To The Moon

Originally published in the Informanté newspaper on Thursday, 27 July, 2017.

Forty-eight years and one week ago, mankind first landed on the moon. This means that more than three-quarters of Namibia’s population was not yet born when this momentous occasion happened, and of those that were, a significant portion were either too young to remember it, or did not have the technological capability available in their homes to witness it. For those who missed it, this written account should hopefully suffice. 

The journey to the moon started a few days earlier, on 16 July 1969. At the Kennedy Space Center stood a Saturn V rocket – the largest ever constructed at that stage. At 13h32 UCT, its engines fired, and the journey started. After a mere twelve minutes, the craft entered orbit around the earth, at an altitude of 186 km. They orbited one and a half times before the third-stage rocket engine fired, and pushed the spacecraft onto its trajectory towards the moon. 

30 minutes later, the Apollo Command/Service Module separated from the rocket stage, and turned around. It docked with the rocket stage to retrieve the Lunar Module that was still attached to the rocket stage, and once that was done, adjusted its course to head for the moon, while the rocket stage continued on a trajectory past the moon and into orbit around the sun. 

Three days later, Apollo 11 passed the moon and fired its engines to enter orbit around the moon. Three days, and 384 000 kilometres later. A little known fact is that all other planets in the solar system can fit in between the Earth and the Moon – and our astronauts covered that distance in three days. The orbited thirty times, passing over their selected landing site in the Sea of Tranquillity while preparing for their descent. 

On July 20, 1969, Commander Neil A Armstrong and Lunar Module Pilot Edwin ‘Buzz’ E Aldrin, Jr, entered the Lunar Module ‘Eagle’, leaving Command Module Pilot Michael Collins along on the Command Module ‘Colombia.’ As the Eagle separated from the Columbia, it first pirouetted before Collins so he could ensure it was not damaged.

As their descent began, the crew of the Eagle saw that they were passing the surface about four seconds ahead of what was expected, and reported that they would land west of their target location. Five minutes into the descent, they found themselves with a problem. The Lunar Module navigation and guidance computer started reporting ‘1202 and ‘1201’ alarms. This computer was not a large one, with a Central Processing Unit running at about 1.024 Megahertz, or about 2000 times slower than a modern iPhone 7’s CPU, with core memory of about 4 kilobytes, or less than this entire article in plain text.

What had happened was that a radar switch was placed in the wrong position due to an error in the manual, and it was bombarding this small computer with signals it did not require. Its software, fortunately, was smart enough to realize this, and the alarms indicated that it was suspending non-essential tasks to focus on the important ones – the ones needed for landing. 

Computer Engineer Jack Garman realised this, and told guidance officer Steve Bales that it was safe to continue descent, and it was relayed to the crew. Armstrong looked outside, however, and saw that the computer’s landing target was filled with boulders, and at the edge of a crater. Armstrong took semi-automatic control, with Aldrin calling out data to allow him to control the descent. 

A few moments before landing, Aldrin noticed the light that indicated one of the 170 cm probes hanging from the Eagle had touched the surface, and he said, “Contact light!” Three seconds later, the Eagle landed, and Armstrong said, “Shutdown.” Aldrin followed this with, “Okay, engine stop. ACA – out of detent.” Armstrong acknowledged him with, “Out of detent. Auto.” Aldrin continued, “Mode control – both auto. Descent engine command override off. Engine arm – off. 413 is in.”

The Capsule Commander at NASA, Charles Duke, acknowledged their landing with, “We copy you down, Eagle.” Armstrong first acknowledged Aldrin’s checklist completion with, “Engine arm is off.” Then he responded to Duke with the message, “Houston, Tranquillity Base here. The Eagle has landed. “ 

Armstrong had unannounced and unplanned changed their call sign from Eagle to Tranquillity Base to emphasize that their landing was successful. Duke expressed his relief at this, and accidentally mispronounced the call sign as he responded, “Roger, Twan— Tranquillity, we copy you on the ground. You got a bunch of guys about to turn blue. We're breathing again. Thanks a lot.”

The mission now called for a five-hour sleep cycle for the astronauts, but they elected to continue preparations for their extra-vehicular activities, as they felt they would not be able to sleep. Preparation took longer than the two hours scheduled, but soon they were ready to begin. The highest heartrates recorded from the Apollo astronauts occurred with their egress from the Lunar Module.
Armstrong stood on the footpad of the lunar module and described the surface dust as very fine-grained, and almost like a powder, before, six and a half hours after landing, he stepped off the module and declared, “That’s one small step for a man, one giant leap for mankind.” 

After more than 21 and a half hours on the lunar surface, they started their journey back. They had left behind several scientific instrument that would continue sending data back, as well as an Apollo 1 mission patch and a memorial bag containing a gold replica of an olive branch, the traditional symbol of peace. But perhaps most memorable was the plaque left of the lunar descent stage, bearing drawing of both hemispheres of Earth, the signatures of the astronauts and President Richard M Nixon, and an inscription that read:

Here men from the planet Earth first set foot upon the Moon, July 1969 A.D. We came in peace for all mankind.

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