Apollo 15

26 July – 08 August 1971

by Hamish Lindsay

Originally planned as the last of the simpler “H” missions, with only two excursions and no vehicular Rover, the cancellation of the last three Apollo lunar landings made NASA anxious to make the most of the remaining missions, so the more comprehensive scientific “J” missions were brought forward to Apollo 15.

The Apollo 13 mishap introduced a convenient delay in the program to help incorporate the hardware changes, as the “J” missions were designed to use the Apollo system capabilities to the limit, and to change the role of the astronauts from test pilots to explorers, preferably scientific explorers.

The Saturn V engines had been dramatically improved, allowing an additional payload of 3,175 kilograms. This was needed for the longer stays on the lunar surface; extra fuel for both the CSM and LM, more battery capacity for the LM, and the 209 kilogram weight of the Rover. In addition there was the Particle and Fields Satellite (P&FS), and a heavy SIM (Scientific Instrumentation Module) package built into the Service Module for detailed scientific observations of the Moon from lunar orbit.

Thought had been given to including a remote control for the Rover so that after the astronauts had left the Moon Houston could have driven the vehicle around and used the TV to explore the area. For instance, it could have driven to the bottom of the Rille, but budget limitations meant it was never funded.

The Apollo 15 crew with the Lunar Rover before their departure for the Moon. From left: James Irwin, LM Pilot, David Scott, Commander and Alfred Worden, Command Module Pilot. The adjustable high-gain dish antenna, gold-foiled TV camera and Lunar Communications Relay Unit (LCRU) under are clearly visible on the left. Worden’s left hand is on the Particle and Fields Subsatellite.

Apollo Television comes of age with Apollo 15

Apollo television began as an after-thought, in the beginning some even did not want it at all. The Apollo communications system had been designed to handle only low-resolution, slow-scan TV fit to into a 500 kHz bandwidth. In those days it was still black and white commercial television for the public, and Apollo 11’s first step onto the moon reflected the limitations of the time, the public glued to the fuzzy monochrome images, trying to figure out what they were really seeing.

Apollo 12’s television never got off the ground – in the first EVA the TV camera was inadvertently aimed at the sun and the camera’s SEC sensor was destroyed. Apollo 13 never reached the Moon’s surface, and Apollo 14’s television was limited to the landing site and had technical problems too, with bloomy images of astronauts looking like Casper the Ghost. Except for Apollo 13, after Apollo 11 the commercial television networks coverage to the public was apathetic, though the world did get to see Al Shepard’s golf swing at Frau Mauro.

Now Apollo 15 could show what television could really do. It was the first of what NASA called the technically advanced ‘J’ missions where the astronauts could range far from the LM on an electrically driven Rover vehicle, with EVA time doubled to nearly 19 hours. This time there was a newly designed, remotely controlled television camera for the Rover that promised clear pictures of the exploration at each stop. Hooked into the camera was a new unit called the Ground Commanded Television Assembly (GCTA), nicknamed ‘Gotcha’, allowing an operator seated at a console in Houston to control the Rover’s camera on the Moon.

A special package was mounted on the front of the Rover to communicate directly with the Earth tracking stations wherever the Rover was parked. Called the Lunar Communications Relay Unit (LCRU), it was a suitcase-sized box with an umbrella-like antenna, making the Rover a completely independent mobile TV studio. Though the astronauts could not use the dish antenna while driving, they could still talk to Earth through the LCRU using a low-gain unidirectional antenna. However there were times when television pictures were inadvertently transmitted to Earth through the omni antennas while the Rover was bouncing along the lunar surface.

Early on in the development program it was conceded that, even if the camera put out a good quality picture, there was no assurance that the video would retain that quality by the time it reached Houston. NASA and RCA mounted major efforts, quite apart from the camera and communications unit development, to discover elements that might degrade the video along the earth-based links and fix them. It was discovered, for example, that a receiver at one station could cause picture tearing. A particular model of processing amplifier could convert a slightly noisy received signal into very objectionable streaky noise. Certain filter types could cause ringing or ghosting. All of these potential glitches along the communications links were methodically fixed before the mission. Another example of the thoroughness of the Apollo team.

The crew

Deke Slayton picked a crew of aviators for the first scientific mission to the Moon – David Scott, 39, as Commander, Alfred Worden, 39, as Command Module Pilot and Jim Irwin, 41, as Lunar Module Pilot, with backups Richard Gordon, Vance Brand and Harrison Schmitt. The Air Force is in Dave Scott’s blood, his father a retired USAF General, and his wife, Ann Lurton, daughter of a retired USAF Brigadier-General. He had been out to the Carnarvon Tracking Station in June 1965 for Gemini 4 and while he was there went on a geological expedition to the Kennedy Ranges some 320 kilometres inland from Carnarvon. These Ranges are noted for their fossils, gemstones, and petrified wood. With Honeysuckle Creek appointed the Prime Station for the mission there were a lot of connections between Apollo 15 and Australia, especially when Apollo 15 sprang a leak during the mission like Cook’s Endeavour did on the Great Barrier Reef.

David Scott	Jim Irwin

Colonel David R. Scott, born on Randolph Air Force base in San Antonio, Texas, began studying at the University of Michigan before joining West Point where he graduated in 1954. Later he took a master’s degree in aeronautics and astronautics at MIT. He had already proved his cool in a life-threatening crisis in Gemini VIII with Neil Armstrong when a thruster locked open and sent them spinning out of control and the mission had to be aborted over China. Next he was Command Module Pilot under James McDivitt in Apollo 9.

Irwin and Worden were both rookies.

Lieutenant-Colonel James B. Irwin, born in Pittsburgh, married Mary Ellen, a former photographer’s model. He graduated from the US Naval Academy with a Bachelor of Science degree in Naval Science in 1951and went straight to a commission in the Air Force. In 1957 he completed a Master’s degree in Aeronautical Engineering and Instrumentation from the University of Michigan. In 1961 he wasn’t supposed to walk again after a horrendous plane crash when he suffered two smashed legs, a fractured jaw, and concussion that temporarily wiped out part of his memory. By sheer determination he fought to get his mobility back, to be twice rejected by NASA before finally being accepted as an astronaut in 1966.

Al Worden

Major Alfred M. Worden, born in Jackson, Michigan, graduated from West Point Military Academy with a military science degree in 1955, before he collected a master of science degree in astronautical and aeronautical engineering from the University of Michigan in 1963. He attended Randolph Air Force Base Instrument Pilots Instructor School in 1963 and served as a pilot and armament officer from March 1957 to May 1961 with the 95th Fighter Interceptor Squadron at Andrews Air Force Base, Maryland. He was a happy-go-lucky divorcee who played his baby grand piano for friends, and slept in a bed with a canopy of aluminium reflectors to help get him up in the morning.

