Why is human Mars exploration so surprisingly hard?
by James Oberg
Monday, August 17, 2009
As space policy experts mull over alternative strategies for astronaut exploration of the solar system, possibly including human flight to Mars, the recently-concluded fortieth anniversary celebrations of the Apollo 11 moon landing inspire one specific question: what’s taken so long?
In the heady days of the Apollo triumphs, even the “pessimistic” forecasts imagined it might take as long as twenty years to get astronauts to Mars. Optimistic schedules put the first footsteps on the Red Planet—another “giant leap for mankind”—as early as 1982.
When it didn’t happen in fifteen or twenty years, or even in twice that period, or even by current plans by twice again that period, the question naturally arose: why not? Had the national will failed? Had our adventurous culture lost its nerve?
| In the heady days of the Apollo triumphs, even the “pessimistic” forecasts imagined it might take as long as twenty years to get astronauts to Mars. |
In recent years a better perspective has become possible, and it is far less disrespectful to the successors of Apollo. Furthermore, it suggests that even with an immediate post-Apollo national decision (and a reasonable budget) to send astronauts to Mars, it would not have proven possible by 1982, or 1989, or even perhaps anytime in the century if the task proved too politically damaging in the face of setbacks.
Here’s the way I’ve come to see it. It should have been no surprise that “On-To-Mars” never happened. The reasons directly affect today’s chances of tackling the task in the near future.
First, since Apollo had gloriously succeeded in its major purpose—restoring American status as the leading high-tech nation in the world—the political support for further spending evaporated in the face of new, more urgent challenges. Apollo had “worked”. Making the point again on a different stage would have added little if any value.
Apollo had worked so well, some argue, that its validation of American aerospace competence was the central factor in giving credibility to Reagan’s Strategic Defense Initiative in the 1980s. Moscow was unable to dismiss it as empty bluster of the sort Khrushchev used to throw around about Soviet missiles, and thus risk losing the threat-effect of their nuclear attack systems. Experts who pooh-poohed the project’s feasibility, in the USSR and overseas, had a major credibility problem since many of them were, or were associated with, experts who also had decreed that Apollo wasn’t going to work either.
Second, the earth-to-orbit transportation infrastructure had been deliberately overbuilt, but this was designed from the start to be a short-term surge. With the post-success downturn of Apollo, critical capabilities such as heavy lift were no longer required: there weren’t any near-term payloads justifying the infrastructure maintenance. The Saturn 5 production facilities were already shutting down by the time the first landing succeeded (extra vehicles had been ordered in case attaining a successful landing took a lot more test flights).
Third, major components of the Apollo team—the experienced engineers, technicians, and managers—had by 1969 chosen to return to “normal” life. Gathered from a hundred separate industries with engineering experience in a thousand projects, these men and women had consciously and intentionally chosen to put their personal lives on hold and devote 60-plus-hour workweeks to the “project of the century”—for a limited period of time. And that period was over. Talented and dedicated people remained, but the breadth of experience that had made the Moon program feasible shrank markedly.
Fourth, in terms of the science harvest of the lunar missions, Apollo had reaped enough raw data to require decades of study to digest it, formulate new theories, and define the new questions that needed answers through on-site exploration. The “cover story” that curiosity had been the driver for Apollo (and would be for its successors) lost validity when the next set of scientific questions would take an academic generation or two to crystallize.
| The engineering challenges of much, much longer space flights far from Earth (with no chance of resupply or rescue) had been grossly underestimated. |
Fifth, there were things we discovered about the hazards of spaceflight that demanded new assessments and the development of new capabilities. For example, extending Apollo-class lunar operations wasn’t merely a matter of carrying more batteries and more sandwiches. The hardware had proven just barely capable of the minimum mission during limited thermal environments and on limited geographical subsets of the Moon. Extending the range in time and space demanded an entirely new generation of space vehicles. For example, the unexpectedly abrasive lunar dust just ate up the Apollo spacesuits, corroding their air seals and jamming their mechanical joints. On the last missions, the suits showed signs of breakdown after only three days of use.
