During my recent appearance on The Space Show, a caller questioned the need for people on the Moon. If teleoperated robots can be used to mine resources, manufacture useful products, and set up a lunar outpost, as I have proposed, why do we even need people on the Moon? The caller’s question touches once again on the age-old argument about the transport and support of humans in outer-space, where their presence is both mass- and power-intensive and thus, more costly. But we shortchange humanity if we fall into the trap of believing that a human presence on the Moon (or in space in general) is either not necessary or that it is only required for making repairs, or for updating equipment.
Now that returning to the Moon is in the news, “Why send humans into space at all?” will be asked, again, as it lies at the heart of a very old debate and battle about space. It is the same question that spawned the 2014 Congressionally mandated study by the National Academy of Sciences. That effort posed two “enduring questions”: How far can humans go and what can they accomplish when they get there? But how can anyone truly know the answers to those questions or make sweeping pronouncements about them? Fortunately, because we’ve had 50 years of human space missions, we have demonstrable evidence about the “usefulness” and promise of humans living and working in space.
In December, we’ll celebrate the 45th anniversary of the Apollo 17 mission of 1972 – the first (and so far, only) mission to fly a professional geologist to the Moon – Lunar Module Pilot Jack Schmitt. The Apollo 17 landing site was a complex, multiple objectives site whose complete and thorough understanding and characterization was not likely within the allotted 3-days there. Nonetheless, Apollo 17 crewmembers Commander Gene Cernan and Jack Schmitt traversed and explored the Taurus-Littrow valley “from one end to the other” (as Gene would say from the Moon), and where they made several significant discoveries. They found highland rocks of extreme antiquity, almost as old as the Moon itself (4.6 billion years). They sampled large boulders that represented the remnants of ancient collisions that created the large, circular mare basins more than 3.9 billion years ago. They discovered orange and black soil at Shorty crater, which later was found to be composed of tiny beads of glass created when lava generated 100s of km deep within the lunar interior erupted and sprayed into space and fell back to the surface. And they collected pieces of material thrown out from one of the youngest large craters on the Moon, Tycho, more than 2200 km distant and whose impact occurred “only” 100 million years ago. Eight hundred and forty pounds of lunar rock and soil samples were returned to Earth by American astronauts over six lunar missions. These samples have given a tangible, invaluable context to scientists studying the Moon remotely, for over 48 years.
Could autonomous machines or those under remote control have carried out this complete and thorough exploration of a complex geologic landing site? Most scientists involved in the Apollo program would argue that machines could not have accomplished what the Apollo 17 crew managed to do. Certainly, scientists studying Mars via rovers have often wished that a thinking, walking and talking human could replace that machine. Productive geological fieldwork requires more than the ability to make measurements and pick up rocks – it is important to sample the right rocks, but also to put visual and mental data into a conceptual framework that guides the geologist toward reconstructing the history and processes of a planet. Of course, “grab samples” can be informative when the site is geologically simple and the rocks have a clear context. An example of this might be collecting samples from the youngest lava flow on the Moon. A scoop of fresh regolith from such a site would most certainly contain chips of lava from that flow, allowing for the determination of its composition, age and the nature of its source region. But complex areas, where comprehensive studies demand a real time, in-depth, working knowledge of complicated geologic “mixes,” require humans who can recognize and mentally process what they see before them.
Fieldwork is a complex discipline, whereby an experienced geologist maps an area and chooses samples – not just rocks picked up at random, but rather carefully chosen – significant and representative samples that inform us about process and history. In any natural setting, literally billions of bits of data could be collected. And that’s what a machine does – it collects data. A human field scientist also collects data, but they also are able to high-grade it by collecting only the most significant and relevant data. It takes extensive study, then training and experience in the field, to be able to recognize the significant and distinguish it from the trivial – to see the big picture. We often remark on the Mars Exploration Rovers for their accomplishments, yet for all the data collected, we still cannot draw a simple geologic cross-section of those landing sites, and we still do not know the origin of many of the rocks at the site (igneous or sedimentary). A human geologist would have obtained this important information after a few hours of fieldwork. The mass- and power-intensive humans give a big return on their investment.
In addition to fieldwork, humans possess other qualities that machines do not. The ability of people to recognize, diagnose and solve equipment malfunctions has been proven time and again throughout the history of the space program. The Apollo 17 crew not only explored the valley of Taurus-Littrow, they also deployed an experiment package that required careful installation and alignment. They fabricated and replaced the fender of their lunar rover by using the famous stand-by of all terrestrial repairmen, duct tape and plastic maps (if the rover fender had not been replaced, the dust kicked up by the rover wheels would have soon coated all electronic equipment, leading to overheating and termination of the surface exploration). During the Skylab program (1973), repair work by the crew saved the crippled space station after it was damaged during launch. Literally heroic efforts by Pete Conrad and his crewmates Paul Weitz and Joe Kerwin allowed not only habitation of the overheated Skylab, which was then used by two subsequent crews, but literally saved the entire program. When it was discovered after launch that the mirror of the Hubble Telescope had been ground incorrectly, the crew of Shuttle Mission STS-61 were sent on a mission to put corrective lens on the telescope, again saving the entire program. The assembly and numerous repairs and maintenance of the International Space Station (ISS) require the use of both human and robotic assets to complete, without which the program certainly would not have survived. And this new era in space spawned an explosion of engineers and scientists, and dominated our culture with space movies, architecture, fashion and technology.
Fortunately for humanity, people are required in space to do what only people can do (while also dreaming up new things to do and new ways to do them) – tasks requiring experience and knowledge guided by reasoned judgment and imagination. The ability to act and then learn from such action is critical. People will always innovate solutions for seemingly intractable problems that may arise. A combination of fine-scale manual dexterity and expert, informed knowledge and the ability to react, creates an ease of capabilities in space unachievable by machines alone. The template created during the assembly of the ISS – in which people using robotic machines assembled a complex spacecraft in orbit – is the most likely and productive path for future space activity of all kinds.
Do we need people on the Moon? Fortunately, the answer is a resounding “Yes!” Humans bring unique capabilities that are needed to accomplish new things – unknowable things, things that will enhance our lives on Earth. Studies that conclude that only robots should conduct space and surface operations – as people require protective equipment and habitats – is shortsighted and harmful to a vibrant, intelligent, and inquisitive society. Both humans, and the machines they create to assist them, are required for success in this grand adventure.