by Buzz Aldrin
All this is preface to a major judgment—one that I feel NASA planners are dodging. There is no reason to make a humans-to-Mars program look like an Apollo moon project.
We need to start thinking about building permanence on the red planet, and what it takes to do that. I feel very strongly about this. This is an entirely different mission than just putting people on the surface of that planet, claiming success, having them set up some experiments and plant a flag, to be followed by quickly bringing the crew back to Earth, as was done in the Apollo program.
Curiosity rover, now on Mars, is a robotic geologist.
(Illustration Credit 7.1)
What are you going to do with astronauts who first reach the surface of Mars and then turn around and rocket back homeward? What are they going to do, write their memoirs? Would they go again? Having them repeat the voyage, in my view, is dim-witted. Why don’t they stay there on Mars?
No question, this is a very big, high-level decision that needs to be made. I can guarantee you, if we have anything like the legislative branch of government in the future that we have today, the first tragedy at Mars with a crew would mean cancellation of the program. And that’s all we do about Mars for another century.
I suggest that going to Mars means permanence on the planet—a mission by which we are building up a confidence level to become a two-planet species. At Mars, we’ve been given a wonderful set of moons—two different choices—from which we can pre-position hardware and establish radiation shielding on the Martian surface to begin sustaining increasing numbers of people—not just one select group of individuals. To succeed at Mars, you cannot stop with a one-shot foray to the surface.
It will be a historical moment long remembered when the U.S. President commits the nation to permanent human presence on Mars. Let me hypothesize a political scenario on the 50th anniversary of Apollo 11’s landing on the moon, in 2019. The U.S. President, whoever that may be, takes the opportunity to direct the future of human space exploration, pioneered by Americans, by stating in a speech: “I believe that this nation should commit itself, within two decades, to establish permanence on the planet Mars.”
That statement will live throughout history, committed to memory on Earth and by the first Mars settlers. In response, around 2020, every selected astronaut should consign to living out his or her life on the surface of Mars.
So why send humans to Mars in the first place?
There is common agreement that humans trump machines in many ways. They offer speed and efficiency to perform tasks. On-the-spot astronauts offer nimbleness and dexterity to go places that are challenging for robots to access. Then there are the innate smarts, ingenuity, and adaptability of a human to evaluate in real time a situation, then improvise to prevail over surprises.
Still, there is a softer side of placing humans on Mars. There are behavior, performance, and human factor unknowns. Living far from Earth in a remote and confined environment will surely induce physiological and psychological stresses. One oddity that is sure to haunt the first humans on Mars—loss of privacy.
You already get a sense of that when you tune in to televised linkups with International Space Station crews. Lots of cameras are positioned everywhere. Of course, the communications time lag between Earth and Mars is a factor. There’s a way to start simulating today how best to handle Earth-Mars communications time delays. The International Space Station could simulate and teach people on both ends how to deal with the person-to-person communications delay. What this might boil down to is that every interplanetary traveler has to be a procrastinator!
Other than our limited trips to the moon via Apollo, humans have never embarked upon a mission that’s on a par with marching off to Mars; the best analogs so far are Antarctic, undersea, and International Space Station expeditions, but these are distant cousins to the isolation, remoteness, and challenges that will be faced by courageous men and women stationed on Mars, many millions of miles from Earth.
Vehicles and habitations envisioned by NASA for a Mars post
(Illustration Credit 7.2)
A NASA Mars reference document emphasizes the need for more study of the composition of a Mars crew, based on personal and interpersonal characteristics “that promote smooth-functioning and productive groups, as well as on the skill mix that is needed to sustain complex operations.”
Establishing a footing on distant Mars is a complex operation. The challenge ahead is monumental and historic. We are on a pathway to homestead the red planet courtesy of robotic explorers that are surveying what now looks like unreal real estate. Nonetheless, there’s familiarity with remote Mars. It did not go unnoticed that the first color images transmitted from the Curiosity rover showed layered buttes and other features reminiscent of the southwestern United States.
There is an evolving comfort level with Mars. It is a perspective that beckons us to push forward.
“Retuning” Mars Exploration
I recently took part in a major gathering of Mars aficionados, the Workshop on Concepts and Approaches for Mars Exploration, held June 12–14, 2012, at the Lunar and Planetary Institute in Houston, Texas. It was a heady affair, tackling major issues, including how best to respond to President Obama’s challenge of sending humans to orbit Mars in the 2030s.
Some 185 participants came together to share ideas, concepts, and capabilities and address critical challenge areas, focusing on a near-term time frame spanning 2018 through 2024, and a mid- to longer-term time frame spanning 2024 to the mid-2030s.
It was made clear up front that in today’s financial times, investment in Mars exploration is tough. The workshop had as a major goal the identification of new concepts and “retuning” ideas for Mars exploration in light of current harsh fiscal realities.
Looking forward into the next decades, all agreed that international collaboration held the greatest potential to enhance future Mars programs—operating in a one-for-all, all-for-one mode. In this light, for instance, any ambitious, complex, and costly Mars sample-return campaign—robotically grabbing and rocketing back to Earth specimens of the red planet—was eyed as dependent upon a long-term and enabling collaboration with other nations.