With an all Air Force crew it was easy to pick their mascot Falcon as a name for the LM, but it wasn’t until they were working with a geologist that Scott happened to pick up a children’s book on explorers that he came across Captain Cook and his exploits in the Endeavour. He thought, “Cook made the first purely scientific expedition in history, and ours was the first extensive scientific expedition to go to the moon,” so the Apollo 15 Command Module has gone down in history as the Endeavour.

Scientist/Apollo 17 Astronaut Jack Schmitt had enjoyed a long association with his Professor of Geology and Geochemistry, Leon (Lee) Silver, and when Schmitt and Scott met it did not take much persuasion to pull Scott and Irwin into the geology training. Silver became Scott’s mentor, organising at least 16 field trips for the Apollo 15 crew, sandwiched between their already crowded flight training commitments. Scott admitted that after the enthusiastic Silver had finished with him, geological terms became part of his natural language.

Jim Irwin (left) with Dave Scott using a rangefinder that was never used on the Moon and Joe Allen on a geology training excursion.

Irwin, a good test pilot himself, admired Scott’s abilities and never competed with his Commander when it came to flying with him. Scott agrees that his LM pilot was probably one of the few people that could fit in comfortably with his autocratic style of command. As well as being friends, they made a good team on the lunar surface.

The geologists were also looking forward to the first lunar mission commander sympathetic to their cause – Scott’s enthusiasm for geology grew into almost total commitment – even insisting his wife take a geology course so she could understand what he was talking about.

The Apollo 15 crew were looking forward to making it the best mission of all, and the first to concentrate on the scientific aspects of the Apollo lunar visits.

The landing site

After proposals from all the working groups involved were sifted through, the Apollo Site Selection Board narrowed the choice of a landing site down to two areas – the Marius Hills with its possible rare volcanic rocks, or Hadley/Apennines, where the steep western scarp of the Apennines faced the basin with vertical sections of rock beds with one of the larger sinuous rilles on the Moon, and a patch of mare to explore and hopefully provide samples of primordial rocks.

At a convention in Houston on 24 September 1970 the rugged Hadley site came out on top. It is situated on the edge of the vast Mare Imbrium, the Sea of Rains, next to one of the Moon’s great mountain ranges, the Apennines rising 4.5 kilometres above the mare. This site was easily the most daring landing so far, promising spectacular scenery, and to the geologists, a chance of finding primordial material. It offered four major types of lunar features; a mare; an alpine range; a deep winding gorge; and a variety of smaller craters and soil types.

Hadley/Apennine looked set to provide a rich harvest for the geologists.

At Honeysuckle Creek

Operations Supervisor at Honeysuckle Creek, John Saxon:

“We almost completely rebuilt the station between Apollo 14 and Apollo 15, working masses of overtime so much so that some people begged for a break. The difference between 14 and 15 was almost like a new project. There were a whole new lot of communications with scientific experiments in the Service Module, there was a Particle and Fields sub satellite which was ejected from the Service Module into orbit around the moon, there was a lunar rover vehicle which they drove around on the surface of the moon.

The communications were becoming horrendous – there were so many links involved back packs of the astronauts, the relay from the lunar rover, the LM, the Particle and Fields Satellite... we went into the mission not sure we could handle all this.

This diagram – of communication requirements during the Apollo 15 mission – gives an idea of the complex configurations needed at Honeysuckle. Illustration by Hamish Lindsay.

Again we had the lion’s share of that mission – we had all the excursions on the surface of the moon, the bringing up of the first lunar rover down link to the ground, all the critical parts of that mission we were prime.

Although we went into the mission with quite a bit of trepidation, it was quite amazing, it all went by the book it was perfect. Apollo 15 was the scientific and technical peak of our operations as far as I was concerned.”

Before the Apollo 15 mission the data end of the station was pulled apart and completely modified to accomodate the new more complex scientific J missions with the Lunar Rover. Here (L-R) Laurie Turner from the Telemetry Section discusses the new cable installation with Col Power of the Communications Section and Geoff Day. Photo and notes: Hamish Lindsay.

Our 12-hour shift change-over times varied from 0400–1630 to 0600–1830 during the mission period. I had my usual position of Tracking 1 in the USB section and drew the night shift under Mike Evenett on the Ops Console.

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THE MISSION

In the following tables these official acronyms are used:

All times and dates in tables below are Australian Eastern Standard Time (AEST, GMT +10), unless otherwise indicated. Change of day is midnight HSK time.

Spacecraft to ground voice exchanges indicated by italics.

The dark, windowless bedrooms on the third floor in the crew quarters at Cape Kennedy were silent except for the sound of snoring. Dave Scott, Jim Irwin (the snorers) and Al Worden were dead to the world. Then suddenly at 0430 local time (USEDT), the somnific peace was rent asunder as doors were flung open and Deke Slayton’s gruff voice jolted the sleeping astronauts awake with, “Okay guys, this is it!”

Reality hit the crew of Apollo 15 when they had to face Dr Jack Teagen for a medical check before moving along to the dining room for the traditional breakfast of steak (plus scrambled eggs). With all those relentless hours of simulations and training behind them they were now really bound for the Moon. From this moment their every move would be dictated by the clock as they entered the Clean Room and suited up, followed by three hours of breathing pure oxygen to expel all the nitrogen out of their blood stream. Irwin had a towel put over his helmet to dull the light and tried to rest and sleep. They were all tired from the emotional events and farewells of the days before.

Apollo 15 crew at breakfast of steak and scrambled eggs on the morning of departure – from left Al Worden, Dave Scott, Deke Slayton, and back-up LM Pilot Harrison Schmitt.

At 0630 they set off for the launch area in the Transfer Van. Slayton said goodbye to them at Launch Control and their suit technicians accompanied them out to the Launch Umbilical Tower (LUT) where they were whisked 110 metres up to the White Room enveloping the Command Module at the top of the Saturn V. Scott climbed in the hatch first followed by Irwin and Worden. Karl Henize, one of the support crew, helped them settle in and the hatch clanged shut to seal them off from the world. Now their only communication was through their intercomm headsets.

By 0700, two and a half hours before launch, they were ready. Outside the weather was fine, with feathery cirrus clouds streaking the sky, while on the ground the temperature was 29.8°C. A 10 knot south south easterly breeze ruffled the sparkling waters around the launch pad. It was a perfect summer’s day.

Launch

At last the three astronauts heard the word “Ignition” in their headsets and at 2334 AEST (0934 USEDT) on Monday 26 July 1971 Apollo 15 left Pad 39A, and 11 minutes 44 seconds later entered a 91.5 by 89.6 nautical mile Earth orbit. As they entered orbit the astronauts had a view of the full Moon sitting right in the middle of the Command Module’s windows.

Apollo 15 Lift-off from Cape Kennedy – next stop, Hadley Base on the Moon.

At Honeysuckle Creek we never saw either Earth orbit due to a launch azimuth of 86°.

