Space Sunday: the last man on the Moon

Eugene Andrew "Gene" Cernan, Commander, Apollo 17, in the Taurus-Littrow valley, December 1972
Eugene Andrew “Gene” Cernan, Commander, Apollo 17, in the Taurus-Littrow valley, December 1972. Credit: Harrison Schmitt / NASA via Getty / AFP

Eugene Andrew “Gene” Cernan, Captain, United States Navy (retired) and former NASA astronaut, passed away on Monday, January 16th 2017 at the age of 82. The commander of Apollo 17, he was – and currently remains – the last man to walk on the surface of the Moon, in what was arguably the most significant of the Apollo lunar missions.

Born in Chicago, Illinois in March, 1934, he attended Purdue University, Indiana, where he gained a Bachelor of Science degree in Electrical Engineering in 1956. While at the university. he took a commission as an Ensign in the U.S. Naval Reserve Officers Training Corps. Following his graduation, he attended U.S. Naval Flight Training, qualifying as an attack pilot, and went on to log more than 4,000 flying hours in jet aircraft and completed over 200 aircraft carrier landings.

In 1963, Cernan completed his education under the auspices of the US Navy, obtaining a Master of Science degree in Aeronautical Engineering from the  U.S. Naval Postgraduate School. Later that same year, he was selected by NASA as a part of their third intake of Astronaut Candidates, and participated in both the Gemini and Apollo programmes.

His first flight into space, aboard Gemini 9A started with a tragedy. The original Gemini 9 flight had been scheduled for Elliot See and Charlie Bassett. However, when they were unfortunately killed when their NASA aircraft crashed at the end of February 1966, the mission was re-rostered as Gemini 9A, and Cernan and his flight partner, Thomas Stafford, were promoted from back-up to prime crew.

Gemini 9A was to prove a mission plagued with misfortune. The first attempt to launch the mission, in May 1966 had to be scrubbed when the uncrewed Agena Target Vehicle Gemini 9A would rendezvous and dock with once in orbit  was lost not long after launch. This required a delay while a second Agena was prepared for flight, being launched on June 1st, 1966. However, once in orbit, telemetry from the vehicle suggested a launch shroud had not been correctly jettisoned.

On approaching the Agena following their launch on June 3rd, Stafford and Cernan confirmed the sections of the shroud, although open, had failed to detach, leaving the vehicle looking – in Stafford’s words – “Like an angry alligator out here rotating around”. He and Cernan indicated they were willing to carefully approach the Agena and try to nudge the shroud elements clear of the docking adapter, but mission control nixed the idea, fearing the Gemini vehicle might be damaged in the process. Instead, the crew rehearsed docking runs with the target vehicle and tested rendezvous abort procedures.

The "angry alligator" of the Agena target vehicle with launch shroud elements still attached, as seen from Gemini 9A on June 3rd, 1996. The nose of the Gemini vehicle can be seen at the top of the image, and the craft were some 20.3 metres (66ft) apart
The “angry alligator” of the Agena target vehicle with launch shroud elements still attached, as seen from Gemini 9A on June 3rd, 1996. The nose of the Gemini vehicle can be seen at the top of the image, and the craft were some 20.3 metres (66ft) apart. Credit: NASA

On the third day of the flight, Cernan became the third man (and America’s second) to walk in space. However, this part of the mission also proved troublesome. The Gemini spacesuits were not water-cooled, and had to be “inflated” prior to egressing the vehicle. Cernan found the latter made the suit almost completely inflexible and a serious impediment to his movement. This meant he had to exert himself a lot more, and because the suit had no proper cooling, he face the genuine risk of suffering heat prostration.

Nor was this all; the build-up of heat meant his helmet faceplate fogged to the point where he could barely see, and there were serious concerns about him getting back into the Gemini. His EVA was  curtailed without all goals being met, and after 128 minutes in space, Cernan eventually made it back inside the spacecraft. As a result of this experience, the Apollo spacesuits were redesigned to incorporate an undergarment using a water circulation system to cool the wearer – and approach still used in modern space suits.

Cernan next flew in space in May 1969 as part of the final Apollo dress-rehearsal mission for an actual landing on the Moon. Apollo 10, which saw Cernan and Stafford again fly together, and joined by John Young, became the second crewed mission to orbit the Moon (the first being Apollo 8, in December 1968), and the fourth crewed flight of Apollo overall. The focus of the mission was for Stafford and Cernan to pilot the Lunar Module to just 15.6 km (8.4 mi) above the lunar surface, gathering critical data which would allow the powered descent systems aboard future Lunar Modules to be correctly calibrated for their missions.

