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Amundsen at the South Pole, one hundred years ago today.

One of the last major milestones in the history of terrestrial exploration was achieved one hundred years ago today – the attainment of the South Pole by Roald Amundsen and his team on December 14, 1911.  His rival, Robert Falcon Scott and crew, were still more than a month away from the pole and (although denying they were in a race) destined for heartbreaking disappointment when they arrived to find the Norwegian flag flapping in the howling Antarctic wind.

The Amundsen-Scott polar drama time stamps a major shift in our thinking about the meaning of exploration.  This shift in our perception of what it means to explore holds ramifications to today’s debates on space policy.  Traditionally, exploration is a very personal activity.  It involves someone’s decision to see what lies over the next hill.  This act is exploration in its purest sense; it dates from the Stone Age and is principally responsible for humanity’s reach into all corners of the Earth.  This exploration is undirected and random –motivated by the human desire to scratch that unrelenting itch of curiosity.  You finance and outfit yourself and go, while adhering to the maxim, “It is easier to ask for forgiveness than to get permission.”

As society grew and evolved, a different type of exploration emerged.  For difficult or expensive journeys to far corners of the globe, people pooled their knowledge and resources to collectively explore the unknown by creating government-sponsored projects.  Until modern times, such exploration was considered to include not only discovery and initial characterization, but also utilization, exploitation and eventually colonization – all with an eye toward wealth-creation.  By the end of the 19^th Century, the regions of the world unclaimed by western powers were all but gone, gobbled up in a frenzy of imperial land-grabs by industrially developed nations.  All that was left were the seas (whose freedom of access for all nations was guaranteed by the British Royal Navy) and the North and South Poles.

The shift of attention to the poles coincided with the rise of science and with it, a significant change in the “exploration” ethic.  It was actually thought at one point in the late 19^th Century that all nature had been finally and thoroughly explained.  After numerous failed attempts to find a Northwest Passage to the Pacific north of Canada (economic motivation), expeditions to the polar regions began to focus on scientific observations and measurements (knowledge gathering).  This shift in emphasis also coincided with a global rise of nationalist conscience, the idea that some nations were destined to discover and conquer remote parts of the Earth.  Given the global extent of the British Empire at that time, the English were particularly susceptible to this idea.

These various motivations were threaded together in the early 20^th Century as science joined with nationalistic chest-thumping to create government-sponsored scientific expeditions to remote locales.  Important and difficult expeditions requiring teamwork and pooled resources became national exploration efforts.  Science became a fig leaf rationale for realpolitik global power projection.  There was still the occasional “because it’s there” type of expedition to some remote mountain or plateau but most often it was privately financed.

And so we come to the Space Age, which in basic terms has followed the knowledge-gathering template of polar exploration.  A new movement for national power projection in space has yet to fully emerge.  National security may be the only motivator of sufficient political power to launch an earnest, national drive into space.  Traditionally the military conducts exploration in peacetime.  In the late 18^th Century, Royal Navy Captain James Cook conducted three expeditions to the Pacific – not for pure science but rather for applied science – to improve navigation for commerce and other purposes.

Perhaps this link to applied science may guide us toward a new understanding of the term “exploration,” or rather, to recover an old meaning that has been lost.  The idea of exploration leading to exploitation (currently tossed aside in the modern equation of exploration and science) could serve as the “new” guiding principle for modern spaceflight.  By making space the singular preserve of science and politics, both are ill served, much to the determent of humanity.  For now, we remain wedded to the template of launch, use, and discard – a modus suitable to an occasional, expensive and limited presence in space but one wholly inappropriate for undertaking the creation of a modern, permanent space faring infrastructure.  Instead, beginning with the creation of a reusable, extensible cislunar space faring system, we should learn how to use space for national interests by using the Moon and its resources.  This will require a long-term research and development project geared to acquiring the understanding and ability to gather and use the resources available to us in space in order to routinely access, explore and exploit cislunar space and the frontier beyond.