As usual, Carnarvon saw both, the second going right over the top of the station, and the ‘Go for the Moon’ was passed up through them at 0204 AEST on 27 July.

A 5 minute 56 second TLI burn was executed over Hawaii on time at 0224:02 AEST and Apollo 15 was on its way to the Moon. On the ground at Honeysuckle Creek we didn’t pick up the spacecraft until 8 hours 36 minutes after TLI. By that time the LM extraction manoeuvre had been performed, the Saturn IVB had been cast off, and the Passive Thermal Control (PTC) roll had been initiated.

It was 2300 spacecraft time (1400 AEST 29 July) before their day ended, a late night for the astronauts as they had been up since 0530, but before turning in they had to add chlorine to the water to stop bacterial growth, change the lithium hydroxide cartridges to keep the oxygen purified, and put up the metal window shades to block out the sunlight. They found the best way to get a restful sleep was for Worden and Scott to use their own outer couches while Irwin set himself up in a combined sleeping bag/hammock in the space under Scott, which gave them all more elbow room. They each took a turn wearing a headset so that they would be ready for a call from Houston.

We should note here that Carnarvon’s FPQ6 radar tracked the IU for a record distance of 131,400 kilometres.

Life aboard the Apollo spacecraft was different to our routines on Earth, even for the simple daily chores like eating. First they had to find the meal for that particular time of that particular day from the stowage map. All the food containers were labelled A, B, C, D, E, and all meals were colour coded. Scott’s were red, Irwin’s were blue and Worden’s were white.

Irwin commented, “So if a meal floated by and you identified it as being red, you could say, ’Hey, Dave, you’ve just lost your entree.’”

The meals came in a package the size of a large cereal box with six plastic bags containing the dehydrated food. They used a water gun to mix the packaged food with hot or cold water and had to wait 10 minutes for it to mix. Supplied by a restaurant, the freeze-dried and packed gourmet soups such as lobster bisque, crab, vichyssoise and romaine were the most popular food with the astronauts. Meats such as ham, turkey, and steak were packed in aluminium, but when they opened the packet the gravy slid out in blobs and floated around the cabin. To keep track of things they had Velcro all over the spacecraft and on the meal packages. With no dining table they would stick their dinner on the cabin wall in course order, then after eating they had to log down everything they ate, or didn’t eat, and advise Houston, who kept track of their energy levels.

Bathing was another chore. They dampened a washcloth and cleaned themselves all over as best they could. Only Irwin remembered to take along his own scented soap, “It was the high point of the day just to take out the soap from the container and let the scent waft around the spacecraft. It almost made us feel clean.”

During their evening, at 0930 AEST, Scott and Irwin decided to enter the LM fifty minutes early to check it out, but when they opened the hatch they found the cabin had broken bits of glass floating around. It was from the face of a lunar landing range and range-rate tapemeter. This was dangerous as the tiny shards of glass could cause damage to the eyes or lungs, but there was also the worry the tapemeter may have been affected, as it was a critical instrument for their landing on the lunar surface. A tapemeter is a meter which displays its reading with a moving length of tape that unreels rather than a pointer or digital display.

They promptly shut the hatch to stop any particles drifting into the Command Module and switched the LM’s air conditioner on, hoping to draw all the floating pieces to the exhaust screen where they could mop them up with adhesive tape wrapped around their hands. During the checkout good voice and data communications were established through Goldstone, and a successful TV transmission showing views of the Command Module and LM interior was completed.

Later they tried using a vacuum cleaner from the CSM to suck glass particles from crevices and crannies. At Houston the engineers worked on the tapemeter to see if its operation had been affected, but it seemed to be working okay. Scott admitted, “That gave me a warm feeling to know that they checked the thing out and it would work with a broken outer pane of glass.”

At 0311 AEST the astronauts tried the first scientific experiment of the trip, the Visual Light Flash Phenomenon by putting shades over the windows and their eyes and looking for strange orange flashes in their heads reported from earlier flights. They reported seeing 61 flashes, sometimes all three astronauts would see the same flash. “They look like flashbulbs popping in a darkened arena,” commented Scott. They are believed to be high-energy cosmic rays impacting the eye’s retina, or perhaps the brain’s optical centre. The experiment was repeated later in the mission.

During the ‘late afternoon,’ at 1734 spacecraft time (0834 AEST), Scott and Irwin checked out the LM for about two hours, and collected about 60% of the broken glass. Everything checked out to specifications, including the tapemeter.

Endeavour’s water leak

When Irwin went to chlorinate the water during their ‘evening’ at 1245 AEST he found quite a lot of water had started to weep out of the inlet fitting. Scott saw this as a serious situation – with no water, there would be no equipment cooling, which meant many critical CSM systems would be disabled, jeopardising their return to Earth.

Scott, “Okay, we’re just getting ready to do some chlorination here, and we find we’ve got a leak around the chlorine port – with a cap on it –seems to be leaking water. And you might take a look at that real quick and see if you can come up with any ideas on the thing. The cap is on and Jim was just getting ready to take the cap off and noticed a little water; and, in trying to clean it up, it seems like we’re accumulating a fair size – fair amount of water right now, right around the cap.”
Henize, “Can you give an – give us an estimate of how many drips per second it is?”
Irwin,” Yes, it’s a – it’s a pretty good flow right now. Drips per second, it’s hard to measure; it’s a whole ball of water right around that valve right now.”

The astronauts tried to explain, water doesn’t drip out in space it just makes a blob, and the blob keeps getting larger and larger. Looking for towels to mop up Irwin found, “Wouldn’t you know, about that time the locker door with all the towels in it jammed!” So while Scott was trying to stem the water flow, Irwin and Worden were trying to open the towel locker. Houston insisted on trying to estimate the flow rate, but soon Henize advised: "Okay, stand by. Lots of people are thinking down here now."

Then, "We suspect the injector outlet is loose. We need tool number three (a hexagonal Allen key) and tool number W (an extension ratchet) out of the tool kit."
Scott: "Okay, three and “W” out of the tool kit."
Heinz: "Right, put... put number three in the tool W ratchet and insert tool three in the hex opening in the chlorinator injector port."

Scott tightened the valve and the flow stopped. "Yeah. All we have to do now is hang out a few towels to dry, but it looks like we’re in good shape,” he announced as they mopped up a litre of water clinging to the valve as a blob.

When they had finished at 1304 AEST there were wet cloths strung all over the lower equipment bay and up into the LM tunnel, reminding the crew of an old fashioned clothesline.

Henize called back, “Incidentally, Dick (Gordon) was over at Lurton’s (Scott’s wife) and they called up to say "Hey, it’s about time you take a bath up there."
Scott, “Well, we were sort of discussing that a little earlier tonight anyway. And, as a result, well, I guess we all got cleaned up.”
Scott, “And our trusty LMP (Irwin) came up with an interesting analogy relative to the last event. He wondered if the original Endeavour had ever sprung a leak like that?”
Henize, “Okay; that’s a good question. We’ll get our historians out to check that one.”

