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[Spaceflight History Blog] Log of a Moon Expedition (1969)
« dnia: Kwiecień 12, 2018, 07:58 »
Log of a Moon Expedition (1969)
10 April 2018 David S. F. Portree


Luděk Pešek's lunar expedition was intended to alight in Sinus Medii, a relatively flat region NASA would in fact select as an alternate landing site for early Apollo missions. In his book, Pešek generated drama by landing his eight-man crew off-course in rugged, unstable terrain between Reaumur and Flammarion. Image credit: Defense Mapping Agency/U.S. Geological Survey

In the 1969-1973 period, the post-Apollo era of robotic planetary reconnaissance was only beginning. The National Geographic Society wanted to give its members a preview, so it turned to Luděk Pešek. Born in Czechoslovakia in 1919, Pešek was out of his home country when Warsaw Pact tanks crushed the 1968 Prague Spring. Rather than return home to tyranny, he took up residence in Switzerland and became a Swiss citizen.

Luděk Pešek's photorealistic paintings of planets and moons dominated the August 1970 and February 1973 issues of National Geographic magazine. The 1970 magazine took in the entire Solar System. It bore on its cover Pešek's painting of Saturn as seen from its moon Titan. The 1973 issue celebrated the discoveries scientists had made using cameras on the Mars probe Mariner 9, the first spacecraft to orbit another planet. The magazine included as a special supplement an airbrushed map of Mars based on images from Mariner 9 and Earth-based telescopes. The map's reverse side featured Pešek's impression of the surface of Mars during a dust storm. It was probably the last great artistic rendering of Mars's surface before Viking 1, the first successful automated Mars lander, touched down in Chryse Planitia on 20 July 1976.

In 1964, as the real-life Moon Race between the Soviet Union and the United States gathered pace, Pešek had written a short novel about a lunar expedition. It was published first in the Federal Republic of Germany (West Germany) in 1967, then in the United States as Log of a Moon Expedition in 1969, a few months before the Apollo 11 Lunar Module Eagle became the first manned spacecraft to land on the moon.

Pešek's account now reads like alternate history. In some respects, his expedition plan resembles the Lunar Surface Rendezvous (LSR) Apollo mission mode the Jet Propulsion Laboratory (JPL) proposed in 1961-1962. LSR aimed to accomplish the Apollo manned moon landing using technology derived from the planned automated Surveyor soft-lander.

In JPL's LSR scenario, several automated landers would touch down on the Moon before any humans arrived. The first lander to reach the site would carry scientific instruments, a TV camera, and a homing beacon. After engineers and scientists used its data to certify the site as safe for further landings, other Surveyor-derived landers would touch down nearby. Their combined cargo would amount to three or four solid-propellant rocket motors, a robot rover with a mechanical arm, and an unmanned crew capsule with space for up to three astronauts, an Earth-atmosphere reentry heat shield, and parachutes. Controllers on Earth would guide the rover as it collected each rocket motor in turn and attached it to the lander bearing the crew capsule.

After JPL's lander/crew capsule combination was ready, an identical crew capsule on a Surveyor-derived lander would depart Earth bearing up to three astronauts. With help from homing beacons on the robot landers, it would slow its descent by firing solid-propellant rocket motors identical to those attached to the lander/crew capsule on the Moon. The astronauts would then transfer to the waiting lander/crew capsule and ignite its solid-propellant rocket motors to begin their return to Earth. Nearing Earth, they would cast off the lander and spent rocket motors and position their capsule for reentry.

Although billed in the U.S. at the time of its publication as a book for children, it is hard to believe that Log of a Moon Expedition earned much affection from that hard-to-please audience. This might account for the fact that it is not well known today. Pešek's tale reads like a technical paper told through a first-person narrator. Though fiction, its many technical details make it fair game for discussion in this blog.

Pešek's lunar program began with several years of hardware development and testing and at least four precursor lunar flights. An automated sample-returner collected rock samples at the proposed landing site and returned them to Earth for engineering analysis. Meanwhile, at least one automated spacecraft and at least two piloted expeditions (designated KM I and KM II) imaged the Moon's surface from lunar orbit.

Pešek considered the first piloted Moon landing to be the first step in Project Alpha, the intensive exploration of the entire Solar System by astronauts. He did not specify which country or consortium would carry out Project Alpha, nor did he provide a location for "Earth Control," the equivalent of NASA's Mission Control Center in Houston, ESA's European Space Operations Centre in Darmstadt, or the Flight Control Center near Moscow.


Spacecraft KM III. Image credit: Luděk Pešek/Alfred A. Knopf, Jr.