This model of a national space program fits the classic understanding of exploration – we go into space as a society and what we do there must have societal value.  Because cislunar space has critical economic and national security value, we need to create a system that can routinely accesses that region of space with robots and people.  Hence, I advocate resource production bases on the Moon, reusable systems, and the build-up of a cislunar spaceflight infrastructure.  Some may not consider this to be “exploration” but the great explorers of history exploited and settled after they found and described.

The attainment of the South Pole one hundred years ago today shifted the meaning of the word exploration and boxed us into an artificial separation of the concepts of discovery and use.  That modern connotation is both arbitrary and historically incorrect.  Exploration includes exploitation and we can exploit the Moon – our nearest planetary neighbor – to create a permanent space faring capability. The development of cislunar space is exploration in the classic sense – a plunge into the unknown:  Can we do this?  How hard is it?  What benefits – beyond those we can recognize now – might we realize from it?   History shows that such undertakings promote new discoveries by opening windows of innovation and generating new streams wealth creation.

Note: My friend Don Pettit has similar thoughts in his blog post today.

Next stop?

Of all the idiocies that make up our current lack of a genuine policy for civil space, the imperative to find some destination that is not the Moon is the most telling sign of an absence of thoughtful leadership.  For an example of the pointlessness to which this reasoning can go, take a look at a recent post at Scientific American, arguing for a human flyby mission to Venus.

That’s right – Venus.  The planet that makes Jupiter’s moon Io look like an island in the Bahamas — a locale of sea-bottom pressures, lead-melting temperatures and sulfuric acid rain.  Specially built robotic devices last for (at best) an hour or two before breaking down into an inert lump of metal.  This place is now being advocated (seriously) as a destination for human spaceflight.  How did we arrive at such a state?

Simple – by a deliberate act of programmatic destruction.  The Moon was to be our first destination on the long road into the Solar System.  But that goal was discarded, allegedly on the grounds that “we’ve been there,” but in reality because it was a destination that could be reached on reasonable timescales for affordable amounts of spending.  Thus, a failure to return to the Moon could not be blamed on factors other than program mismanagement or agency incompetence.  In other words, it was a realistic goal against which progress could be assessed.

What replaced lunar return?  That’s a bit more muddled, but vague notions were advanced that human missions “beyond low Earth orbit” could be undertaken only if NASA was freed from the onerous requirement to build new spacecraft and launch vehicles.  Thus, we would purchase commercial launch services for delivery of people and payload to LEO and use the agency budget to develop “new and exciting technologies” to make more distant goals reachable.

As this proposed pseudo-policy played itself out over the ensuing months, its essential hollowness became ever more apparent.  Despite the quasi-religious beliefs of some space buffs, there is no “magic beans” technology to make spaceflight infinitely cheap and infinitely capable.  There is no commercial human spaceflight industry.  And other than the now-discarded lunar surface, there is no worthwhile human destination reachable within the next 15 years.

Yet many in the space business pretend otherwise.  Hence, we get articles like the “Humans to Venus” piece.  What’s wrong with this concept?  Simply put, there is nothing humans can do on a Venus flyby that a robotic spacecraft could not accomplish, while there are things a robotic spacecraft could do there that humans cannot.  The real need for Venus is to get high-resolution radar images and gravity data of the planet to extend and supplement the reconnaissance mapping of the Venera and Magellan missions of the past century.

To get such high-quality image data, one must put a spacecraft into orbit around Venus.  This is a fairly straightforward task for a robotic mission; you can use the atmosphere of Venus to aerobrake, which will gradually slow the spacecraft down and allow it to slip into orbit.  The problem is not getting into orbit around Venus – it’s getting out of it.  Venus is a large planet (almost as big as the Earth) and it takes significant energy to achieve escape velocity.  With a robotic spacecraft, we don’t worry about that because there is no need to return it to Earth.  I suspect that a human crew might feel differently about such a proposition.

