First ever manned Moon landing!

Launch of the beautiful but terrifying Saturn V.

We have to remember the Moon on 21st July, 1969 – the date on which man first stood on the surface of an astronomical object other than the Earth. So 21st July 2009 is the 40th anniversary of that momentous event.

Those of us old enough to have been around at the time will never forget that day, but it all really started several days earlier. The Apollo 11 Saturn V launch vehicle lifted off from Pad 39A at the Kennedy Space Centre at 13:32 UT on Wednesday 16th July 1969. It took 12 minutes to reach Earth orbit. Then after one-and-half Earth orbits, the Saturn V’s third stage engine increased Apollo’s speed enough to escape the Earth’s gravity and start the real journey towards the Moon.

I was working for the GKN Research Centre, Wolverhampton at the time, but was seconded for a project at Shotton Brothers Ltd., a subsidiary of GKN, in Halesowen on the day of the launch. Some of us were able to listen to the Launch Control commentary live on portable radios – I don’t recall much work being done that afternoon!

The Lunar Lander, call sign “Eagle”, landed on Moon 20:17 UT on Sunday July 20 with about 25 seconds of descent-braking fuel left. They had expected about 90 seconds, but the terrain was much more inhospitable than had been anticipated and Neil Armstrong had to take over from the automatic systems, find a suitable spot, then bring the craft down manually.

The first words spoken from the surface of the Moon were not Armstrong’s “one small step for man” speech, but Buzz Aldrin’s technical announcement as he called out navigation data to Armstrong “Contact light! Okay, engine stop.” (It always sounds like “Contact lights” to me, but the official version is in the singular.)

It was a beautiful summer evening here on Earth – well, certainly in Kidderminster – and realising that Moon would set locally in a couple of hours time and that in less than 24 hours the astronauts would have left the Moon, I rushed into my garden to see the Moon, about 16° above the SW horizon, with the first two Moon-landing Earthmen on it! Nerd or what?

Some technical housekeeping was then required after which the flight plan called for a sleep period for the astronauts, but understandably they wanted to get on with the Moonwalk. Armstrong descended onto the Moon’s surface at 02:56 UT on Monday, 21st July, 1969. (It’s ironic that, because of world-wide civil time-zones, the Moonwalk occurred on 20th July in the USA whereas the officially recognised date the world over is 21st July!)

On the way down the ladder, Armstrong activated the black-and-white TV camera attached to the Lander, and although it was amazing to see live television from the surface of the Moon, the picture quality was disappointing. This was because NASA was using a slow-scan system which sent ten frames per second with a resolution of 320 lines and which was incompatible with public TV systems around the world. So they transmitted the image simply by viewing it with a conventional TV camera, this technically crude method causing significant loss in picture quality.

Armstrong then spoke his famous first words from the surface of the Moon: “That’s one small step for man, one giant leap for mankind”, and shortly afterwards, Aldrin joined Armstrong on the Moon’s surface.

Although ostensibly a photo of Buzz Aldrin, it also contains Neil Armstrong - reflected in Aldrin's visor!

They spent the remainder of the 2½ hour Moonwalk undertaking a variety of tasks: photographing the Lander so that NASA engineers would be able to see its condition; testing methods of moving around, including hopping; collecting over 20 kg (47 lbs) of Moon rock; and setting up lunar monitoring equipment, including a passive seismograph and a laser ranging reflector.

After less than 24 hours on the Moon’s surface, the Eagle took off again, rendezvousing with the Lunar orbiter, and making a thankfully uneventful return to the Earth. Apollo 11 had successfully met John F Kennedy’s belief that “ … this nation should commit itself to achieving the goal, before this decade is out, of landing a man on the Moon and returning him safely to the Earth … “ with just over 5 months to spare!

Despite all the technology that originated from the Apollo project (and, no, I don’t mean non-stick frying pans – how about the microprocessor that has had the most profound influence on the lives of all of us?) some people still ask what use it was. To quote a story told by the late American astronomer Carl Sagan in his book “Broca’s Brain”: “… British physicist Michael Faraday was visited by his monarch, Queen Victoria. Among Faraday's many celebrated discoveries … were more arcane findings in electricity and magnetism, then little more than laboratory curiosities. The Queen asked Faraday of what use such studies were, to which he is said to have replied, ‘Madam, of what use is a baby?’”

What the Moon looked like from the U.K. at the moment of touchdown of Apollo 11.

How many people remember looking at the Moon just after the touchdown of Apollo 11 at 20:17 UT (Universal Time – add one hour to convert to BST) in the evening of 20th July, 1969? Well, I do for a start – it was a beautiful clear sky here in Kidderminster.

Our diagram, above, shows precisely the phase of the Moon and the position of the terminator at that moment. The landing site, Tranquillity Base, lies close to the southern edge of the Sea of Tranquillity (“Mare Tranquillitatus”), one of the dark patches on the right-hand side of the picture.

The nearest named feature on the Moon’s surface to Tranquillity Base is (as far as I am aware) the tiny craterlet Moltke, shown as a red dot in the picture with the name in yellow script. The approximate position of Tranquillity Base is easy to find with a pair of binoculars or even the naked eye, but you won't be able to see Moltke – a powerful telescope is required to see this 4 mile diameter Lunar surface feature. And you certainly won’t be able to see the remnants of the Lunar Lander, which is only a few metres across; a telescope with an objective mirror about 100 metres diameter would be required for that. (One estimated cost of building such a telescope is greater than the cost of going to the Moon itself!)

What the Moon looked like from the U.K. at the same date and time in 2009.

So what did the Moon look like from this part of the U.K. at 20:17 UT on the evening of 20th July, 2009? Well, the Moon was only about 30 hours away from being a New Moon, so if you could have seen it at that time, it would have been only a tiny crescent sliver with Tranquillity Base in the dark, shadow area. But as it the Moon set at 19:27 UT - nearly an hour before the touchdown time of 20:17 UT - it wasn’t visible then in the U.K. at all! Sorry!

Martin Humphries.