissian taped on the current stumps to commemorate the 40th anniversary of the landings.  We descend from the dish through a small circular hatch, down a series of metal ladders to eventually emerge from a door at the centre of the control room. With the equipment upgraded for a new series of observations, the dish is unlikely to be retired any time soon.  “When I was a schoolboy on the cover of my maths text book was a picture of the Parkes telescope and I used to dream about working here one day,” says Sarkissian. “You have to pinch yourself – this is a fantastic place to work, it’s a beautiful radio telescope and it generates wonder in people.”  Join 700,000+ Future fans by liking us on Facebook, or follow us on Twitter, Google+, LinkedIn and Instagram  If you liked this story, sign up for the weekly bbc.com features newsletter, called “If You Only Read 6 Things This Week”. A handpicked selection of stories from BBC Future, Earth, Culture, Capital, Travel and Autos, delivered to your inbox every Friday.
In a quiet corner of rural Australia sits a giant radio dish that helped ensure the most famous space mission of all could be seen on TV. Richard Hollingham went to visit it.