In plain fact, there is nothing of any real scientific value that a human crew can do during a few-minutes-long flyby encounter with Venus.  So we are talking about undertaking a months-long trip through interplanetary space, fully exposed to cosmic radiation and solar particle events, for a momentary view of an extremely hot planet of bright, featureless cloud tops.

Space advocates are desperately looking for something people can do and somewhere they can go in space on timescales of less than multiple decades at costs of less than hundreds of billions of dollars.  If only there where some place we could get to within a decade or so, for a cost that doesn’t bust the latest budget.  If only there was a destination in space where human judgment, knowledge and expertise would play a real time critical role in mission success and where new capability would be realized.

If only…..

The north pole of the Moon: Real or facsimile?

Of all the wonders depicted in science fiction books and movies, one of the most intriguing is the machine that makes anything that you need or desire.  Merely enter a detailed plan, or push the button for items programmed into the machine – dials twirl, the machine hums and out pops what you requested.  Technology gives us Aladdin’s Lamp.  A handy device that will find many uses.

We’re not quite there yet but crude versions of such imagined machines already exist.  These machines are called “rapid prototype” generators or three-dimensional printers.  They take digitized information about the dimensions and shape of an object and use that data to control a fabricator that re-creates the object using a variety of different materials.  Typically, these machines use easy to mold plastics and epoxy resins but in principle, any material could be used to create virtually any object.

What’s the relevance of this technology to spaceflight and to the Moon?  One of the key objects of lunar return is to learn how to use the material and energy resources of the Moon to create new capabilities.  To date, we have focused our attention on simple raw materials like bulk regolith (soil) and the water found at the poles.  It makes sense to initially limit our resource utilization ambitions to simple materials that are both useful and relatively massive, which currently have those killer transportation costs when delivered from Earth.  Bulk regolith has many different uses, such as shielding (e.g., rocket exhaust blast berms) as well as raw material for simple surface structures.

However, once we are on the Moon and have met the basic necessities of life, we can begin to experiment with making and using more complex products.  In effect, the inhabitants of the Moon will begin to create more complicated parts and items from what they find around them, just outside their door.  The techniques of three-dimensional printing will allow us to discover what makes life off-planet easier and more productive.  We will experiment by using the local materials to maintain and repair equipment, build new structures, and finally begin off-planet manufacturing.

During the early stages of lunar habitation, material and equipment will be brought from Earth.  With continued use, particularly in the harsh lunar surface environment, breakdowns will occur.  Although initially we will use spare parts from Earth, for simple uncomplicated structures that are needed quickly, a three-dimensional printer can make substitute parts using local resource materials found near the outpost.  Most existing 3-D printers on Earth use plastics and related materials (which are complex carbon-based compounds, mostly derived from petroleum) but some processing has used concrete, which can be made on the Moon from sieved regolith and water.  In addition, we also know that regolith can be fused into ceramic using microwaves, so rapid prototyping activities on the Moon may eventually find that partially melting particulate matter into glass is another way to create useful objects.

The lunar surface is a good source of material and energy useful in creating a wide variety of objects.  I mentioned simple ceramics and aggregates, but additionally, a variety of metals (including iron, aluminum and titanium) are available on the Moon.  Silicon for making electronic components and solar cells is abundant on the Moon.  Designs for robotic rovers that literally fuse the in-place upper surface of the lunar regolith into electricity-producing solar cells have already been imagined and prototyped.  We can outsource solar energy jobs to the Moon!

These technical developments lead to mind-boggling possibilities.  Back in the 1940s, the mathematician John von Neumann imagined what he called “self-replicating automata,” small machines that could process information to reproduce themselves at exponential rates.  Interestingly, von Neumann himself thought of the idea of using such automata in space, where both energy and materials are (quite literally) unlimited.  A machine that contains the information and the ability to reproduce itself may ultimately be the tool humanity needs to “conquer” space.  Hordes of reproducing robots could prepare a planet for colonization as well as providing safe havens and habitats.