That query eventually ended up with us at Honeysuckle Creek via Net 2 on 2 August.

While the astronauts were asleep that ‘night’ they crossed the equigravisphere at 1529:20 AEST to come under the Moon’s gravitational influence. They were now free falling ever faster down to the Moon.

The Department [of Supply] thought it would be a nice gesture to present something to commemorate the leaks of the two ‘Endeavours’ so the Station Admin Officer, Milton Turner, made up three posters of a copy of Cook’s log of the incident and my photograph of the station taken during Apollo 15 and Station Director Don Gray presented them to the astronauts on a visit to America. Here Dave Scott (left) and Alfred Worden (right) accept their posters from Don Gray. (Read more towards the end of Mission Day 7 and the start of Day 9.)

As Apollo 15 approached the Moon, sailing through its shadow, they could see it as a crescent through the windows of the Command Module. Scott noticed the dark side of the Moon facing away from the sun was aglow with Earthshine, brighter than moonlight on Earth. They could easily see the mountains and crater rims glowing from the reflected light from the Earth.

Lunar Orbit Insertion

They prepared for the LOI burn as the spacecraft coasted across the front of the Moon at a height of 543 kilometres and circled behind, when they lost contact with Goldstone.

Capcom Henize: “Gentlemen, everything looks perfect down here, and – all we can say is, "Have a good burn."
Scott: “Okay, thank you. We’ll see you on the other side”.
Henize: “Roger”.

After a 6 minute 32 second burn for Lunar Orbit Insertion (LOI) at 0629 AEST, Apollo 15 slowed down to 5,600 kilometres per hour and was safely in orbit around the Moon. All of a sudden they plunged out of the darkness into sunlight and Scott was enraptured by the moonscape 96 kilometres below them. He said, “That first far-side pass is a mindblower – hard to do much but just stare in awe!” With no atmosphere all the features and shadow edges were sharply defined and he couldn’t believe the Moon seemed so big. The first large feature they spotted was Tsiolkovsky Crater gliding past with its light coloured high central peak surrounded by its circular dark ‘sea.’

Scott: “...and I’ll tell you, it’s really spectacular, when you can see the central peak of Tsiolkovsky coming up over the horizon before you see the rim.”

Crater Tsiolkovsky on the far side of the Moon. Named after Konstantin Tsiolkovsky (1857–1935), the visionary deaf Russian school teacher who proposed so many space challenges such as Earth satellites, liquid fuel rockets, multiple stage rockets, space suits, closed life-cycle systems, and colonisation of space, with his famous quotation, “Earth is the cradle of the mind, but one cannot live in the cradle forever.” Approaching the crater (left) and passing over it (right).

It was the sunrises every two hours that impressed Scott the most, as he explains, “First of all these wispy streamers of light from the sun’s corona appeared above the lunar horizon, then the sun simply exploded over the horizon like a visual thunderclap, and within a second we were blinded by its bright light flooding the cabin.”

At 0630:19 AEST Goldstone and Madrid picked up the signal on the other side of the Moon:

Henize, “Fifteen, this is Houston. How do you read?”
Scott, “Hello, Houston, the Endeavour’s on station with cargo, and what a fantastic sight.”
Henize, “Beautiful news. Romantic, isn’t it?”
Scott, “Oh, this is really profound; I’ll tell you, fantastic!”

Alan Shepard and Pete Conrad were listening to the spacecraft communications as they prepared for a TV interview. Test pilot Shepard growled, “To hell with that shit, give us details of the burn.”

Unable to hear Shepard’s gripe, the crew began to describe the lurain they were flying over. Due to their higher latitude they were flying over scenery never seen before by the other missions.

By the time Honeysuckle Creek acquired Apollo 15 in parallel with Goldstone at 1103 AEST they were in orbit 3. For the next 2 hours the three astronauts were busy with engineering and experiments as well as bringing the SIM equipment to life, until they went to sleep at 1334 AEST. The spacecraft voice channels went quiet during orbits 4 to 8 as the astronauts slept.

Before separation they dropped into a 15 x 72 kilometre orbit.

As they zoomed low over the lunar surface, Irwin realised that there were mountains nearly as high as they were, for instance the Apennines reach almost a quarter of the spacecraft’s altitude so the sensation of speed is heightened by their closeness. “You look out on the horizon and you see these high peaks and you are just skimming along. Now you really know you are moving fast. You are travelling about 5,000 feet per second, that’s Mach 5, or 3,000 miles per hour (4,820 kph). Your orbit is defined; you can’t dodge anything. You don’t have control over the vehicle, and if you did you probably couldn’t react fast enough. You just assume that Houston knows where the mountains are and how high they are. But you see the high mountains on the horizon and you move towards them very fast. You wonder if you are going to clear them.”

Capcom Henize: “Fifteen – does it look like you are going to clear the mountain range ahead?”
Irwin, “Karl, we’ve all got our eyes closed; we’re pulling our feet up.”
Henize: “Open your eyes. That’s like going to the Grand Canyon and not looking!”

At around 0712 AEST the crew prepared for a scheduled 7.7 hour sleep period.

Irwin, “Houston, Fifteen. We are going to configure communications for sleep.”
Henize, “Fifteen, Houston. Could you hold off on that until just after LOS.”
Irwin, “Okay”.
Henize, “Okay, Fifteen. Our last worry seems to be cleared up down here. We’ve got nothing more to bother you with, and all we can do is wish you a good night’s sleep.”
Irwin, “Thank you, Karl. Good night”.
Henize, “Good night.”

For us, of course, it was 7:12 am of a new day. The Flight Controllers kept an eye on the astronauts and the spacecraft’s systems while the spacecraft was behind the Moon by recording all the data on the Data Storage Equipment (DSE), rewinding the tape, and playing it back it through us each time they reappeared.

We were the only station tracking when Houston woke them up nice and early at 0615 spacecraft time (2115 AEST) during orbit 8 to pass on flight plan updates, followed by a TV session of the Moon’s surface from orbit, including a preview of Hadley Rille and the Apennines.

At 0134 AEST Scott and Irwin began their transfer to the LM as the CSM began its eleventh orbit, and spent a complete orbit activating and checking Falcon’s systems. While out of contact with Earth, at precisely 0348:16 AEST Worden threw the switch to release the two spacecraft. “I guess the major thing is that everything was nominal, except when I went to Release on the probe Extend/Release switch; nothing happened. Nothing!!” said a baffled Worden.

