Try Again Apollo

With Apollo 13, NASA had dodged a bullet. The flight had very nearly killed its crew and, as always happens when it is hit by traumatic events, NASA needed a hiatus to investigate and understand what had disrupted Odyssey's service module. Although there were calls both from inside and outside the administration to end Apollo before someone got killed, its managers kept faith with it. The programme of exploration they instituted, now almost forgotten, visited immensely beautiful regions with spectacular vistas. Enhanced equipment allowed crews to explore further from the LM, and although the results from these missions had little political impact, their prodigious scientific output now underpins our understanding of the Solar System.

Apollo 14 returned the programme to the Moon to achieve what its predecessor had set out to do; visit the Fra Mauro area to gain insight into the formation of the Imbrium Basin. The precise target for the lunar module Antares was near an impact feature dubbed Cone Crater. Its attraction came from a useful property of crater formation whereby, when an impactor hits the ground, it removes the target rock such that the most deeply excavated material ends up at the crater's rim with successively shallower material deposited at increasing distances in the form of an ejecta blanket. Therefore, by having the surface crew of Alan Shepard and Edgar Mitchell radially sample this blanket as they walked towards its rim, geologists hoped to use Cone Crater as a convenient 25-million-year-old 'drill hole' to sample down through the great ejecta blanket of the Imbrium Basin impact itself, now thought to have occurred 3.91 billion years ago.

The launch from Earth on 31 January 1971 was successful. After checking the spacecraft out in Earth orbit and heading for the Moon, Stu Roosa separated the CSM Kitty Hawk, turned around and attempted to dock with the LM Antares. The docking was unsuccessful and five further attempts were required to capture the lander. At the Moon, just before Antares was due to begin its final descent to the

Apollo 14's LM Antares and the landing site at Fra Mauro.

surface, an intermittent short circuit threatened to abort the mission as soon as its engine ignited. It required a virtuoso engineering effort between mission control and the crew to deftly reprogramme the computer byte by byte to work around the problem.

Being the last of the H-missions, the surface crew had two excursions outside. On their first day, Shepard and Mitchell set up a second ALSEP science station and explored their locale. The second day was set aside for a trek of over a kilometre across the hummocky plain and up a ridge to approach the rim of the 370-metre Cone Crater. The climb proved to be tiring and, on nearing the summit, they had difficulty locating the crater within the monotonously undulating terrain. They had come 400,000 kilometres to get to this rim and they were reaching the limits of their oxygen supply. With time running out, they collected a clutch of samples and turned back. Analysis later showed that they had been within 30 metres of Cone's rim, near enough to gather material from deep within the Imbrium ejecta.

Back at the LM, Shepard pulled off a famous stunt by attaching a genuine golf club head to the shaft of one of his tools and hitting a golf ball he had smuggled to the Moon. Meanwhile, in lunar orbit, Roosa had planned an aggressive campaign of orbital photography with a high-resolution mapping camera attached to the hatch window. This was cut short when the instrument failed, and he had to improvise by carrying out some of the mission's photographic goals using handheld cameras and clever flying.

Apollo 14 was a highly successful mission that restored NASA's confidence and prepared it for the triumphs of exploration and science to come. It was also the last time lunar explorers were required to undergo a period of biological isolation after landing on Earth. The rocks they returned allowed scientists to probe the nature of the ejecta blanket from the Imbrium formation event. By seeing how other lunar features sat with respect to this event, geologists could now distinguish between pre-Imbrium and post-Imbrium.

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