We can experiment on the Moon with self-replicating machines because it contains the necessary material and energy resources.  Of course, in the near-term, we will simply use this new technology to create spare parts and perhaps simple objects that we find serve our immediate and utilitarian needs.  But things like this have a habit of evolving far beyond their initial envisioned use, and often in directions that we do not expect; we are not smart enough to imagine what we don’t know.  The technology of three-dimensional printing will make the habitation of the Moon – our nearest neighbor in space – easier and more productive.  Even now, creative former NASA workers have found a way to make this technology pay off.  In the future, perhaps their talents could be applied to making the Moon a second home to humanity.

Note:  The image at the beginning of this post is a model of the lunar north pole, made using a three-dimensional printer and LRO laser altimetry data by Howard Fink of New York University.  The scale of the model is about 30 cm across.

The lunar feature Ina, an extremely young, unusual depression that may represent a gas eruption site on the Moon. LROC narrow angle camera images.

There are times when seemingly unrelated discoveries about other planets come forward to enlighten us about the history and processes of the Moon. A recent paper, using data from the orbiting MESSENGER mission mapping Mercury, describes a number of newly discovered rimless pits and depressions.  These pits (called hollows by the mission team) are difficult to explain by impact processes and are hypothesized to be the products of outgassing from the planet’s interior.  They are often associated with color anomalies (which implies compositional differences from the surrounding terrain) and frequently found on the floors of impact craters and basins.

Impact craters come in a wide variety of sizes, but within selected size ranges, they all appear more or less similar.  Small craters are nearly perfectly round and bowl-shaped with smooth rims that are raised above the surrounding terrain.  Craters with irregular shapes and no raised rims suggest that processes other than impact might be at work.  It has been suggested that on Mercury, these “hollows” were created by the violent release of volatile substances.  Such a release of gas under pressure accompanies volcanic eruptions called pyroclastic, meaning “fire-broken” (fine liquid rock (magma) fragments spewed into space and cooled during flight).

We’ve known about pyroclastic eruptions on the Moon for many years, evidenced by the green glass of the Apollo 15 site and the orange-black glass from Apollo 17.  Careful search of the images taken from lunar orbit reveal the rimless pits that served as vents for the pyroclastic eruptions that produced these Apollo glasses.  They are distinct from impact craters and often are found on the floors of craters and basins along fractures, the conduit by which volcanic magma travels to the lunar surface.

Sometimes pit craters or “hollows,” found across the surface of the Moon, take unusual form.  The kidney-shaped feature shown above is named Ina; after its discovery in one of the Apollo orbital images, it was informally named the “D-caldera” after its shape and the interpretation that it represented a volcanic collapse feature.  Ina is about 3 km across and consists of a series of small platforms, mounds and holes within a larger irregular depression.  Other similar pits and hollows occur elsewhere on the Moon (e.g., on the floor of Rima Hyginis).  And while not major features, they have been found often enough to bother many lunar scientists, who had no good explanation for their origin.

About five years ago, we got a clue as to the possible origins of these features.  Pete Schultz and associates from Brown University published a paper showing Ina displayed unusual spectral reflectance characteristics.  The slow micrometeorite bombardment of the Moon adds craters to the surface and also makes small iron-rich glass particles that darken and redden the surface.  As these glass particles build up in the soil, a soil is said to “mature.”  Fresh surfaces are more “blue” in color (actually, less red) and become redder with time as the soil matures.  Most lunar features show age or “become mature” on timescales of millions of years.  Ina shows very few impact craters on top of it, meaning that geologically, it is very young.  Moreover, the soils associated with Ina are much bluer than surrounding areas.  Both of these observations suggest that Ina is young with immature surfaces.