In the LM Scott and Irwin looked at each other; they couldn’t figure out what was wrong. Scott then told Worden to check the LM/CSM umbilical electrical connections to the docking equipment. Within four minutes, in the middle of this crisis, they came from behind the Moon and locked onto Madrid’s signal. Capcom Edgar Mitchell called the spacecraft from across the Atlantic, “Endeavour, Houston. Standing by for a Sep report.”

Scott replied with the unexpected news, “Okay, Houston; this is the Falcon. We didn’t get a Sep, and Al’s been checking the umbilicals down on the probe.”

They had 40 minutes to find the problem before the flight plan would have to be attacked. Houston noticed a temperature reading off-scale high on the probe assembly, which indicated that there was no electrical power to the probe. One reason for this could be the umbilical was either not connected or not firmly plugged in. Worden removed the hatch and re-plugged the connectors – and all the readings in Houston settled back to normal.

David Scott training on opening the hatch in the docking tunnel between the Command Module and the Lunar Module.

CSM/LM Separation

Worden, “Okay, Falcon; this is Endeavour. And I’m all set up again. The tunnel’s sealed in and the pressure’s good.”
Worden, “Ten seconds.”
Scott, “Okay; we’re on the capture latches.”
Worden, “Good.”

At 0413 AEST the LM broke away from the CSM, just 13 minutes 56 seconds behind the flight plan scheduled time.

Irwin, “And you’re on your own.”
Scott, “Okay; good clean Sep.”

Scott and Irwin flew alongside Endeavour while Worden visually checked the LM was ready for landing with all its legs extended, before returning to a 120.2 by 100.6 kilometre orbit. The LM landing occurred 3 hours 32 minutes before our tracking day began – we were still going through our pre-pass SRT checks when they touched down.

The Hadley landing site viewed from orbit. Mount Hadley Delta and the Apennines can be seen at the lower left, the Rille and Trophy Point just above, the Rille leading to Mount Hadley towards the upper right. The North and South Clusters can also be seen in the middle of the valley.

The landing at Hadley was timed so that the Sun was just 12° above the horizon, giving oblique lighting with lots of shadows and aiding landmark identification during the final phase of the landing itself. Though the Sun was illuminating the mountain peaks around the landing site, it had yet to reach the surface of the plain at Hadley.

The Landing

Scott concentrated hard on bringing Falcon down to the final stages of this tricky landing, a target at the bottom of a basin hemmed in on three sides by mountains, and on the fourth by a deep gorge. At a height of 2,440 metres above the valley surface, they were flying horizontally, feet-first, looking straight up before pitching forward at 1,800 metres to be able to see where they were. Both astronauts were suddenly startled to see the white flank of a mountain sliding past above them out of the left window! It was Mount Hadley Delta soaring up 3,350 metres from the valley. The simulator had never shown them this – was Houston aware how close it was!? What if they had been off course? Scott looked as far forward as he could but still couldn’t see any sign of Hadley Rille: “I looked out the window and could see Mount Hadley Delta. We seemed to be floating across Hadley Delta and my impression at the time was that we were way long because I could see the mountain out the window and we were still probably 10,000 to 11,000 feet (3,048 metres) high. I couldn’t see the Rille out the forward corner of the window, which you could on the simulator – out the left forward corner.”

Mitchell, “Falcon Houston. We expect you may be a little south of the site....maybe.. ....3,000 feet.” This was due to a slight error that had developed in the LM’s flight path.

When Falcon pitched over on time all Scott saw was a featureless plain below them. He was looking for Index Crater, where they were supposed to land,

“I couldn’t convince myself that I saw Index Crater anywhere. I saw, as I remember, a couple of shadowed craters, but not nearly as many as we were accustomed to seeing in the simulator. Once I realised that we were not heading for the exact landing site, and I didn’t have a good location relative to Index Crater, I picked what I thought was a reasonably smooth area and headed directly for that.” Then in the distance ahead he could make out Hadley Rille, so he manually brought the LM down to where he thought the planned landing should be, “At about 60 feet (18 metres) the dust came up at us and I lost sight of everything and concentrated on Jim’s calls. I hoped there were no boulders or craters under us......... we were dropping blind – then Jim called “Contact” and I shut the motor off.”

Irwin, “The light came on. I called ’Contact!’ and Dave immediately pressed the button to shut the engine then we fell. We hit. We hit hard; I said ‘BAM!’ but it was reported in some of the press accounts as ‘damn.’ It was the hardest landing I had ever been in. Then we pitched up and rolled off to the side. It was a tremendous impact with a pitching and rolling motion. Everything rocked around and I thought all the gear was going to fall off. I was sure something was broken and we might have to go into one of those abort situations. If you pass 45 degrees and are still moving, you have to abort. If the LM turns over on its side, you can’t get back from the moon.”

Falcon landed on the lunar surface with the hardest of the Apollo landings at 2 metres/ second. Scott had by far the heaviest spacecraft to that date with the first Lunar Rover aboard. He was also very quick to switch the engine off, as he wanted to make sure the engine was off before the bell housing, which was longer than the earlier models, could contact the surface. “Okay, Houston. The Falcon is on the Plain at Hadley,” Scott advised Mission Control.

Irwin, “We just froze in position as we waited for the ground to look at all our systems. They had to tell us whether we had a STAY condition.”

As soon as they got the STAY order, the two astronauts pounded each other on the shoulder, celebrating their success, feeling real relief and gratitude, and started powering the LM down.

Falcon had landed at 0816 AEST on 31 July on the edge of Mare Imbrium, which stretched across the surface of the moon for at least 1,050 kilometres to the west. They were 548 metres to the north west of the planned landing spot. The LM had settled down straddled across the rim of a crater with a tilt back of 6.9° and a lean of 8.6° to the south. The descent engine bell had been damaged a bit, probably from pressure build up on landing and the rough lurain underneath.

SEVA – Stand-Up EVA

Two hours later, at 1016 AEST, (Goldstone were tracking, we were still 1 hour and 32 minutes from acquisition of the LM) Scott climbed up on the engine cover, opened the top hatch and gazed out on the lunarscape, the only pre-EVA reconnaissance conducted during the Apollo landings.

With all the simulations and study, plus his own imagination, he wasn’t prepared for the sight he now beheld. With the sun only 13° above the horizon the lofty Apennines to the south were heavily cloaked in shadows, their flanks glowing a pearly gold and brown in the early morning sunlight. Stark white craters scarred the soft beige of the flowing lurain. Scott commented, “Those are very, very big mountains, but they’re all rounded. The striking thing to me was that there are no sharp peaks.”

He tried to make out the footslopes of Hadley Delta and the routes they were to take in the Rover on Sunday and Monday – looking for outsize boulders or small ravines that might block their passage. Dark lines ran around the base of the mountains. Swinging his gaze to the south west he could clearly see St George crater scooped out of the side of Hadley Delta, their goal for tomorrow. He couldn’t make out any features that might prevent their progress. It looked good for excursions in the Rover.