Pešek dispatched his lunar spacecraft, which he dubbed KM III, to Sinus Medii (Central Bay), a patch of relatively smooth, relatively flat mare ("sea") terrain at the center of the Moon's Earth-facing Nearside hemisphere. KM III was streamlined, with tail fins, short wings, a pointed nose, and at least one tail-mounted chemical-propellant rocket engine. Its pressurized cabin housed padded "anti-gravity" (acceleration) couches for eight men, an airlock, a radio/meteoroid-monitoring radar station, and an impressive array of stores and equipment, including at least 16 180-pound steel-shelled space suits (two for each expedition member). KM III was designed to land upright, with its nose pointed at the black lunar sky, on "stilts" that extended from its tail fins.

Before KM III left Earth, three automated cargo landers landed in Sinus Medii. Designated S 1, S 2, and S 3, they set down in a triangular pattern about 15 miles wide. Fat drums about 45 feet tall with silver-and-gray dome-shaped tops, the cargo landers each contained scientific equipment, tools, sturdy electricity-powered tractors for lunar surface transport, construction materials, a pressurized living volume stocked with air, water, and food, and, most important, a 40 tons of Earth-return propellant for KM III, which would land on the Moon with nearly dry tanks. Forty tons of propellant was sufficient to launch KM III off the Moon and place it on course for Earth.


Cargo lander S2. Image credit: Luděk Pešek/Alfred A. Knopf, Jr.

The expedition was planned to last eight Earth days. KM III was meant to land at the center of the S 1-S 2-S 3 triangle just after lunar dawn. Pešek wrote that the expedition included enough supplies to remain on the Moon for 14 Earth days (about one lunar daylight period), but that it could not stay past lunar sunset.

This was because the landers and tractors drew electricity from batteries kept charged by dish-shaped solar concentrators. Silver dishes would focus sunlight onto a boiler containing a working fluid that would turn to gas, move through pipes to a turbine generator with would make electricity, pass through radiators to shed heat and return to liquid form, and then return to the boiler to begin the cycle again.

Pešek did not give his intrepid lunar explorers names. Instead, they had three-letter "shortwave radio" designations. CAP was the calm, stoic leader of the expedition, while DOC, the narrator, was the "documenter" and photographer. MEC was the wise-cracking mechanic and navigator, PHY the expedition doctor, and RNT the radio and TV engineer. The expedition included three scientists: GEO, a geologist; AST, an astrophysicist specializing in radiation; and SEL, a selenologist ("Moon scientist").


The lunar expedition crew wore cumbersome steel Moon suits. They were prone to inexplicable oxygen regulator malfunctions and featured awkward sanitary arrangements. The numeral "5" on this suit's backpack identifies its wearer as MEC. Image credit: Luděk Pešek/Alfred A. Knopf, Jr.

Murphy's Law ruled Pešek's lunar expedition. Trouble began even before KM III left Earth. The S 1, S 2, and S 3 landers formed a triangle as planned, but its center was about 20 miles south of the intended target zone. This placed it uncomfortably close to rocky, rifted terrain between the craters Reaumur and Flammarion. Despite this, Earth Control decided to launch KM III on schedule.

The explorers did not pilot their spacecraft during descent to the Moon: instead, they strapped into their couches so that they could withstand KM III's rapid deceleration. The spacecraft's guidance system locked automatically onto the cargo lander homing beacons and steered it to a landing.

At touchdown, KM III released a "natrium" (sodium) cloud that fluoresced in lunar dawn light, permitting Earth-based telescopic observers to confirm its location on the lunar surface. As they waited for the sodium cloud to disperse so that they could see outside, the explorers worried that they had landed off target. Their radio could not pick up the homing radio beacon from S 2 and S 3's signal was very weak. In addition, the ground was apparently less stable than expected: KM III had an alarming tendency to list to one side. The crew extended the landing stilt on that side slightly to keep their spacecraft level.

When the shadowy landscape around KM III became visible outside the viewports, the terrain was unfamiliar. No elevated surface features should have been visible, yet there was a 190-foot-tall hill a few hundred yards to the north and a taller ridge beyond that. They named the former Revelation Hill. As the gravity of their predicament became clear, they dubbed the latter Disappointment Ridge.

CAP and DOC donned their cumbersome armored Moon suits and took humankind's first small steps on another world. Pešek wrote that, when they shook hands outside KM III, they felt as though they were "congratulating mankind." They then inspected KM III's landing stilts. All were sunk into the rock more deeply than expected. The stilt on the side toward which their spacecraft listed was extended to half its total length.

Soon after CAP and DOC climbed back inside KM III, Earth Control confirmed that the same navigational error that had affected the cargo landers had caused their spacecraft to land at least 20 miles southwest of its target. This placed KM III entirely outside the triangle. S 3, most northerly of the three cargo landers, was out of reach at a distance of at least 35 miles.

In addition, obstacles blocked the way to all three landers. KM III had landed at a straight-line distance of about a 17 miles from S 1. A three-man sortie party consisting of DOC, RNT, and AST wandered at least 20 miles through a maze of small craters and rifts before turning back to KM III empty handed.

