Just before 6pm on a December evening 50 years ago, an American astronaut wrote his daughter’s initials in the lunar dust and prepared to clamber back into his vehicle to lift off from the Taurus-Littrow valley.
Before doing so he delivered a stirring, short prepared speech, bringing to an end an extraordinary decade in space exploration, which had culminated in the dramatic first landing by human beings on the moon three years before.
Gene Cernan, the commander of the Apollo 17 mission, concluded by saying: “As we leave the moon at Taurus-Littrow, we leave as we came and, God willing, as we shall return: with peace and hope for all mankind.”
Rumour has it that these were not the actual last words spoken on the lunar surface. Reportedly, as he pressed the buttons to blast off from the moon, Cernan’s final comments were more prosaic and earthy, centring on some variation of the words “let’s get this mother out of here”.
Cernan’s prepared speech aimed to provide hope for an American manned space programme that had beaten the Soviet Union and met the challenge set by John F Kennedy to send a man safely to the moon before the end of the 1960s and return him safely to Earth.
But by 1972 the public euphoria of the first moon landing was over. The future was uncertain.
As Apollo 17 made its way home, the then president Richard Nixon forecast, correctly, that men might have walked on the moon for the final time in the 20th century.
The United States was on the verge of losing the war in Vietnam and there were very real, down-to-earth crises of poverty, violence and inequality in American cities. The large cost of the space programme was coming under fire. Budget cuts had already led to the cancellation of further moon missions.
Earlier ambitions of follow-up explorations of Mars had been shelved and the planned new US space initiatives — the early orbital laboratory Skylab and the space shuttle — were based around ventures to relatively low Earth orbit. The exploration by humans of the other planets would be achieved vicariously through machines.
Cernan’s lofty hopes of going back to the moon remained unfulfilled for five decades.
In the early afternoon Irish time on Saturday, at a site close to the Atlantic Ocean in Florida about an hour east of Orlando, the official clock started ticking down towards the launch of arguably the most important space initiative in years.
The United States is finally preparing to return human beings to the moon and potentially onward to Mars.
Bill Nelson, administrator of the US space agency Nasa, said this weekend that, unlike in the 1960s, on this occasion astronauts would not just be on the lunar surface for a few hours or a couple of days at most. Nasa wants to build a base there and for humans to stay on a longer-term basis and to learn and develop technologies to allow for a human mission to Mars by the late 2030s.
This weekend, attached to a launch tower about three miles from the mission control building at the Kennedy Space Center, a large 300ft orange-coloured rocket with a white nose cone and two white boosters stands ready.
It is scheduled to blast into space at 8.33am local time on Monday morning, about 1.30pm in Ireland, launching the era of the Artemis programme.
In Greek mythology Artemis was the twin sister of the god Apollo. Apollo, of course, was the name given to the famous US manned space programme of the 1960s.
The Artemis 1 mission is effectively a test flight and will not have people on board, only mannequins covered in sensors.
It will seek to assess newly developed equipment, technology and systems which, if successful, will facilitate a human mission to lunar orbit in 2024 and the landing of astronauts on the moon’s south pole in 2025.
All of Nasa’s original 12 astronauts who walked on the moon were white men. The space agency plans the crew who follow them in the future will include the first woman and person of colour.
Mike Sarafin, the mission manager for Artemis I, told a press conference in Florida on Saturday that the mission next week was essentially a purposeful stress test of the rocket and the space craft.
“We will learn a great deal from the Artemis I test flight. And through this experience, we will change and modify anything necessary to prepare ourselves for a crewed flight on the very next mission.”
The two key pieces of technology and equipment to be put through their paces are the rather inelegantly named space launch system (SLS) rocket and the Orion space craft.
The rocket will propel Orion out of Earth’s atmosphere and then on to the moon, while the space craft itself will in future carry the astronauts to lunar orbit and then safely home.
The SLS is the most powerful rocket ever built, but it is years behind schedule and the flight next week will be its first real test as a heavy lift vehicle.
Separately, Nasa scientists will carefully monitor the heat shield on Orion which will be crucial if astronauts are to be brought safely back to Earth.
Nelson said the shield will have to withstand heat of up to 5,000 degrees Fahrenheit as it hits Earth’s atmosphere at Mach 32 on the way back from the moon.
Not only is the planned mission profile of Artemis different from that of Apollo in the 1960s, the whole space programme has changed vastly. It is no longer confined to governments and nation states. The private sector will play a key role. The Nasa astronauts who will walk on the moon in 2025 or so will have to rendezvous with a separate lunar lander which is being developed by Elon Musk’s Space X company.
In the longer term, Nasa plans to establish a mini space station in orbit around the moon — to be known as gateway — where space craft from Earth would dock and from which astronauts could be ferried to and from the surface.
Musk’s company, separately, is also developing its own heavy lift rocket designed to carry people to the moon and Mars.
The new Artemis programme is also not exclusively American. The European Space Agency ESA is overseeing the development of the European service module that provides air, electricity and propulsion which will power the Orion craft to its destination and back to Earth.
The Artemis project will certainly also not be cheap to implement.
In a report earlier this year Nasa auditors reported that each of the first four Artemis missions would likely cost about $4.1 billion — eight times the original estimate in 2012.
The auditor maintained this estimate only covered production costs and ground operations, “and does not include development costs required to get the Artemis program to this point in time.”
Overall, Artemis 1 is set to be a 42-day mission.
Orion, after it separates from the SLS rocket, will take about 10 days to reach the moon, where it will enter into a sweeping orbit which will see it at times as close as 60 miles from the surface to nearly 40,000 miles away.
All going well, the Orion craft will splash down into the Pacific Ocean off the coast of California on October 10th.
But the mission is not just about going to lunar orbit. Along the way it will deploy 10 miniature satellites known as cubesats which will have a number of tasks including looking for water on the moon and studying deep-space radiation.
As Monday approaches, Nasa will be closely watching the weather. The last few days in the area have seen temperatures in the 90s but with heavy rain and thunderstorms that made it virtually impossible on occasions to see cars driving ahead.
Weather experts locally have predicted a 70 per cent chance of favourable conditions for the Artemis 1 launch.
Fifty years ago, one of the reasons given for the cancellation of the Apollo programme was dwindling public interest.
As the United States prepares to return to the moon, hotels close to the Kennedy Space Center are full up. Contractors involved in the programme have booked hotels in Orlando as rewards for key personnel. About 700 local and international media have been given accreditation by Nasa. Overall, local authorities in the area are estimating that between 100,000 and 200,000 people could turn up in the vicinity of the Kennedy Space Center to see the launch on Monday, which is also expected to be witnessed by US vice-president Kamala Harris.