Like a magnet his gaze was drawn up to the blue and white Earth glowing in the impossibly black sky the only colourful object in the whole scene before him. He spent thirty minutes just studying, photographing, and reporting his observations back to Mission Control in Houston. NASA Geophysicist Robin Brett said his descriptions were as good as a professional geologist, many agreeing it was the best geological description by an astronaut on the moon.

Scott: “The incredible variety of landforms in this restricted area (on the moon the horizon lies a scant mile and a half from the viewer) fills me with pleasant surprise. To the south an 11,000 foot (3,350 metre) ridge rises above the bleak plain. To the east stretch the hulking heights of an even higher summit. On the west a winding gorge plunges to depths of more than 1,000 feet (305 metres). Dominating the north eastern horizon, a great mountain (Mount Hadley) stands in noble splendour almost three miles above us.”

Feeling intruders in an eternal wilderness, they closed the hatch after 33 minutes, just before we acquired their signal. After re-pressurising the LM they continued observing the mountain through the window, trying to refine their exact location with Joe Allen in Houston. Nearly an hour later they turned in to sleep. It was an early lunar morning outside, late evening inside the spacecraft, and mid-morning the next day at Honeysuckle Creek. Trying to keep their day/night circadian cycle in synch with their home time zone on Earth, they prepared for a scheduled sleep period before setting out on the first EVA. They were the first astronauts to doff their spacesuits and sleep on the Moon in the comfort of their underwear.

Irwin, “Dave was sleeping fore and aft, and I was athwart ship, with my hammock slung under his. I noticed that my hammock was bowed out a little bit and my feet were sort of dangling off. It was noisy in the LM with the pumps and fans running, something like sleeping in a boiler room. But, man, it was comfortable sleeping! Those hammocks felt like waterbeds, and we were light as a feather. The first night’s sleep was the best I had the three nights we were there.”

At Honeysuckle Creek we acquired the spacecraft on moonrise at 1148 AEST with the crew just beginning a 7 hour sleep period, getting ready for the big events of the next day. The links were quiet with no TV or voice traffic while we just quietly tracked the LM’s signal from the lunar surface. The Wing was in a continuous cycle of AOS and LOS as the CSM circled the Moon, with Worden beginning a 7 hour sleep period on orbit 18 at 1155 AEST.

After a reasonably restful sleep the two astronauts in the LM began suiting up at 2147 AEST. Irwin noted that he and Scott had more conversation while helping each other suiting up than in all the previous couple of days. They had the hatch open by 2313 AEST, and we picked up live television from the camera in the MESA 13 minutes later, nicely in time to see Scott finish climbing down the ladder, followed by Irwin.

Scott announced,

“As I stand out here in the wonders of the unknown at Hadley, I sort of realise there’s a fundamental truth to our nature... man must explore, and this is exploration at its greatest.”

Commander David Scott descends Endeavour’s ladder and takes his first steps on the lunar surface. Frames grabbed from the Apollo 15 television broadcast by Colin Mackellar (with thanks to Mark Gray and Spacecraft Films and also to Bill Wood for colour correction.)

When Irwin reached the bottom and put his boot on the LM’s footpad it unexpectedly spun around, and he had to grip the ladder hard to stop himself from losing his balance and ignominiously falling down on his back. Mortified at the thought of tumbling over in front of the TV camera, he recovered, bounced onto the surface, kicking up a spray of black moondust. Then peering to the south, exclaimed: "Oh, boy, it’s beautiful out here. It reminds me of Sun Valley."

As Irwin had a special love of the exhilaration and wild remoteness of great mountain ranges on Earth, going right back to his youth, he was looking forward to the first exploration of these Mountains of the Moon. The Apennine Mountains almost looked familiar to him, rounded and treeless. He thought they looked like promising ski slopes.

After five days of being cooped up in the spacecraft, both astronauts felt the relief and pleasure of being able to move around again, the freedom of room to run in. They felt it was almost like walking on a trampoline, the same bouncy feeling, and falling down was quite different to Earth you seemed to go down in slow motion with only a light impact that they felt would never cause any harm.

At Honeysuckle Creek we crossed our local midnight into Sunday with the two astronauts setting up the Rover for the first excursion.

While Scott and Irwin were away Worden was endlessly orbiting the Moon, busy with a continuous stream of experiments, mainly operating the SIM bay equipment. To introduce some variety into the monotonous greetings each AOS every two hours, and to show a respect for other cultures, he thought it would be a good idea to use a different language for each “Hello Earth, Greetings from Endeavour.” So he sat down with Farouk El-Baz, a popular geologist working with the Apollo lunar program, and wrote down the phonetics for a number of languages and used them regularly as he appeared from behind the Moon.

Lunar Rover deployment

Just before our midnight, at 2352 AEST 31 July, the astronauts tugged the two "D" rings to release the $US40 million lunar rover and it fell out, assembling itself as it dropped – the chassis folded into position and the wheels flopped out. The astronauts only had to secure everything with locking pins and load up to be ready to travel – the assembling operation only taking 8 minutes.

The Apollo 15 Rover being fitted to the LM.

Dave Scott inspecting the mounting assembly.

After running through the checklist, Irwin stood by with the 16mm movie camera while Scott put the Rover through its paces with a display of his driving skills. The camera jammed so there are no movies of the first trials of the Rover, those had to wait for Apollo 16. There was also a slight hitch with the Rover’s steering, “I don’t have any front steering, Joe.” called Scott. After cycling the front steering switches a few times, "Still no forward steering, Joe." After physically trying to turn the wheels, they gave up, and initialised and calibrated the Rover’s navigation system before departing for the Elbow Crater excursion.

Luckily the front wheels were locked in the straight-ahead position.

The Apollo 15 traverses with Stations numbered. A pre-mission NASA diagram anotated by Hamish Lindsay.

The First Rover Excursion

As they set off for the first run at 0119 AEST, Scott said, “Okay, Jim, here we go.”
Irwin, “Okay, Dave. We want a heading of 203.”
Scott, “Okay, 203.”

Unfortunately for us at Honeysuckle Creek the Moon sank below our horizon at 0130 AEST just as Scott and Irwin were setting out. We only saw 12 minutes of the first excursion, so we missed all the excitement and spectacular scenery of St George Crater. All the action was now going on through Madrid as our equipment fell silent and the TV screens went blank. We then had to listen to the rest of the excursion’s progress on Net 1 as we went through the post pass procedures, feeling a bit left out, especially with no TV.

As the explorers headed south west Scott relayed his experiences:

"The steering is quite responsive even with only the rear steering. It does quite well. There doesn’t seem to be too much slip. I can manoeuvre pretty well with the thing. If I need to make a turn sharply, why, it responds quite well. There’s no accumulation of dirt in the wire wheels.”

"Just like the owner’s manual," responded Allen.

