We’ve already given a general overview of the Apollo moon landings and the Apollo spacecraft, and we’ve talked about Apollo 7 to Apollo 10. Over the rest of our Apollo article series, we’ll be taking a closer look at each of the individual Apollo missions from Apollo 11, the first crewed moon landing, to Apollo 17, the last time to date that humanity set foot on the lunar surface.
As the first time humans walked on the moon, Apollo 11 is the Apollo mission you’ll hear most people talking about. In today’s post we’ll take a look at how Neil Armstrong and Buzz Aldrin made it to the moon’s surface, and at what stayed behind when they left.
The Apollo 11 crew and patch
You’ve probably already heard the names of Neil Armstrong and Buzz Aldrin, the first two people to walk on the moon. Armstrong was the commander and Aldrin was the lunar module pilot; you can read more about these roles in our post on the Apollo spacecraft.
Michael Collins isn’t as much of a household name, but he played an essential role in Apollo 11 as the command module pilot. While Armstrong and Aldrin went down to the lunar surface, Collins remained in the main body of the spacecraft, orbiting the moon alone, to help ensure they would be able to return safely.
Collins also designed the emblem for the mission patch, showing a bald eagle coming in to land on the moon. The emblems for previous crewed Apollo missions had included the names of the crew, but the Apollo 11 crew decided to leave their names off it, as they wanted the patch to represent all the many people who had made the moon landing possible.

The eagle on the patch is carrying an olive branch: a symbol of peace. Originally, it was planned to be carrying this branch in its beak. Due to concerns that the eagle’s extended talons looked too warlike, the design was changed so it was instead gripping the branch with its feet.
The lunar module for the Apollo 11 mission was named Eagle, leading to Armstrong’s famous phrase ‘The Eagle has landed’ when it touched down on the moon.
Apollo 11 launch, landing and global impact
Like all the Apollo missions from Apollo 8 onwards, Apollo 11 took off from NASA’s Kennedy Space Center in Florida. The launch took place on 16 July 1969, and a few days later Neil Armstrong became the first person to step onto the surface of the moon, at the landing site that he and Aldrin had named ‘Tranquility Base’.
The moon landing was a huge event, and the black-and-white live broadcast was watched by an estimated 650 million people around the world: close to a fifth of the global population at the time. If you were around in 1969, there’s a good chance you remember watching it. For the UK, Armstrong stepped onto the moon at around 4 am on 21 July, and BBC One stayed on air throughout the night to cover the event; it was the BBC’s first all-night broadcast.
If you’re interested in how the moon landing felt for the people on the ground, the Guardian has an interesting collection of accounts from members of the public.
What did Armstrong and Aldrin do on the moon?
Neil Armstrong and Buzz Aldrin spent 21 hours and 36 minutes on the moon, but most of that time was spent inside the lunar lander. They were actually on the moon’s surface, outside the lander, for about two and a half hours on a single excursion. After the crew of Apollo 11 had tested the waters, later Apollo astronauts would spend longer periods on the surface of the moon.
Like later Apollo astronauts, the Apollo 11 crew had undergone scientific training as well as training in how to operate the spacecraft. They’d been educated in various scientific fields, with a focus on geology, so they would be able to make meaningful scientific observations on the moon.
In NASA’s transcript of Armstrong and Aldrin stepping onto the surface, the astronauts report various details about the lunar surface and the physics of moving around on the moon:
Armstrong: The surface appears to be very, very fine grained, as you get close to it. It’s almost like a powder … I can kick it up loosely with my toe. It does adhere in fine layers, like powdered charcoal, to the sole and sides of my boots … There seems to be no difficulty in moving around – as we suspected. It’s even perhaps easier than the simulations of one-sixth [gravity] that we performed in the various simulations on the ground. It’s absolutely no trouble to walk around.
Aldrin: The mass of the backpack does have some effect in inertia … Traction seems quite good … You do have to be rather careful to keep track of where your centre of mass is. Sometimes, it takes about two or three paces to make sure you’ve got your feet underneath you.