As always, front and center is the power of Mars to entice us to brood over some key, compelling questions, particularly if life ever was sparked into being there. If so, did it perish or is it still resident on the planet? But also understanding the Martian climate and atmosphere, including the evolution of Mars’s surface and interior, can be looped back into grasping the past, present, and future of Earth. The geologic record of early Mars has been preserved, chronicling the period more than 3.5 billion years ago when life is likely to have started on Earth—a time period whose record is mostly missing on our own planet. Can Mars exploration allow us to turn back the clock and see if life arose elsewhere in our solar system neighborhood?
That’s all good science, but we have more urgent reasons to study the environment of Mars: It is mandatory for assuring the safe landing and operation of future robotic and, more important, human missions to the planet. Obviously, unraveling the inner and outer workings of Mars will be a labor-intensive human activity.
There were several challenge areas addressed by workshop attendees, among them what kind of human health-risk reduction is required to support crewed missions around Mars, at Phobos or Deimos, or on the surface of the planet. There’s a need to take into account ionizing radiation and the toxicity of soils, among other items.
Analyses of interplanetary trajectories from the vicinity of Earth to the Mars system and return were identified, distinguishing those that offer efficiencies in transportation systems, including transit time, cost, et cetera. This includes looking at a variety of Mars orbits and possible rendezvous with or landing on Phobos or Deimos, and scrutinizing trajectories of Earth-moon L2 to the Mars system, and return.
Mars surface system capability is another challenge, whether lighter rover systems able to speed across the planet
or equipment that demonstrates in situ resource utilization (ISRU). ISRU demos can shake out equipment to support human surface exploration and settlement—projects for extraction and long-term storage of oxygen and/or hydrogen from available Martian resources in the atmosphere, hydrated minerals on the surface, and digging into Mars to utilize subsurface ice.
An artist’s sense of a “space hab” on Mars includes a greenhouse farming unit.
(Illustration Credit 7.3)
Here’s an imperative. Incorporating ISRU into human exploration of Mars and its moons necessitates a shift in mind-set—not taking everything you need by launching it from Earth. You don’t have to haul everything with you because there are available resources at destination’s end. There are new ISRU products that can be tapped, such as methane, magnesium, perchlorates, and sulfur. ISRU systems are vital to extract “made on Mars” products from the Martian environment, such as water, oxygen, silicon, and metals for life support, rocket fuels, and even construction materials. Putting in place an effective ISRU system will lessen the need for resupply missions and fully support an off-Earth outpost.
One major realization from the workshop: There is synergy in enabling technologies between robotic and human missions and this increases as future robotic missions become more ambitious. This synergy can manifest itself in a couple of ways, as identified in the meeting:
• Technologies, such as entry, descent, and landing systems, when scaled for application to human missions, enable greater payload mass for robotic missions.
• Leveraging technologies needed for human missions, such as for ISRU and liquid oxygen-methane propulsion systems, can benefit a Mars sample-return mission, due to the potential for reduction in launch and entry mass, hence reducing mission cost.
Of key interest to me, several breakout paper observations produced at the workshop focused on the long-haul vision of preparing for human exploration.
Continual scientific study of Mars is an important prelude to enable targeted, cost-effective human exploration. There’s need to extensively characterize the surface and subsurface of Mars. Also, the polar regions of Mars are not only scientifically compelling, they merit study as resource-rich human destinations.
Phobos and Deimos were viewed by workshop participants as “important destinations that may provide much of the value of human surface exploration at reduced cost and risk.” It was reported that, as natural space stations and a potential “base camp,” these two moons can support teleoperation of payloads on Mars along with habitat buildup, while alleviating some planetary protection issues.
Thanks to robotic surrogates, surprises from Mars will keep coming. NASA’s Mars program provided the first close-up photo of the red planet in 1965. Our view of that world has been transformed by camera-snapping orbiters from high above, as well as by the groundbreaking Phoenix lander, a run of rovers—Sojourner, Spirit, and Opportunity—and now the far more capable Curiosity. They serve as vital precursors for human exploration of Mars—but there is far more work to do.
Flesh and Bone Versus Nuts and Bolts
In striving for settlement of Mars, new technologies must be mastered. Agriculture under extreme conditions, power generation, radiation protection, and advanced life-support systems are called for. Autonomous and highly robust equipment is necessary. To counter the typical 40-minute, round-trip speed-of-light communications time between humans on the surface of Mars and ground controllers on Earth, control must be in the hands of those on the red planet.
Arguably, one of the better looks at what an early Mars encampment might constitute can be derived from Human Exploration of Mars Design Reference Architecture 5.0, issued in 2009 by NASA’s Mars Architecture Steering Group. The document was edited by Bret Drake of NASA’s Johnson Space Center in Houston, Texas.
