Boldly Going Part 26
Minerva 3’s month-long trip to the moon in 2001 would be the first demonstration of the Habitank concept in-situ on the lunar surface, extending the legacy of
Enterprise’s wet lab design to the moon. As a Class-B outpost mission, Minerva 3 required a total of
four Shuttle-C launches, with each pair being used to send a separate LSAM lander to the lunar surface. The first lander was pre-positioned in Tsiolkovsky Crater in the late summer of 2000. Freed from the need to carry an ascent vehicle, this vehicle - only the second LSAM to land on the lunar surface - carried another 16.5 metric tons of surface payload. Though also including various power systems and surface exploration gear, the primary payload was the massive Service Core, a lunar equivalent to
Enterprise’s node modules. The module offered an 8 meter long, 4.27m diameter core unit filled with consumables and life support systems. It was fitted to act as the nexus of the Class-B outpost while offering the potential to expand into a Class-C lunar base. To this end, it housed six deployable inflatable passageways, with one on each end and two along each side of the module. The side passageways were positioned so that when the core was positioned properly, the two inflatable passageways on a side of the module could be connected to ports on the end of the two Habitank modules on an LSAM, tying the core to the LSAM’s pressurized volume in two places. A second LSAM could then be attached on the other side, forming the Class-B configuration. In this “figure-8” layout, the outpost would consist of two airlocks (one on each LSAM), one sortie hab, the ascent module cabin, four Habitanks, and the core module--nine rooms totaling more than 1,200 square feet of floor space. Though called a “cabin,” even this early outpost would be a spacious base for exploration. The two end passages on a Lunar Core Module could be connected in series, allowing the expansion from the two-LSAM medium-duration outpost into a full lunar base of nearly arbitrary size.
The second major payload carried by Minerva 3B’s LSAM was one of the program’s most controversial decisions: the use of a nuclear reactor for outpost power generation, providing all the power a base could require through the two-week lunar night. The TOPAZ-II reactor would constitute the main Russian contribution to the lunar program, providing 5 kW of electrical power from just 12 kg of Uranium contained within the 1,000 kilogram reactor system. The political benefits of using a Soviet-derived nuclear reactor and avoiding Soviet space scientists and nuclear engineers seeking alternative employment was a powerful cudgel used to help overwhelm Congressional opposition to the application of nuclear power in space.The benefits of a powerful and consistent energy source for future outposts helped ensure its selection by NASA. However, even given the successful demonstration of TOPAZ-II for eight months on the lunar surface prior to the arrival of the Minerva 3 crew in 2001, opposition by anti-nuclear advocates was strong--though often mistaken, as the peak of protests came during the launch of the Minerva 3B mission on STS-127, when the reactor had already been delivered and operational on the lunar surface for more than eight months.
In an echo of the STS-38R
Enterprise commissioning flight, when the crew of Minerva 3 arrived on the lunar surface thanks to another pair of Shuttle-C launches in early 2001, their first task was the assembly of the outpost they would occupy, a project which would consume most of the six Earth days remaining before lunar night. Thus, bare hours after landing, the crew of Minerva 3 deployed the main cargo of their LSAM: four of the golf-cart-sized lunar rovers which were the utility vehicles of the Minerva surface architecture. Officially the Multi-Utility Lunar Exploration System, these “mules” were the packbeasts of the Minerva architecture. Each had four wheels: two large 1.5m diameter forward wheels, and two smaller trailing wheels, with steering somewhat like a tricycle provided by a hinge between the front axle and the main chassis. Two “mules” could be coupled together, providing supplemental carrying capacity and redundant batteries and motors in the event of any failure. This redundancy was key to allow a more safety-conscious NASA to qualify the system for extended traverses well beyond walk-back distance. A single mule pair could carry the entire expedition, and thus a full-crew traverse was protected against the complete failure of even two of their four mule prime movers. The mule’s awkward wheel arrangement was a legacy of their secondary role: bolt-on casters for the moving of hardware on the lunar surface. A capture system on each MULE rover allowed it to attach to a trunnion on the leg of the LSAM or one of the footpads of the Minerva core module and lift it off the ground, leaving the smaller rear wheels in the air and the weight of the leg balanced on the two large forward wheels. With all four MULEs attached, the LSAM or Minerva core was essentially putting on roller skates, and could be transported at as many as two kilometers per hour.