How are these features created?  Significant volcanism on the Moon largely stopped at least a couple of billion years ago.  The Brown team thought that the combination of young age, low maturity and unusual morphology suggested a relatively uncommon pit-forming process.  They proposed that the explosive release of volatile substances from the lunar interior would have disrupted the surface, created a chaotic mixture of rock and soil, exposed fresh surfaces (creating the immature spectral signature), and formed a collapse depression caused by the instantaneous removal of mass from below.

Now we can see that the new Mercurian hollows have morphologies displaying spectral anomalies similar to the lunar collapse pits such as Ina.  The new data suggest that Mercury contains significant volatile substances.  These volatiles must be present at some depth, accumulated under high pressure until crustal failure ensues and a massive gas release results in an “eruption.”  This explosive event leaves behind a chaotic, disrupted surface (“immature,” with fresh bedrock and deep regolith “newly” exposed to space).

In the case of Ina on the Moon, its extreme youth is suggested both by the lack of overlying impact craters of almost any size, as well as the sharp preservation of topography in its cliff and pit interior morphology.  This extreme youth may be on the order of thousands to hundreds of thousands of years, not the millions and billions of years that typify most lunar landforms.  Such youth and the widespread distribution of Ina-like collapse pits across the lunar surface implies that outgassing events are occurring on the Moon now; it is highly unlikely that we were just lucky enough to find a singular or unique occurrence.

What might these volatile substances be?  Before the recent lunar missions flew, it was common to declare that water was not a possibility.  However, we recently discovered from study of the lunar samples that water was present in the deep interior of the Moon during the epoch of mare volcanism three billion years ago; water could still be present in the subsurface.  There are many other volatile substances that could be responsible as well, including carbon monoxide, hydrogen sulfide, gaseous sulfur, as well as other more exotic gases.  Because the compositions on Mercury are poorly known, the possibilities for exotic materials there are even more extensive.

The explosive release of gas from the deep interior (without the eruption of magma) appears to be an ongoing lunar process.  This gas release could provide at least a partial answer to two vexing lunar problems: the accumulation of volatiles at the poles of the Moon (discussed in my blogging many times, most recently HERE) and the infamous phenomena of Lunar Transient Phenomena (LTP), described as glowing reddish “clouds” hovering over the lunar surface that mysteriously appear and disappear.  Telescopic observers have reported seeing LTP for many years.  Unfortunately, we have not been able to verify and document these events, largely because they are transient.  Now we have direct morphological evidence for the venting of gas from both planets, making it possible that at least some LTP might be related to gas release from inside the Moon.  Stay tuned – the book of the Moon continues to be rewritten and expanded with new and interesting discoveries.

NOTE: The latest version of the paper Tony Lavoie and I wrote on using lunar resources to create a cislunar space faring system has been published in the Proceedings of the AIAA Space 2011 Conference.  A copy is available for download HERE.

The Great White Fleet of the United States Navy, 1907 -- We need a fleet of spacecraft to open "This New Ocean" of space

We seem to be in one of those periods in which basic reasons for doing what we do as a nation are called into question.  This includes our national civil space program, which for the last few years has engaged in an extended period of back-biting and navel-gazing.  Much of this “debate” has focused on either or both of two points: what rocket to build and where to go, and not on sustainability.

In an era of limited resources, our challenge is to create a worthwhile space program with an expenditure rate that falls at or below a level perceived as affordable.  Given this reality (regardless of prevailing agency direction or assertions about projected deep space destinations) it is highly likely that cislunar space will be the sphere of space operations for the coming decade or two. Thus the questions should be:  What are we doing in space and why are we doing it?  If the answer is a series of space exploration “firsts” (flags-and-footprints forever), that model will require specific activities and missions.  If the answer is that an incrementally developed transportation infrastructure is desired, one that creates an expanding sphere of human operations, then such a model requires a different set of specific activities and missions.

Thus, the real debate is not about launch vehicles or spacecraft or even destinations; it is about the long-term – the paradigm or template of space operations.  One model requires mega-rockets to distant targets for touch-and-go missions; for convenience, I’ll call it the “Apollo” template (no denigration intended).  The other model is an incremental, go-somewhere-to-stay-and-then-expand-onwards mindset – call it the “Shuttle” template (again, same disclaimer).  The one that you adopt and follow depends on what purpose you believe human spaceflight serves.

