As you pass the “turn off all phones” sign and set off on the 4-kilometre drive to CSIRO’s Canberra Deep Space Communication Complex (CDSCC) at Tidbinbilla, the first thing that catches your eye is the radio telescope looming above the rolling green fields.

Deep Space Station 43, whose mighty dish is 70 metres in diameter, is the largest steerable radio antenna in the southern hemisphere. With support from the other CDSCC dishes, it is Earth’s sole link with far-off probes like Voyager 2, situated at the edge of the solar system, and New Horizons, which photographed Pluto and is now deep in the Kuiper Belt. DSS-43 was also the telescope that picked up the final transmission from the Cassini probe as it vaporised in the atmosphere of Saturn in September.

It’s therefore easy to miss the much smaller telescope near the car park, its 26-metre dish pointed permanently at the sky. This is DSS-46, decommissioned in 2009 after 43 years of service. Originally it was installed at the Honeysuckle Creek tracking station, just under 40 kilometres away and long since closed. And, though few are aware of it, this telescope is how we received the first images of man setting foot on the Moon.

Ask an Australian about Apollo 11 and chances are they’ll rave about the key role that the Parkes radio telescope in central New South Wales played in relaying the first images of Neil Armstrong’s descent to the lunar surface. It’s the plot of 2000’s heartwarming dramedy The Dish, in which a ragtag team of local scientists lock horns with the stuffed shirts of NASA on the way to successfully receiving the first images from the Moon landing. It’s entertaining, inspiring, and not at all how it actually happened.

Characters were created, naturally, and plot elements added. But perhaps most notably, Parkes didn’t actually send those iconic images: it was DSS-46 at Honeysuckle Creek.

“Certainly Parkes played a role,” explains Glen Nagle, who holds the twin roles of outreach and administration lead and NASA operations support officer at CDSCC.

Originally Australia wasn’t scheduled to be anything but a back-up for Apollo 11. Ultimately it was only brought in because someone in California forgot to flip a switch.

“NASA’s original plan was to bring back the first images through their dish at Goldstone station: you know, use an American dish to show Americans walking on the Moon and beating the Soviets and winning the space race,” Nagle begins. “But when Goldstone received the signals from the Moon they had to relay them to Houston, Texas, and an incorrect switch setting at Goldstone meant that the picture received at Houston of Neil Armstrong about to walk on the Moon was upside down.”

The picture was upside down because the camera was upside down: a deliberate choice to make the handle easier to grasp with thick, insulated gloves. The idea was that the images of the historic moment when the astronauts climbed down the ladder would be captured by the upside-down camera fixed to the lander and flipped at Goldstone. Once Armstrong and Buzz Aldrin were on the surface they would move the camera to a tripod.

The picture being upside down was embarrassing, but swiftly amended. However, that was only the beginning of a series of problems.

“The picture they were receiving at Houston was degrading along the way: blacks were very black, the whites were very white, and you couldn’t make out what was happening,” Nagle continues. “So Neil’s coming down the ladder and Houston wanted to find a better picture, and fast.”

Parkes had been chosen to collect the images sent from Apollo 11, but that was thrown off because Armstrong and Aldrin had changed their schedule.

“They’d been told to first land safely on the surface of the Moon. Second, get the spacecraft ready for relaunch in case of emergency. And third, go through a six- to eight-hour eat-and-sleep period so they’d be rested before they walked on the lunar surface. And they basically said, ‘Well, hey: we’ve just landed on the Moon, pretty excited, can’t sleep, want to start exploring as soon as possible.’”

The astronauts left the module three and a half hours earlier than expected. “What that meant for Parkes was that the Moon hadn’t risen in their local sky yet. They had to wait about ten minutes for the Moon to get in their dish’s beam path to get a good signal. And Neil wasn’t going to just hang on the ladder waiting for that to happen.”

The Moon had risen high enough for the station at Tidbinbilla, which would normally have taken over. Except there was another issue.

Twenty-four hours earlier, a fire had damaged Tidbinbilla’s electrical system. Although technicians worked around the clock to return the antenna to working order, NASA had already swapped to its back-up plan. “So Neil’s coming down the ladder. NASA looks to Goldstone: upside-down picture, highly contrasted, no good. Parkes: no picture at all … That left Honeysuckle Creek.”

The station there, the smallest of all the Apollo mission telescopes, was only meant to get voice and data transmissions from the lunar module. “But on that afternoon they were also carrying the TV signal. And they had a great picture. So NASA flicked the switch just in time, and 600 million people around the world could witness Neil Armstrong coming down the ladder, putting his left foot on the Moon and saying those immortal words: ‘That’s one small step for man, one giant leap for mankind.’”

After about eight minutes, the Moon was high enough for the more powerful Parkes telescope to take over.

“[The Dish] doesn’t depict all that back and forth. And obviously it couldn’t: it’d be five hours long with a cast of hundreds,” Nagle says with a laugh. “And it’s a great film, and it made people remember that Australia plays a role in these missions.”

There’s a tangible artefact at the CDSCC visitor centre: a 13-gram piece of moon rock (volcanic basalt), donated by NASA in 1994 in gratitude for Australia’s participation in the Apollo missions. If you were hoping that this physical evidence, not to mention the remarkable story of DSS-46, would convince Moon landing sceptics that Apollo was not filmed on a Hollywood sound stage … “We get them all the time!” Nagle sighs. “We constantly get visits from people who don’t believe we landed on the Moon. And it begs the question, ‘Then why are you here?’”

CDSCC, in the wake of the Cassini mission, has plenty to get on with. For one thing, it’s still the premier site for communicating with the 35 space missions currently operating.

“It’s only going to get busier,” Nagle explains. “Now Juno [Jupiter orbiter] is the main mission, and it’s likely to get a extension; we’ve got the Martian seismological study InSight launching; we’ve got the James Webb Space Telescope heading on out there; and we’re gearing up for Exploration Mission-1, the space launch system that will eventually take humans to the Moon and Mars – and next year is the Solar Probe Plus launch.”

Then, in 2020–21, “we’ll have five, maybe six missions arriving at Mars all within a one- or two-month period: NASA, the Europeans, the United Arab Emirates, Japan, possibly India and possibly [Elon Musk’s] SpaceX as well”.

So CDSCC will have a lot of priority-juggling ahead? “Yes, but we’re good at what we do.”