Gene Cernan in 1969, ahead of the Apollo 10 flight during a NASA press conference. A Snoopy toy sits next to him, indicative of the Apollo 10 lunar module call sign
Gene Cernan in 1969, ahead of the Apollo 10 flight during a NASA press conference. A Snoopy toy sits next to him, indicative of the Apollo 10 Lunar Module’s call sign. The Command Module was called Charlie Brown. Credit: NASA

In most respects, the Apollo 10 Lunar Module was fully capable of flying a mission to the surface of the Moon – it just lacked sufficient propellent in its ascent engine fuel tanks to make a successful flight back to rendezvous with the Command Module.  This later prompted Cernan to joke, “A lot of people thought about the kind of people we were: ‘Don’t give those guys an opportunity to land, ’cause they might!’ So the ascent module, the part we lifted off the lunar surface with, was short-fuelled. The fuel tanks weren’t full. So had we literally tried to land on the Moon, we couldn’t have gotten off.”

Apollo 10 reached lunar orbit on May 21st, 1969, three days after launch, and remained there for a further three days, completing the Lunar Module tests in the process, before returning to Earth. It was a mission which set both records and firsts. It was the first (and only) Apollo Saturn V mission to launch from Pad 39B at Kennedy Space Centre; it was the first (of only two, the other being Apollo 11) Apollo missions to comprise veterans of previous missions into space.

As a result of the Moon’s elliptical orbit placing it close to apogee (the point farthest from the Earth), the mission also meant the Apollo 10 crew became the humans who have had the greatest distance between themselves and their families. At one point the distance between the Apollo 10 spacecraft, passing around the Moon’s far side, and Houston, Texas, where the crew’s families lived, was 408,950 km (254,115 mi). Because of that extra distance between the Moon and Earth, Apollo 10 had to burn its Service Module engine for longer than other Apollo missions, meaning that on May 26th, 1969, a few hours ahead of splashdown it officially set the record for the highest speed attained by any crewed vehicle thus far flown: 39,897 km/h (11.08 km/s or 24,791 mph).

The Apollo 10 Command Module, Charlie Brown, is now on display at the Science Museum, London. Credit: The Science Museum
The Apollo 10 Command Module, Charlie Brown, is now on display at the Science Museum, London. Credit: The Science Museum

Cernan’s next opportunity to fly in space could have been as the Lunar Module pilot for Apollo 16 in 1972. However, despite the fact that Apollo 18 and Apollo 19 had been cancelled by President Richard Nixon in 1971 (Apollo 20 having been cancelled in 1970 so the Saturn V could be used for the Skylab project) and there was a risk that Apollo 17 might still be cancelled, he opted to hold out for the Commander’s position on that mission.

While the mission wasn’t cancelled, NASA opted – against Cernan’s initial wishes – to remove Lunar Module pilot Joe Engle from the mission and replace him with geologist Harrison Schmitt – the only professional geologist to so far fly to the Moon. Schmitt had been scheduled to fly with Apollo 18, and his appointment to the Apollo 17 mission was seen as calming upset within the science community that no scientist astronaut would fly to the Moon after astrophysicist Curt Michel resigned from the Astronaut Corps.

The Apollo 17 crew: seated in the lunar rover replica is Gene Cernan, with Harrison Schmitt to the left behind him, and Ronald Evans to the right
The Apollo 17 crew, 1972: seated in the lunar rover replica is Gene Cernan, with Harrison Schmitt to the left behind him, and Ronald Evans to the right, and the Saturn V launch vehicle on the pad behind them. Credit: NASA

Apollo 17 lifted-off at 00:33 EST (05:33 UTC) on December 7th 1972, marking it as the only night-time launch of a Saturn V. Around 500,000 were present at Kennedy Space Centre to witness the launch, and the rocket’s ascent through the night sky was seen 800 km (500 mi) away. Three hours after arriving in orbit, final checks complete, the motors on the rocket’s third stage were fired, and Apollo 17 headed for the Moon.

Given this was the last of the Apollo lunar missions, considerable thought had been given to the landing site, with numerous options – including one on the lunar far side – being considered. In the end, the Taurus-Littrow valley was selected as a landing site, as it presented options for a wide range of lunar geology, including access to old highland material and much younger volcanic material.

The Lunar Module, call sign Challenger, touched-down in  Taurus-Littrow at  14:54:57 EST (19:54:57 UTC) on December 11th, 1972. The first EVA commenced four hours later, Cernan and Schmitt having spent the intervening time reconfiguring the LM’s interior for surface operations. For the first EVA, they spent most of their time setting up science experiments and deploying equipment such as their lunar rover – which Cernan accidentally damaged very slightly. Duct tape allowed for temporary repairs sufficient to allow the pair to use the vehicle on excursions away from the lander.