Sixth, the engineering challenges of much, much longer space flights far from Earth (with no chance of resupply or rescue) had been grossly underestimated. Even today aboard the International Space Station less than 500 kilometers from home, proving out truly long-term reliable regenerative life support hardware is only now showing signs of success.
This Apollo-era shortcoming has become clear only in recent years. More rigorous techniques of quantitative risk assessment’ developed in response to Apollo’s preliminary analytical procedures, showed in hindsight that Apollo had indeed been “safe enough” to fly: calculations indicated that crew survival chances were better than 98% and mission success chances were in the 75% range for the early missions. But when applied to the then-popular Mars astronaut mission profiles, the same techniques generated horrifying results: mission success chances were less than 10%, and crew survival chances were less than 50%.
Clearly, a long period of getting a lot smarter would have been needed before serious human interplanetary missions could have been contemplated with 1970s-era technology. Whether that process could have been done without repeated delays, or repeated disasters, is highly questionable.
Which came first? The ability or the desire?
If NASA wasn’t smart enough in the 1970’s to build a human interplanetary vehicle—while being intuitively aware enough to realize that they probably didn’t know how—then how do get that smart now, and recognize when we are that smart? When will human interplanetary flight become even marginally attainable, and how do we get there? Answering these questions may be central to evaluation by national leaders of the strategy options now being formulated by the Augustine team.
| Rather than an originator and innovator, the national space program was then (and may still be now) more an end-user of existing technological capabilities. |
A good get-well step is to stop misunderstanding the nature of the national technology capabilities base available for application to spaceflight. NASA has long been touted as a generator of advanced technologies that later entered the national industrial repertory. Most of these “spinoffs” are anecdotal, even mythical. It looks truer that where NASA has benefited US industrial capabilities it has usually been as an accelerator or concatenator of existing technologies rather than as an originator.
In case after case, and even in patent after patent, NASA’s Apollo team not the originators of radical new breakthrough capabilities. More often they were—and properly so —the harvesters of existing experience and the application to enhanced versions of that know-how to a specific engineering challenge. They learned from the experience of others, most often not merely by reading reports of these technologies but by bringing those experienced people directly into the development teams.
So the opposite of the conventional wisdom may be more accurate—and more useful to realize. Rather than an originator and innovator, the national space program was then (and may still be now) more an end-user of existing technological capabilities. It is a nurturer of promising ideas and prototypes, an exploiter and enhancer of the existing technology base. And under wise leadership it is also a serious dabbler in innovation, identifying missing ingredients in the capabilities spectrum and taking risks to learn new tricks. This is a useful, worthwhile function, but it’s not the common view of “rocket science”.
Realizing this reality helps us understand when the repertoire of national technological, scientific, and medical capabilities approaches a point where focused investigation and acceleration can produce workable hardware for support of a credible strategy to venture beyond low Earth orbit for extended expeditions.
This is where a whole bag of new tricks, from NASA labs and think tanks, and from outside NASA (the so-called “spin-ins”), from US society and from other nations, from military and scientific and commercial projects and others, will come in. Cataloguing the contents of such a bag, and identifying remediable gaps in it, is a task yet to be properly done. But that task must precede any decision-making on what new spaceflight challenges the US is may be realistically capable of attempting.
| Mars will always be hard. It only recently has become sufficiently less hard that we can, at last, just barely realistically dream of getting there. |
And if the technology base is found to be available, even in incomplete form, the final question is how NASA, as an institution, will be able to acquire it, especially under foreseeable budget conditions when the actual non-NASA innovators can’t physically move into NASA offices. NASA’s track record in willingly adopting outside ideas is spotty, to be generous. But the little-appreciated engineering development of genuinely long-lived life support hardware, now bedeviling engineers, operators, and astronauts aboard the International Space Station, is testimony that it can be done, that the unknowns and gaps can be made clear, and that this generation of the space team has what it takes to meet these challenges. It’s been important to relearn this, and for that (and many other reasons), a lot of initial space-station-skeptics (like me) have become grateful to the ISS.
Mars will always be hard. It only recently has become sufficiently less hard that we can, at last, just barely realistically dream of getting there.
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