Because Mars may harbor former or existing life, NASA has presumed that it is our “ultimate destination” in space.  In effect, the entire focus of the human spaceflight effort has devolved into a huge science project – “The Quest for Life” (which means finding pond scum, not ET).  Thus, debate about what to build, where to go and how to do it must be formulated towards attainment of Mars.

This unspoken assumption has been at the root of most space objective studies for the past 20 years.  Mars was the end point of President George H.W. Bush’s Space Exploration Initiative, President George W. Bush’s Vision for Space Exploration, of former Lockheed-Martin President Norm Augustine’s two reports, and a myriad of space groups and societies.  From the 1990′s to the present, a multi-billion dollar robotic campaign has sent mission after mission to Mars, each discovering that the red planet once had liquid water.  This mania for Mars and preoccupation with possible life there, has blinkered our perceptions of the space program and distorted our reality of what is possible or attainable on reasonable time scales with available resources.

Long term, the goal for human spaceflight is to create the capability to go anywhere we choose, for as long as we need, and do whatever we want to in space.  For the sake of argument, if one accepts such a goal, which model is more amenable to implementing it: the Apollo template or the Shuttle template?

If our goal is to “sail on the ocean of space,” we need a navy.  Navies don’t operate with just one class of ship because one class isn’t capable of doing all that is necessary.  Not all ships will look or operate the same because they have different purposes and destinations.  We need transports, way stations, supply depots, and ports.  In space terms, these consist of one to get people to and from space (LEO), one to get them to and from points beyond LEO, way stations and outposts at GEO, L-1, low lunar orbit, and to the lunar surface.  To fuel and provision our space navy, we require supply (propellant) depots in LEO, L-1 and on the lunar surface.  Ports of call are all the places we may go to with this system.  Initially, those ports are satellites in various orbits which require service, maintenance and replacement with larger, distributed systems.  Later, our harbor will be the surface of the Moon, to harvest its resources, thereby creating more capability and provisions from space.  Reliable and frequent access to the entire Solar System, not one or two destinations, should be our ultimate goal.

By designing and building mission-specific vehicles and elements, the “Apollo” template forfeits going everywhere and doing everything.  However, adopting the “Shuttle” model does not preclude going to Mars.  In fact, I contend that to go to Mars in an affordable manner that sustains repeated trips, one needs the infrastructure provided by a space faring navy.  Building a series of one-off spacecraft – huge launch vehicles to dash to Mars for expensive, public relations extravaganzas will eventually put us right back in the box we’re in now.

We have been arguing about the wrong things.  It is the mindset of the space program that needs re-thinking – not the next destination, not the next launch vehicle, and not the next spacecraft.  How can we change the discussion?  First, we need to understand and articulate the true choices so that people can see and evaluate the different approaches and requirements.  Second, we need to develop sample architectures that fit the requirements for “affordable incrementalism.”  Finally, we need to get such plans in front of the decision makers.  There is no guarantee that they will accept it or even listen to the arguments for it.  But right now, they are completely ignorant about it.

A cost-effective, sustainable human spaceflight program must be incremental and cumulative.  Our space program must continually expand our reach, creating new capabilities over time.  Moreover, it should contribute to compelling national economic, scientific and security interests.  Building a lasting and reusable space transportation system does that, whereas a series of PR stunt missions will not.  The original vision of the Shuttle system was to incrementally move into the Solar System – first a Shuttle to-and-from LEO, then Station as a jumping off platform and then beyond LEO into cislunar space.  We have the parts from the now retired Shuttle system and an assembled and working International Space Station.  We can use these legacy pieces to build an affordable system to access the near regions and resources of cislunar space.  In this new age of austerity, perhaps we will finally acquire the means to build our pathway to the stars.