In all, Cernan and Schmitt performed three EVAs, each lasting over seven hours, with the 2nd and 3rd including extensive drives in their lunar rover. They collected over 100 kg (221 lb) of rock samples, discovered some unusual orange-coloured regolith, and visited numerous locations of scientific interest.

Cernan (l) and Schmitt aboard the Apollo 17 Lunar module. Credit: NASA
Cernan (l) and Schmitt aboard the Apollo 17 Lunar module. Credit: NASA

As a part of the final EVA, Schmitt and Cernan unveiled a plaque mounted on the side of the Lunar Module’s descent stage, commemorating both their own time on the Moon and the Apollo mission as a whole, with Cernan expressing some of his thoughts thus:

I’m on the surface; and, as I take man’s last step from the surface, back home for some time to come – but we believe not too long into the future … And, 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.

At the end of the EVA, Schmitt boarded the Lunar Module first, leaving Cernan as the last man on the Moon, before he also climbed back into their vehicle. 24 hours after starting out on that last EVA, the two men successfully used the ascent stage of their LM to return to lunar orbit and a rendezvous with Ronald Evans aboard the Command and Service Module.  Challenger’s ascent stage was jettisoned, and the Service Module’s motor fired to bring them back to Earth. The Command Module, call sign America, splashed down in the Pacific Ocean at 19:24 UTC on December 19th, 1972, bringing the Apollo lunar era to a close.

Gene Cernan never flew in space again. He retired from the US Navy and NASA in 1976, entering the private sector, where he would establish his own company. He later became a regular on ABC television, presenting a programme on health, science, and medicine. He appeared in several documentaries on the Apollo era and US space exploration, and in 2010, testified alongside Neil Armstrong in opposition to the cancellation of the Constellation programme, and he remained critical of NASA’s leadership through 2010-2012.

His memoir, Last Man on the Moon, was published in 1999. In 2016, and after a 9-year development cycle, a documentary of the same name and based on the book was released by British film-maker Mark Craig. You can see an interview with Cernan and Craig on YouTube, and the trailer is embedded below.

Also in 2016, and on top of numerous awards and citations presented to him throughout his life, Cernan received the Neil Armstrong Outstanding Achievement Award from the US National Aviation Hall of Fame. It was given in part to honour his advocacy for “personal empowerment and development, especially among youth”, and in part in recognition of his contribution to human space flight, and his support for the revival of America’s human exploration of space.

Details on the cause of his death have not been made available; however, Cernan will be interred in a private service at Texas State Cemetery with full military honours on January 25th, 2017.  He is survived by his wife, Jan Nanna Cernan, by whom his has two daughters, Kelly and Danielle, and his ex-wife, Barbara Jean Atchley, by whom he has one daughter, Tracy, and with whom he remained friends after their divorce.

And in Brief

NASA To Determine Juno Burn in February

NASA’s Juno pace vehicle will make its next close flyby of Jupiter on February 2nd, 2017. However, the flyby will not include a burn of the vehicle’s main engine in order to reduce its current 53.5 day orbit around the planet to just 14 days. This means that all of the science experiments and systems should be running aboard the vehicle as it passes over Jupiter’s cloud tops.

Juno had been expected to make an orbit-reducing engine burn during its October 2016 close pass around Jupiter. However, telemetry indicated a potential issue with a set of valves in the motor system. Since then, investigations have been ongoing into the possible cause of the problem and to determine if it might be rectified, and / or whether and engine burn can take place. The decision on this is now expected later in February, meaning the first opportunity to carry out the manoeuvre will be towards the end of March, when Juno makes its next close pass over Jupiter.

Landing On Pluto

A landing on Pluto, either by a crew or – more likely – a robot vehicle, is not going to be something which will occur any time in the next two or three decades. However, using more than 100 images gathered by the New Horizons spacecraft during a 6-week period in June / July 2015 as the vehicle made its historic high-speed flyby of the Pluto system, NASA has produced a movie of what such an event might be like.

Starting from a distant view of the planet, the film show Pluto and its largest moon, Charon spinning around one another as the vehicle approaches, and culminates in a “landing” on the shoreline of Pluto’s informally named Sputnik Planum. It has been made by interpolating black-and-white frames based on what scientist know Pluto looks like between the actual images in order to give a sense of the a smooth ride down to the surface. Low-resolution colour from the Ralph system on New Horizons was then added to give the best available colour simulation of what it would look like to descend from high altitude to Pluto’s surface.

One thought on “Space Sunday: the last man on the Moon

  1. I was lucky and saw the launch of Apollo 17 in person but also young enough to not realize it was the last mission to the Moon for such a log time. 😦


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