We Have Been Mining Asteroids for Years, Just Not in Space - But That Will Have to Change

Mr. Gary Bickford's picture

Experts and laypeople have been discussing the potential, the risks, and the economics of asteroid mining for a long time.  What most people don't realize is that we've been mining asteroids all along.  But up until now, we've been able to get by with the previous deliveries from space; now we need to consider a new delivery system as the stockpiles are reduced, and the impact on our living space becomes increasingly important.  Mining of asteroids and the Moon _will_ become an essential part of our civilization, unless it collapses before we get there.

As population and industrialization continue to grow, we are outstripping these available in-ground resources just as we are of more mundane things that make the news.  Lately the talk has been about oil, coal, and gas - so-called "fossil fuels".  These materials are all relatively lightweight and will mostly never sink into the depths of the Earth - they will be recycleable forever, if we handle them well.  But that is not true of these other essential heavy metal resources.

"Based on known terrestrial reserves, and growing consumption in both developed and developing countries, key elements needed for modern industry and food production could be exhausted on Earth within 50–60 years.[2] These include phosphorusantimonyzinctinleadindiumsilvergold and copper.[3] In response, it has been suggested that platinumcobalt and other valuable elements from asteroids may be mined and sent to Earth for profit, used to build solar-power satellites and space habitats,[4][5] and water processed from ice to refuel orbiting propellant depots.[6][7][8]

In fact, nearly all the goldcobaltironmanganesemolybdenumnickelosmiumpalladiumplatinumrhenium,rhodiumruthenium and tungsten mined from Earth's crust, and that are essential for economic and technological progress, came originally from the rain of asteroids that hit Earth after the crust cooled.[9][10][11] This is because although asteroids and Earth accreted from the same starting materials, Earth's relatively stronger gravity pulled all heavy siderophilic (iron-loving) elements into its core during its molten youth more than four billion years ago.[11] This left the crust depleted of such valuable elements[11] until asteroid impacts re-infused the depleted crust with metals (some flow from core to surface does occur, e.g. at the Bushveld Igneous Complex, a famously rich source ofplatinum-group metals)." - Wikipedia

We are in not-quite-imminent threat of restricting the growth of modern industrial society, and failure to bring the rest of humanity out of dirt-poverty, if we can not provide these metals and other elements in sufficient quantity.  Not everything can be made of plastic, and even plastics manufacturing requires many of these.  Platinum has been in the news due to its present extremely high price and potential as the first asteroid-mining target, but many other metals will become increasingly important in the future, including many obscure ones such as technetium, gadolinium, and indium. Nearly every industrial process requires one or more of these elements.  For example, many industrial and food manufacturing processes depend on pure nickel piping for resistance to corrosion and product purity.  That piping may include chromium, niobium, molybdenum, and other metals as alloy constituents.  Many more examples can be cited.

As the above citation describes, A substantial amount of many important industrial metals is of relatively recent asteroid origin - i.e., it arrived here via asteroid impact long after the Earth had cooled enough to have a floating crust.  The vast majority of the denser ("heavier") metals that were among the early Earth's consituents sank into the molten mass and now reside in the core, where they will remain until the demise of the Earth itself.  The famous Chixcolub crater, associated with the demise of the dinosaurs 66 million years ago, is associated with a thin layer of clay with high levels of iridium found all over the planet.  It is believed that this iridium was a constituent of this asteroid, and was blown into the atmosphere along with much of the asteroid's material and large quantities of clay and steam as a result of the impact.

There are multiple factors in the question of mining asteroids in space - here on Earth, the economics and the negation or amelioration of the problems of mining the Earth's surface are primary.  In space, these materials will be essential to manufacturing, both for trade and for development and habitation.  It is unlikely that bringing iron or nickel back to Earth from asteroids will be economically practical for the foreseeable future - except as components of vehicles returning other goods of course! But it is almost inevitable that a panopoly of new technology products, such as integrated circuits produced in the vacuum and microgravity of space using methods that are impossible on Earth, will become major new additions to our quality of life on Earth, and essential trade goods as a true space-inclusive economy arises.  The biggest confounding factor is that our knowledge is almost all based on remote sensing and very sophisticated physics.  This article from Brightweb is an intro to the basiics.

A little-discussed question is space poilution.  Will space mining and manufacturing result in 'dirty skies'?  That's a question for a later blog, but should not be ignored.

Comments

Brent Shambaugh's picture

Gary,

How do you think landfill mining will change the necessity of asteroid mining?

https://en.wikipedia.org/wiki/Landfill_mining

-Brent

Mr. Gary Bickford's picture

It seems reasonable to expect that landfill mining will be increasingly important in the short term, as our past profligacy becomes the target of more economical recovery technology.  The logical resul of this can be seen by analogy in the Amazon rain forest, where (as I once read), nearly all the nutrients are bound up in the living things, and the dirt is almost completely bereft of nutrients.  Similarly, at some point the landfills will have been processed, and recyclables technology will make it possible for almost everything we use to be reprocessed almost immediately and reintroduced into the new product stream.

But this will not be enough.  To the extent that this is feasible, all the contents of existing landfills (and computer graveyards, and ship breaking yards, etc.) will eventually be reprocessed and brought into the stream.  But all of that material was the result of the middle class lifestyle of a small proportion of the world's people, perhaps 10 or 20 percent.  If resource utilization per GDP were to continue as in the past, this would mean that we would need five or more times as much of all the resources used so far, to accomplish this expanion.  While resource utilization efficiency continues to improve, as the rest of the world desires to move up to a similar lifestyle, even with all the recycling, the total amount of many resources will still not be enough to meet this demand.

In order to meet the demands of a future middle class world, and reduce or eliminate polluting industries such as mining and smelting of nickel (which presently causes complete devastation of hundreds of square miles surrounding the processing facilities), these materials can and must be profitably, safely, and environmentally produced in space.  I'll just point out one example, the Sudbury Basin, a major Platinum source, is in fact a meteorite impact crater.