On the way home, the radio signal from KM III abruptly broke off and the party became lost. AST's oxygen system malfunctioned, so he became exhausted and had to be carried. They abandoned a large camera and other equipment. Fearing for the lives of his companions, AST begged to be left behind.

Fortunately, as the situation grew desperate, DOC spotted a signal flare on the horizon. On course once again, they soon resumed radio contact with KM III, where the main radio transmitter had been down for four hours.

S 2, just five miles away, was behind Disappointment Ridge on the far side of a jagged rift up to 65 feet wide and 150 feet deep. The rift, which began close to Reaumur crater, ran for many miles, often through rugged terrain, so could not be circumvented. S 2 was, nevertheless, the most easily accessible of the three pre-landed cargo landers.

Earth Control hurriedly dispatched two backup cargo landers designated S 4 and S 5. After flights lasting 70 hours, they alighted south of KM III, in terrain even more rugged and inhospitable.

By that point, the crew of KM III had abandoned all scientific exploration so that they could focus on saving themselves. Displaying his artistic bent, Pešek described the length and slow motion of the shadows on the lunar surface and the mood they created among the explorers. As the Sun sank toward the horizon and shadows lengthened, the expedition became a perilous race against time.

The explorers confronted and defeated one challenge after another, pushing themselves and their equipment to their limits. They first injected "oxycrete," a specially constituted lunar concrete, under the sinking landing stilt to stabilize KM III.

Next, they set up a 15-foot-diameter solar concentrator near the lander to charge their batteries. They also erected a 130-foot-tall radio relay tower atop Revelation Hill so that they could communicate with S 2.

Pešek's brave crew climbed and found a pass through Disappointment Ridge, then found places where they could enter the rift and, after traveling some distance along its rocky, shadowed floor, climb out on its far side with the aid of ropes. They marked their way using red metal disks mounted on poles. At last reaching S 2, they activated its living quarters and unloaded tractor TK 2.

They were plagued with Moon suit oxygen regulators that had functioned flawlessly in labs on Earth and in Earth orbit, but which failed inexplicably whenever they passed into cold shadow on the Moon. The curious malfunction was at first life-threatening - it allowed exhaled carbon dioxide to build up in the Moon suits, and probably accounted for AST's difficulties during the nightmarish trek home from S 1 - but through trial-and-error it become a mere persistent annoyance. AST and CAP suffered injuries that left them unfit to do heavy work, and all the men suffered rashes and sores from wearing their Moon suits for far longer than originally planned. As they hiked and labored for long hours, they were obligated to try to sleep in them.

DOC was part of the three-man team that reached S 5 on foot, a grueling hike through 10 miles of boulders and steep hillocks. They barely managed to unload tractor TK 5 before S 5 tilted on unsteady ground and toppled into an "abyss." Soon after their close brush with catastrophe, DOC called the Moon "a world of death" that could "not be underestimated for a minute."

Nevertheless, retrieval of TK 5 marked a turning point for the Moon explorers. Availability of TK 5 on the same side of the rift as KM III permitted the crew at last to devise a plan for refueling their spacecraft. They would load 650-pound, six-foot-long propellant tanks from S 2 onto TK 2 and transport them to the rift. The tanks would then be transferred to buckets hanging from an aerial tramway intended originally for unspecified selenological studies, and finally to TK 5 for the slow, slippery climb over Disappointment Ridge to KM III.

TK 2 and TK 5 could each carry up to 20 propellant tanks at a time, and the tramway buckets could move 20 tanks across the rift in one hour. Twenty tanks had a mass of about 6.5 tons, so about six trips were required to transfer from S 2 the 40 tons of propellants KM III needed to return to Earth.

The challenges did not end - TK 2 became stuck, meteoroids damaged KM III's solar concentrator, the aerial tramway nearly collapsed into the rift and had to be moved, and KM III began again to list to one side as propellants filled its tanks - yet Pešek's intrepid lunar explorers won through. With the glaring Sun touching the horizon and small features of the landscape casting long shadows, KM III lifted off with just hours to spare.

Sources

Log of a Moon Expedition, Luděk Pešek, Alfred A. Knopf Publishers, 1969

Man-to-the-Moon and Return Mission Utilizing Lunar-Surface Rendezvous, Technical Memorandum No. 33-53, P. Buwalda, W. Downhower, P. Eckman, E. Pounder, R. Rieder, and F. Sola, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, 3 August 1961

"Man-on-the-Moon and Return Mission Utilizing Lunar-Surface Rendezvous," J. Small & W. Downhower, Jet Propulsion Laboratory; paper presented at the American Rocket Society Lunar Missions Meeting Held in Cleveland, Ohio, 17-19 July 1962

Ludek Pesek: Space Artist (accessed 10 April 2018)

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Source: Log of a Moon Expedition (1969)

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[Spaceflight History Blog] Log of a Moon Expedition (1969)
« dnia: Kwiecień 12, 2018, 07:58 »