Wednesday, July 19, 2017

Mining the asteroids: how desperate can we become?



A silly idea that seems to be coming straight from a science fiction story of the 1950s. Mining the asteroids wouldn't just be outrageously expensive; the problem is that there is nothing to mine there. Yet, some people seem to take the idea seriously



It seems that, when we are in trouble, we tend to revert to our childhood memories, seen as happy times that, somehow, could return. That may explain why President Trump is dreaming of an impossible return to coal. He may see the idea through his memories of childhood as a time of happy miners and prosperous families.

Some others, instead, may revert to memories influenced by the science fiction of the 1950s, when the idea of "mining the asteroids" was commonplace. Jerry Pournelle wrote a delightful essay on this genre in 1980 under the title "Those Pesky Belters and Their Torchships". You may also remember the 1981 movie "Outland" starring Sean Connery and taking place in a mine on the moon of Jupiter, Io.

Nice memories, yes, could we ever mine space bodies for real? Well, the science fiction of the 1950s described many innovations that never appeared in the real world and most likely never will. Some because they are too expensive (flying cars) and some because they are contrary to the laws of physics (anti-gravity). Mining the asteroids falls straight into the "impossible" category for two reasons: the first is that it is too expensive and the second that it goes against the laws of geology (if not of physics). It wouldn't be physically impossible to mine the asteroids but there is nothing interesting for us to mine there.

Let me explain: we can extract minerals on Earth because of the "energy credit" that comes from geological or biological processes (and often both) which have concentrated specific elements in some special regions of the crust. We call these regions "deposits" and we use the term "ores" for those deposits which are concentrated and pure enough that they can generate an economic profit from mining. Only ores are a useful source of minerals. Mining from the undifferentiated crust is simply unthinkable because of the enormous energy it would require (see my book "Extracted").

And there lies the snag with asteroids. The physical processes that created ores on our planet can take place only on planets which are both geologically and biologically active. As far as we know, asteroids never were. So, there are no ores on asteroids; nor there are on the moon or other "dead" space bodies. It is not impossible that there could be ores on Mars, which may have been geo-biologically active in a remote past, or perhaps on the moons of Jupiter, maybe geologically active today. But, for what we know, the best place in the solar system where to find ores is our planet, the good, old Earth (and, incidentally, as science fiction goes, the 2011 movie "Cowboys and Aliens" got the geology of the story perfectly right: the aliens come to Earth for its mineral resources). 

So, no ores, no mining. And no ores on asteroids means no mining on asteroids (*). Of course, many asteroids are mainly iron, but it makes no sense to go there to mine iron if you consider that there is plenty of iron on Earth and you think of the costs involved with the idea of mining space bodies. It is an idea that just makes no sense.

Yet, we are seeing a spate of news that we could take as if someone really wanted to mine the asteroids. Possibly the most idiotic one appeared on "Futurism.com" with the title mentioning an asteroid "worth 10,000 trillion dollars". It seems that the author simply multiplied the mass of the asteroid, supposed to be all iron, by the current cost of iron per kg, arriving at such a meaningless number.

Other people seem to be peddling space mining and they may ask you money to finance their ideas on the basis of cute drawings which, indeed, remind the fictional spaceships of the 1950s. Others, including the Luxembourg government, seem to be willing to do exactly that: spend money on the idea of mining space, really!  (at least, despite their attempt of selecting the worst possible ideas they couldn't imagine, they don't seem to be planning to invade Iraq).

Some people who should know better seem to have lost track a little of what they are saying. So, the French astrophysicist Jean-Pierre Luminet is reported to have declared that "Asteroids are full of pure and precious metals, such as gold, platinum, cobalt, etc, in quantities ten to a hundred times larger than what we can find in terrestrial mines." (let's just say that we can't pretend that astrophysicists know something of geology).  The idea seems to be diffusing and I reported in a previous post how an acquaintance of mine reacted to my statements that we had resource problems with "but we shall colonize other planets!"

So, what to say? Just that when desperation sets in, idiocy often follows.




(*) commenter Ned noted that some meteorites have a platinum concentration higher than that of terrestrial ores. So, there may be an exception to the rule. Whether these asteroids could be actually mined, it is another question. 


Who

Ugo Bardi is a member of the Club of Rome, faculty member of the University of Florence, and the author of "Extracted" (Chelsea Green 2014), "The Seneca Effect" (Springer 2017), and Before the Collapse (Springer 2019)