After landing, the crew’s first EVA was spent deploying and guiding the four mules to attach to the legs of their Minerva 3B LSAM. Thus, their LSAM was converted into a massive pressurized rover. That afternoon and evening, the crew used the mules to tow their LSAM along the first few hundred meters of the traverse to the landing site of the Minerva 3A cargo LSAM. The
Conestoga lander’s program name was once again apt, a massive vehicle bound for a frontier pulled by mules. This legacy yielded the crew’s name for their Minerva 3B LSAM: the
Prairie Schooner. The next day, the
Schooner completed the traverse to Minerva 3A’s LSAM landing site, and the crew set to work in an afternoon EVA configuring the outpost. The first task was using a remote-controlled mule to drive the TOPAZ-II reactor to its final emplaced potion at the end of a 300 meter long power cable. Next, the crew used the Minerva 3A LSAM’s onboard crane to lower the core module to the surface, then used the mules to position both the core module and the
Prairie Schooner into their proper placement relative to the LSAM 3B lander. The third day on the surface was spent attaching the four pressurized tunnels and coupling the base’s three modules together. Overnight, the ground crew carried out tasks to fill the four Habitanks with breathable atmosphere mixtures. Day four on the surface marked the first day without an EVA, as the crew worked all day inside to open up hatches from the airlock into
Schooner's two Habitanks, gain access to the Core Module from there, then repeat the process to open up the LSAM 3A Habitanks. With all five major modules linked into the same pressurized volume, life support systems, and power grid, the crew was able to spend the final days of lunar dusk on a series of short-range EVAs, conducting local site science and emplacing several small experiment packages in the long lunar dusk.
Over the course of the two-week lunar night, Minerva 3’s crew settled into their new base. They finished outfitting the four Habitanks into a short-duration outpost. The two Habitanks aboard
Schooner were fitted out as bunkrooms, ensuring that should a problem arise during the night all four expedition crew would already be aboard the LSAM carrying an ascent stage. The two Habitanks aboard the Minerva 3B cargo lander became a geology lab and an EVA preparation area, while the core module contained the small galley, wardroom, and outpost control center. With the modules outfitted, the crew moved from engineering into focusing on science. In cooperation with selenologists in backrooms on the ground, the commander and science mission specialists reviewed the samples gathered on their initial traverses and made detailed plans for the exploration to follow once the sun rose again. In addition to the outfitting tasks and geology review, the long lunar night offered the chance for long-duration exploration of the human body in lunar gravity. The downtime meant precisely calculated exercise routines on the outpost’s folding treadmill and weight bench went uninterrupted by the strenuous activities of near-daily EVAs.
By the time the sun rose in March of 2001 and the Minerva 3 crew could go about the final two weeks of their month on the lunar surface, the legacy of
Enterprise had been well and truly extended to the moon. The Minerva crew made use of in-space conversion experience developed on
Enterprise and
Enterprise-heritage EVA suits, exercise equipment, and biomedical expertise. When the Minerva 3’s crew departed the lunar farside, they left behind a powerful outpost for any future explorers to further develop. Within the ten-year lifespan of the cabin’s TOPAZ-II reactor, the base could be easily repressurized and reactivated for expansion. Thus, the four Class-B outpost missions would each lay the groundwork for a full lunar base at multiple sites around the moon. For those who doubted such a capability, a fresh explosion of applications for platforms in Earth orbit provided a model to examine closely.
Artwork by:
@norangepeel (
Cass Gibson on Twitter),
@nixonshead (
AEB Digital on Twitter), &
DylanSemrau[/I]