Apollo 12 to the end and beyond
Tuesday 16th March, 2021
Our speaker (on Zoom) was Pete Williamson who talked to us about "Apollo 12 to the End and Beyond". He is very active in astronomy outreach and gives talks to numerous organisations including schools, colleges, societies, and the general public. He is also a consultant and imager for many educational remote-access telescopes across the globe such as Slooh and the Faulkes Telescopes, also offering workshops on how to use them. He has his own radio station named "Astro Radio Earth" which is volunteer-run and features both astronomy and a wide range of music. He had visited us previously to talk about the earlier Apollo program in July 2019 with his presentation entitled - "The Moon: from Myth to Landings and Beyond" and so this talk covered the rest of the Apollo spaceflights.
He began by saying that the astronaut crew of Apollo 12, Pete Conrad, Alan Bean and Richard Gordon, were good friends unlike some of the other Apollo crews. They launched on 14th November 1969 and their Saturn V rocket had the misfortune to be struck twice by lighting as it lifted off from its launch pad. This surge of electricity knocked out the rocket's computers and Pete Conrad had to reboot them in order to reach orbit.
Five days later Conrad and Bean landed on the lunar surface in Oceanus Procellarum (Ocean of Storms), only 73 metres from their target spot. They spent roughly a day on the surface and struggled somewhat in setting up the Apollo Lunar Surface Experiments Package but did manage to gather various bits of the Surveyor 3 probe to return to Earth for examination. They were planning to send live colour television pictures back to Earth but, sadly, Bean accidentally pointed the camera at the Sun, destroying the camera's sensor. All three made it safely back to Earth, with their capsule splashing down in the Pacific Ocean on November 24th.
Apollo 13 is the mission where the crew actually made it around the Moon but did not land. Their Saturn V rocket launched on April 11th, 1970 but it was not a smooth launch as the second-stage engine shut down roughly two minutes early. Fortunately, the four outboard engines and third stage were able to burn longer to compensate.
Then, later on their way to the Moon astronauts Jim Lovell, Jack Swigert and Fred Haise had to resort to extreme measures to stay alive after an oxygen tank exploded in the Service Module. They were too far from Earth to just turn round and come back so it was decided that they should loop around the Moon using the Lunar Module as a lifeboat. The only problem with this was that it was only designed for two people for 45 hours whilst they were on the lunar surface, and although they had lost oxygen in the explosion it was the build up of carbon dioxide, little power to keep them warm, and lack of water that were the main problems.
NASA engineers solved the carbon dioxide problem by getting the astronauts to construct makeshift connectors that would use command module to scrub the air in the lunar module that was their lifeboat. However, the astronauts would still have to put up with low temperatures and rationing the water. Despite the hardship, the astronauts survived, and their capsule was recovered from the South Pacific on April 17th to the relief of a worldwide audience who were following this sudden turn of events.
The following mission, Apollo 14 launched on January 31st, 1971 carrying the astronauts Alan Shepard, Edgar Mitchell and Stuart Roosa smoothly to the Moon but there were other problems. Before they left Earth orbit they had to retrieve the lunar module out from is launch storage position inside the Saturn V rocket using the command module. For some reason the docking mechanism was not working and after five attempts to dock they tried a somewhat unorthodox technique which finally worked. Shepard and Mitchell also had problems with the lunar module's descent to the lunar surface when firstly its computer suffered a glitch that was hastily fixed by uploading new software and then the radar failed to locate the surface. Fortunately, rebooting the computer fixed the problem and they landed safely. Later, engineers found out that it was the software patch that had actually caused the problem with the radar.
The astronauts placed a US and United Nations flag near their landing site in Frau Mauro, which would have been the landing site of the Apollo 13 mission. They had the use of a wheeled trolley to carry their experiments to various locations and, in a lighter moment, during their busy time on the surface Shepard used the handle of their sample device together with the head of a six-iron golf club to hit six golf balls. Although he says that the balls went "miles, and miles, and miles" he was more than likely exaggerating as four of the six golf balls were brought back to Earth on February 9th.
Apollo 15 set off on July 26th, 1971 for a landing near Hadley Rille and this mission marked the first use of the lunar rover. Onboard were astronauts David Scott, Alfred Warden and James Irwin. They managed to cover just under 30 km using the lunar rover, but it kicked up moon dust that ended up on the batteries that powered it and they overheated, so they ended up having to cover them. This mission also included an EVA (extravehicular activity) i.e. a spacewalk lasting 40 minutes on their way back to Earth, to recover a camera on the outside of the command module. Their capsule splashed down in the Pacific Ocean on August 7th.
The penultimate mission, Apollo 16, launched on April 16th, 1972 carried astronauts John Young, Charles Duke and Ken Mattingly. They did have problems both on their way to the Moon and in lunar orbit that delayed their landing and cut short the mission by a day. On the way there, the astronauts had to make changes to the computer in the Command and Service Module (CSM) to correct its trajectory and the landing was delayed due to problems with a system connected to the CSM's main rocket engine. On the lunar surface, in the Descartes highland region, Young and Duke collected "Big Muley", which was the largest rock sample of the Apollo missions. They were also able to use a special telescope to look at distant objects in ultraviolet light as there was no atmosphere to block these wavelengths of light. They returned to Earth eleven days later.
The final mission, Apollo 17, consisted of astronauts Eugene Cernan, Ronald Evans, and Harrison Schmitt, who launched at night on December 7th, 1972. This was the first mission to have no one on board that had been a test pilot and it also broke a number of the Apollo spaceflight records — longest Moon landing, longest total lunar excursions, largest weight of lunar samples, longest time in lunar orbit and most lunar orbits. This mission was also unusual as Schmitt was a primarily a scientist — a professional geologist who led the search for rock samples in the Taurus-Littrow valley. The Apollo programme drew to a close when they all returned safely (with five mice that were part of an onboard biological experiment) on December 19th, 1972 when their capsule splashed down into the South Pacific Ocean.