NASA’s Mars design reference architecture details the systems and operations for a trio of human trips to explore the surface of Mars, carried out over roughly a decade. These first three missions, as the document explains, were designated because the development time and cost to achieve the basic capability to carry out a single human Mars mission “are of a magnitude that a single mission, or even a pair of missions, is difficult to justify.”
Astronauts will use various rovers to expand our knowledge of Mars.
(Illustration Credit 7.4)
These first three human Mars missions are also assumed to have been preceded by a series of test and demonstration missions on Earth, in the International Space Station, in Earth orbit, on the moon, and by robotic Mars missions “to achieve a level of confidence in the architecture such that the risk to the human crews is considered acceptable,” the report says.
While I differ with sections of this report, it does offer a look at the “need-to-haves” in terms of a starter kit for living on the red planet.
For example, once a crew lands they will need effective and reliable shelter to permit outside excursions. The crew can investigate the Martian surface in a wheeled exploration vehicle, say for weeks at a time, without returning to the habitat. Strolling Mars-walkers will need protection from radiation and dust to safely survey and work on the surface.
From an operational perspective, the first humans to set foot in a Mars landing zone and habitat locale would find themselves at a broad, relatively flat, centrally located area for safety’s sake. That means, however, crew and cargo may be far removed from features of scientific significance, beyond a practical walking range for a crew. Pressurized rovers could tote equipment, such as drilling gear to penetrate the Martian surface to moderate depths. The ability to move a drill from location to location would also be desirable. Samples would be returned to the primary habitat that’s equipped with a laboratory for extensive analysis.
Not all crew members would trek across the Martian landscape. There would always be some portion of the crew in residence at the habitat.
The NASA report observes that “a strong motivating factor for the exploration of Mars is the search for extraterrestrial life.” However, the document goes on to explain that this search could be permanently compromised if explorers carry Earth life and inadvertently contaminate the Martian environment. Additionally, there is need to guard against the remote possibilities that samples transferred from Mars could support living organisms that might reproduce on Earth and damage some aspect of our biosphere. Avoiding both of these eventualities is termed “planetary protection.”
One other point—and it’s a bit of a catch-22. The fact is that human beings harbor large microbial populations in and on their bodies, and these microbes are constantly reproducing. Even with advances in space suits and habitat construction, it appears impossible that all human-associated activity on Mars would not foul the Martian environment. That prompts the rationale that human missions should be sent only to sites where this is tolerable. But that also means avoiding astrobiologically interesting sites on Mars. Once again, use of sterilized equipment, operated either from a distant, crewed Mars outpost or by astronauts posted at a Mars moon, is likely to be necessary.
Mars researchers Chris McKay and Carol Stoker at NASA’s Ames Research Center, along with Robert Haberle and Dale Andersen of the SETI Institute, have long pondered a science strategy for human exploration of Mars. In their view the region containing the Coprates Quadrangle and adjacent areas should be the site of the first human base on Mars. This region is festooned with volcanoes, ancient cratered terrain, and numerous outflow channels; it includes the NASA Viking 1 landing site. That spacecraft settled in on Mars on July 20, 1976, and was the first attempt by the United States at a robotic landing on the red planet.
Exploring Mars: a blend of humans and robots
(Illustration Credit 7.5)
The main base will occupy the Coprates Quadrangle region, these scientists suggest, and other reachable spots can be maintained as remote field outposts. Orchestrated as an “emplacement phase,” crews would survey the landing site area to determine the state and distri
bution of volatiles, especially water. Martian atmospheric gases could be sucked into machinery to supply breathable air for crews, even for cranking out propellants for launching vehicles from the surface of Mars. Resource extraction units would be primed to start stockpiling useful resources. Such stockpiles can provide safety backup to reserves a crew would bring from Earth, supplementing what’s available for future arrivals that make their way to Mars.
Crew members set up test equipment for polar exploration on Mars.
(Illustration Credit 7.6)
Deposit, No Return
Long-range thinking has begun on a Mars Homestead Project, one that is identifying the core technologies needed for an economical, growing Mars Base built primarily with local materials.
Bruce Mackenzie, co-founder and executive director of the Mars Foundation of Reading, Massachusetts, along with an active team of like-minded individuals, has plotted out how to build and operate the first permanent settlement on Mars. Some locally derived materials on Mars have been singled out for initial settlement construction, like fiberglass, metals, and masonry, either for unpressurized shelter or covered with Martian regolith to hold the pressurized volume. Polyethylene and other polymers can be made from ethylene extracted from Mars’s carbon dioxide–rich atmosphere.
The ultimate goal of the project is to build a growing, permanent settlement beyond Earth, thus allowing civilization to spread beyond the limits of our small planet.
Mackenzie explains there are subtle differences in the technologies required for human settlements on Mars, compared to preliminary human exploration of the red planet. Obviously, duration and reliability of life-support systems is one such difference. So, too, is the need for long-range surface mobility to gain access to a variety of locations on the planet. Lastly, building off experiences gained from the International Space Station, astronauts exploring Mars will need to fabricate hydroponic growth labs where vegetables can be grown. These crops will provide Mars settlers with added nutrition and variety.