Apollo 11 also gathered about 21 kg of lunar dust, soil and rocks to be returned to Earth for later study. Decades later, some of this soil would be used in experiments to determine whether it might be possible to grow plants on the moon.
While on the moon’s surface, Armstrong and Aldrin received a call from Richard Nixon, the US president at the time, to congratulate them on their achievement. ‘For one priceless moment in the whole history of man,’ the president said, ‘all the people on this Earth are truly one: one in their pride in what you have done, and one in our prayers that you will return safely to Earth.’
After their moonwalk, Armstrong and Aldrin tried to sleep in the lunar lander before leaving the moon. The original plan had been for them to sleep before stepping onto the surface instead, but they had asked permission to do the moonwalk first, as they were understandably excited to explore.
The astronauts struggled to sleep on the moon. The lunar lander was cramped, noisy, too cold and too bright, and there was nothing to use as a bed. NASA learnt from Armstrong and Aldrin’s uncomfortable experience, and later Apollo missions were equipped with blankets and hammocks.
What did Apollo 11 leave on the moon?
As mentioned, Apollo 11 collected some material from the moon’s surface, but it also left some things behind. Some of these were tools such as tongs, scoops and a hammer, discarded to save weight, but others were more significant.
The Apollo 11 crew placed several items on the moon to honour fellow spacefarers who had passed away, both from their own country and from overseas. Armstrong and Aldrin left behind an Apollo 1 patch, honouring Gus Grissom, Ed White and Roger Chaffee, the crew of Apollo 1, who were killed in a fire during a launch rehearsal. They also left two Soviet medals that had been awarded posthumously to the Russian cosmonauts Yuri Gagarin and Vladimir Komarov.
One item left on the moon was a coin-sized silicon disc inscribed with microscopic messages of goodwill from the leaders of 73 countries. You can read the messages over here.
The Apollo 11 crew installed a retroreflector on the moon: an array of mirrors, designed to reflect a beam of light back the way it came rather than at an angle. Similar retroreflectors were also left on the moon by Apollo 14 and Apollo 15.
The retroreflectors left behind by the Apollo missions are used to this day to measure the exact distance between the Earth and the moon, by bouncing laser pulses off the reflectors and calculating how long it takes the light to return to Earth. It’s not far off the way LiDAR works.
Perhaps most famously, Apollo 11 left behind an American flag, with a horizontal bar holding it up at the top to prevent it from drooping in the absence of wind. This flag was purely a symbolic gesture, rather than an attempt to claim the moon as US territory, as the 1967 Outer Space Treaty declares that nations cannot claim ownership of celestial bodies.

The flag wasn’t standing for long, though. Aldrin saw it being knocked over by the exhaust as the lunar lander took off. The flags planted by later Apollo missions were set down further from the lander.
Speaking of the lunar lander, the lower part of it remained on the moon. As we mentioned in our article on the Apollo spacecraft, the lunar module was divided into a lower descent stage and an upper ascent stage. When it was time for Armstrong and Aldrin to return to the main Apollo spacecraft, the ascent stage used the descent stage as a launchpad to take off, leaving the descent stage of the lander on the moon.
There’s also a plaque at the Apollo 11 landing site, attached to the descent stage of the lunar lander. Above the signatures of the three Apollo 11 crew members and President Nixon, the plaque reads:
Here men from the planet Earth
first set foot upon the moon
July 1969, AD
We came in peace for all mankind
Similar plaques were left to commemorate all the Apollo landings that followed.
To emphasise the message of peace, Neil Armstrong left behind a small olive branch symbol made of gold. You can see it in the below message from the NASA History Office’s Twitter account:
Perhaps most strikingly, Armstrong and Aldrin left behind their own footprints. With no wind or rain to disturb them, the footprints of the first people to walk on the moon are still there after five decades and will probably remain for a long time.
Images: NASA
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