Although the Rover only travelled at around 11 kilometres per hour, the two astronauts found they often became airborne as it flew over the lurain with a pitching motion rather like a cross between a boat in a lumpy sea and riding a horse. One of the fears had been that as the Rover sped across the surface it would vanish into a cloud of dust thick enough to block the astronauts’ view to see anything. Luckily this didn’t happen, the wheel fenders doing their job as designed. Scott noticed their wheels cut chevron-patterned tracks to a consistent depth of about 2 centimetres in the lunar soil.

Getting to sit on the Rover seat in a stiff pressure suit from the lurain was not so easy. The astronauts found they had to stand facing forward, then with an upward and sideways kick, jump up with their legs and arms stretched out ahead to hopefully land in the middle of their seat. Although a chore strapping them on, both astronauts were glad to be wearing seat belts as the vehicle rolled through hummocky craters and bounced over small boulders and fragments scattered along the way. With the one sixth g they often felt themselves floating in their seats, only held down by their seat belts. Scott frequently called out “Hang on” as the Rover hurdled yet another obstruction. The Rover’s suspension system reacted more slowly in the weaker lunar gravity, emphasising the wavy ride. Scott found they had to keep up a good speed to meet the planned activity schedules.

As Scott was the driver, sitting in the left seat, holding a “T” bar in his right hand, tilted slightly towards him to lessen fatigue. The bar gave full control of the Rover pulled to the left turns all four wheels for a left turn, right for right turn, pushing forward drives the vehicle forward, and pulling back can stop it in its own length. A switch on the base puts the Rover in reverse, with speed controlled by pulling the T bar back. As it didn’t have a rear view mirror, the astronauts sometimes preferred to just pick it up to turn it around as it only weighed 36 kilograms on the moon.

Power was provided by a 1/4 horsepower dc electric motor with a 80:1 reduction gear on each wheel, supplied by two 36 volt batteries with silver zinc plates in potassium hydroxide with the capacity to last twice the planned distances.

The Rover’s driving stick and instrument panel.

Though the Rover had quite sophisticated navigation facilities, in the beginning they had some trouble locating their position, partly because they weren’t sure of the exact location of the LM. Also, their photographic maps did not always translate into what they could see around them.

By now the sun had risen to 20° above the horizon, and the shadows were shortening. Apart from learning to drive the Rover on its first outing, Scott wrestled with trying to keep the speed up, avoid obstructions in their path, and absorb the spectacular scenery – all at the same time. He found it was difficult to take his eyes off where they were going, even for a second, so Irwin called the instrument readings. Because of all these distractions Scott felt they were travelling much faster than 10 kilometres per hour, “I think we could motor right on through the craters. The fresh ones with all the debris we might have gone around.” As they breasted a rise they were suddenly confronted with a deep crater, and Scott had to swing hard left, turning the Rover on two wheels. They both feared it might flip over, pinning them underneath, but thankfully it bounced back on its wheels.

Hadley Rille

Irwin, “Hey, you can see the Rille! There’s the Rille.”
Scott echoed, “......there’s the Rille.”

They raced on to arrive at the edge of the chasm and turned to follow it southwards, steering a course of 165°, heading for Elbow Crater. Scott found it was smoother driving along a ridge about 80 metres back and parallel with the Rille edge. Looking ahead they could make out Elbow Crater – though it looked quite close, when they drove there they found it was still a good distance away. On the Moon they were finding everything appeared closer than it really is.

Scott scanned the lower slopes of Mount Hadley Delta, “Yeah, we’re in good shape. We can see Elbow, and we can see the Front all the way down to the Spur (Crater). And, there’s not a big block on it.”

On their right the lurain sloped down 360 metres to the bottom of the Rille on their side, but on the opposite side, about 1.6 kilometres away, it fell with steep cliffs, strewn with boulders.

Looking for signs of layering on the opposite bank Scott commented, “There are lots of outcrops. But, on the far side, I don’t see anything that would suggest really layering. There’s a lot of debris, big angular blocks all the way down, but nothing that you’d really call exact layers.”

Irwin, “ I can see the bottom of the Rille. It’s very smooth. I see two very large boulders that are right on the surface, there – on the top of the very smooth portion, of the bottom of the Rille. And the one to southeast, I can see the track of where it’s rolled downslope.”
Allen, “Roger, Jim. Copy. And is the bottom V-shaped or fairly flat?”
Irwin, “I’d say it’s flat. Well, it’s hard to estimate. I’d estimate maybe, oh, 200 metres wide of a flat area in the bottom.”
Scott said, “I might add to Jim’s comment, that the near side of the Rille wall is smooth without any outcrops, there by St. George, and the far side has got all sorts of debris. It almost looks like we could drive down in on this side, doesn’t it?” he added mischievously, looking about for a possible spot to start a descent.
Allen, “Stand by on that, Dave.”

Irwin was much more cautious – he felt he could not face the furore if they lost the Rover on the bottom of the Rille. If Scott wanted to go, Irwin wasn’t going to go with him, so he firmly said, “I’m sure we could drive down; I don’t think we could drive back out.”

Elbow Crater

They arrived at the southern lip of Elbow Crater to stop at Station 1 at 0144 AEST for samples, and to relay information back to a group of geologists in the Science Operations Room across the hall from Mission Control. At this point they had travelled 4.5 kilometres and were 3.2 kilometres from the LM.

The television was the sharpest yet seen from the Moon and the geologists were living every moment of the astronauts’ experiences. The TV camera on the Rover followed their every move, controlled by Captain Video, Ed Fendell, sitting at his console in Mission Control.

Captain Video, Ed Fendell, (left) and Granvil Pennington get ready for another session driving the Apollo 15 Rover camera from their console in the Mission Operations Control Room. Fendell was the Capcom at Carnarvon for the Gemini IV mission with Dave Scott as the astronaut attached to his flight control team.

The Rover was proving its worth – there they were, quickly and effortlessly over 3 kilometres from the LM with plenty of consumables still to go and not at all tired. Unable to resist sneaking glances at the spectacular views around him while he worked, Scott raised his hammer on a knee-high boulder to chip a piece off it before rolling it over and taking samples from under it.

Exuberantly he relayed his feelings to the gang at Houston, “Yeah, man! I wish we could just sit down and play with the rocks for a while. Look at these things! They’re shiny! And sparkly! ............. Look at all these babies here; gosh, man!”

After 12 minutes at Elbow they proceeded up the slopes of Mount Hadley Delta for another eleven minutes, climbing steeply, much more steeply than expected, towards St George Crater, the Rover slowing down to 7 kilometres per hour.

Scott, “Okay; we’re going to a big block here, Joe. It’s one we just can’t afford to miss. Wanted us to look at a big block; we’re going to look at a big block. It’s the only big block I see anywhere.”
Scott and Irwin looked back, “........ Hang on. Hang on. Digging in. ................ Okay. Boy, this’ll give them a view. Oh my!”
Irwin, “Yeah, look that...What a view back into the Rille.”
Scott, “Ohhh! There’s almost a view right into that crater.”
Irwin with relief, “Glad you stopped short of it!”

