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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