It was four decades and a week ago that three orange parachutes opened and a small, heavily burnt cone descended gently into the Pacific Ocean. The date was April 17, 1970, the mission was Apollo 13, the spacecraft was Odyssey and its inhabitants were Lovell, Swigert and Haise.
The rescue of the three astronauts was an immense effort of blood, sweat and tears across the United States and abroad. All over the world, there was only one thing on the news, one thing to talk about. The intense willpower to return the men was eventually successful.
The overriding feeling back on Earth was that man had won its first great battle with space, almost as if an alien invasion had been fended off. To some, it was a far greater achievement than any of the moon landings. Those had been, like the recent election debates, out of the simulator.
To others, it was the moment that the human race became a spacefaring people. There are many alternatives to this: the first satellite, the first astronaut, the first spacewalk, even the first disaster. Bill Anders' striking, electrifying earthrise picture provides compelling evidence that Apollo 8 was the breakthrough.
By now, you are probably assuming that the title of this article is a typo, and even if I can type, what did Apollo 16 do anyway? Well, the answer is, as you probably thought, nothing particularly momentous to the non-geologist.
On April 16, 1972, John Young, Charlie Duke and Ken Mattingly took off for the moon. Young was already thought of as something of a grizzled geriatric then, on his fourth spaceflight, long before he commanded the first Space Shuttle flight and went on like Methuselah. Mattingly, meanwhile, had famously had to pull out of Apollo 13 just days before launch.
Command module Casper reached the moon without a hitch, but once it entered lunar orbit, it seemed that Mattingly's misfortune would rear its ugly head again. The engine of his command module appeared to fail after Young and Duke had departed for the lunar surface in Orion.
Mattingly was certain the landing was off, and he thought back to an encounter with a technician in the Saturn V rocked days before launch. "It won't fail because of me", the man told the astronaut. This, said Mattingly, was the spirit and the work ethic of Apollo in a nutshell. And he thought he had broken the chain.
Eventually, though, it was decided that the problem - which made Young and Duke orbit the moon for around six hours - was a storm in a teacup. Invariably, the three people least concerned about the risks involved with the mission were the three men in space. Come on, they would say, let's not die wondering.
Apollo 16 was part two of three in the 'geology missions', or J-missions, in the Apollo programme. The first few lunar landings were simply symbolic, and NASA struggled even to pretend they had any scientific benefit, other than procuring fairly reliable evidence that the moon is not made of cheese.
The mission was to the Descartes highlands, and followed up Apollo 15's visit to the foot of Mons Hadley, where the Lunar Rover had first been used. The geology team, headed by Bill Muelburgher, had examined every rock brought back from previous missions and had created a convincing hypothesis that the Descartes region had once been volcanic.
Over three moonwalks, this theory was systematically dismantled by the discovery of countless breccias (impact-formed rock) around Descartes. All the astronauts on the J-missions spent almost as long practising geology, under the tuition of Lee Silver and Farouk El-Baz, as they did in the simulator.
Neither the moonwalkers nor anybody else put a great deal of thought to the lack of volcanic rocks at Descartes; Young caused more concern by breaking a heat flow experiment, much to the dismay of its supervisor, Mark Langseth. Meanwhile, the lunar rover travelled at around 11 mph, still a lunar record.
The lunar rocks were returned to Earth, as were Young, Duke and Mattingly in perfect health, and the observations of the moonwalkers were quite correct. The geologists would have to reformulate their hypotheses quite considerably after the findings of Apollo 16.
But this was the beauty of the mission. Man had travelled to the stars to see its knowledge proved, but it had instead been convincingly broken down. The human race remained complete ignoramuses about the vast expanses of space, or at least lunar rock formations. But Apollo was the first step towards turning this round.
Leading space writer Andrew Chaikin1 notes that Apollo was the "last great act [the United States] has undertaken out of a sense of optimism". Other missions are rightly more memorable and awe-inspiring, but the simple human incorrectness of Apollo 16 - even on an insignificant issue - made it great too.
And in an optimistic age, it was taken as a mistake to learn from and a means for progress, not a humiliating splashdown.