Looking back down the valley they were surprised at how high they had climbed, and were awestruck by the stark, stupendous scenery spread out before them. It was a panoramic moonscape with Hadley Rille winding away from their feet to disappear into the foot of Mount Hadley in the distance. The Rill’s eastern walls were veiled in deep shadows, while parts of the floor and western cliffs glowed in the early morning sunlight. From above, the featureless jet-black sky reached down to the horizon. Behind them, the lurain sloped up to the deep basin of St George Crater, though the crater itself was out of sight from their angle.

They couldn’t see the LM, but checking their instrument panel they found it was bearing 17° at a distance of 3.9 kilometres and the speedometer reading was 5.5 kilometres. They climbed down from the Rover to sink into a soft powdery dust. It was the first time any astronauts had experienced trying to walk through such a steep, deep powder and they found the going tough. They were both soon breathing heavily from the exertion.

They set up the TV before inspecting the metre-sized rock. It appeared to be breccia on top of crystalline rock, with lots of vesicles, or imprints of gas bubbles, and coated with glass beads. As his boss wielded the geologist’s hammer, Irwin dug shallow trenches and collected samples and fragments for his bag.

Irwin’s trench.

In the end St George did not provide the hoped-for key to the mountains – there didn’t seem to be an ejecta blanket, rocks were rare and samples turned out to be breccias (fragments of older material formed into a coarse-grained rock) that contained more mare basalt than terra rock. They did not continue on to the big St George Crater, named after the bottle of Nuits-St-Georges that was drunk on the way to the Moon in Jules Verne’s epic, From the Earth to the Moon.

With time running out and their limited consumables, Houston decided to drop Station 3 due to these constraints and the less than enthusiastic observations of the area by the astronauts.

Allen, “Roger, Dave. And we’re interested in your climbing aboard now and start back towards the LM. We’re going to eliminate Station 3.”
Scott, “Okay.”

They jumped on board the Rover for the trip back home at 0302 AEST. On the way back while still near Elbow Crater they unexpectedly spun around 180° and stopped facing back uphill. It happened so quickly there wasn’t time to do anything about it. The astronauts were so taken by surprise they laughed uproariously.

Scott, “Hang on. Whoa! Hang on! Got to go easy downhill, huh?”
Irwin, still chuckling with Scott, “I’d say so!”
Scott, “You just...You can’t go fast downhill in this thing, because if you try and turn with the front wheels locked up like that, they dig in and the rear end breaks away, and around you go. And we just did a 180.”

By the time they were back passing Station 1 they could see the LM again. It was comforting to see their home base and the vehicle waiting to take them back to Earth. It was the first time any lunar astronauts had been out of sight of the LM.

As they were driving along Scott spotted a piece of basalt that looked different to anything around it and decided to pick it up for the collection. It was sitting out there, all by itself with no other fragments around. Very vesicular; very black and rounded. Scott felt, “That one, I could not pass up. It was just too different.” Knowing Houston would not agree to their stopping to pick it up, they pretended they were having trouble with their seatbelts, when in actual fact Scott had stopped the Rover to pick up the sample. It was a scoriaceous basalt with lots and lots of vesicles, or bubbles, and was nicknamed the ‘seatbelt basalt.’

By the time they arrived back at the LM at 0333 AEST they had been away for 2 hours 15 minutes and driven a distance of 10.3 kilometres.

Setting out ALSEP and drilling cores

While Irwin set out the ALSEP science experiments 125 metres west north west of the LM, Scott reeled out the heat probe cables and began to drill two holes for them and a 3 metre deep core sample. He was soon in trouble. With the first hole the drill bit jammed about 170 centimetres into the surface when Scott felt he had hit hard rock. Although he wasn’t aware of it at the time, the drill flutes were clogging due to a faulty design and the whole drill simply jammed tight in the hole. With time running away, Houston decided the hole was deep enough and told Scott to insert the heat probe. Scott then extracted the drill bit using a vice, and began on the second hole, but again the drill bit jammed at the same depth. Already six hours into the EVA, there was only thirty minutes of Scott’s oxygen left. Houston decided to leave the remaining drilling for tomorrow.

Meanwhile, with only minor troubles, Irwin had finished setting out the ALSEP equipment, and had it up and running by 0452 AEST, when the first signals were received by Madrid.

The two astronauts drove the Rover back to the LM a tired Irwin clambered up the ladder to load the lunar samples into the spacecraft. When Houston told him to rest, Scott wanted to use his time left, so Houston suggested he set up the solar wind experiment, scheduled to be done by Irwin the next day.

This is the last picture Scott took at the end of EVA-1. He is standing in the shadow of the LM looking north east towards 4.5 kilometre high Mount Hadley. With the sun still only 20° above the horizon, the long black shadows add a feeling of dramatic mystery to the scene. The camera and high-gain antenna are in their stowed positions, with some of the geology tool handles sticking up at the back of the Rover.

Calling to Irwin to talk him through the procedure from inside the spacecraft, Scott set about assembling the equipment about 15 metres from the LM. After pushing the mounting pole into the lurain without any trouble, he joined Irwin in the LM and re-pressurised the cabin at 0546 AEST.

Once they were all inside, they found the cabin of the LM became covered with graphite-like dust from the suits and samples. Once settled down the two astronauts discussed with Joe Allen the situation with the drilling and their exact location for almost two hours. After the first day’s activities both astronauts were totally exhausted, both suffering unbearable pain in their fingers from working with the gloves that had to be physically held closed against the internal pressure. With fingernails a little too long, the constant pressure on the fingertips separated the nails from the quick and made their hands excruciatingly painful. Harrison Schmitt from Apollo 17 likened it to squeezing a tennis ball repetitively for nine hours. Irwin cut his nails right back, but Scott elected to suffer the pain. Some of his fingernails turned black before they returned to Earth.

When they took their gloves off the perspiration poured out, showing they had lost a lot of body fluid with their hard work. Irwin had been unable to get to his suit drink waterbag to release its contents, so never managed a drink during the whole excursion. He felt very tired and was suffering a raging headache from the day’s exertions and lack of fluids, “We really guzzled down the water that night. I had been seven hours without a drink and sweating like a jogger.”

At Honeysuckle Creek we began our pass for the day when the Moon rose during our lunchtime at 1217 AEST with the astronauts asleep in the LM until they were woken up at 1730 AEST and after an eat period began to prepare for the day’s excursion. The first task given by Houston was to go find a suspected leak as the LM had lost 11 kilograms of water since the day before. Capcom Charles Fullerton suggested it might be behind the ascent engine cover because of the angle of the LM. They found 11 litres of water so they sco