Sunday, 30 June 2019

Interplanetary mining


 There is plenty of room on the earth but humanity is now too demanding of resources and environment to sustain its expansion mode. 

Artificial intelligence and robotics have grown up very rapidly  and this kind of technology is enormously useful in space exploration but like most modern technology it requires minerals and metals. A recent article in The Week (22 June, 2019, p.13)

Rare Earths: China's Secret Weapon? 

highlights the potential geopolitical ramifications of the shortage of the 15 lanthanoid elements (La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu) together with scandium and yttrium, known collectively as the 'rare earths'. 

They are geographically widely dispersed as well as difficult and energy intensive to extract, a process which causes waste disposal and pollution problems and a very low quality of life for those forced to work in the mines as well as those living nearby.

 
There is an increasing shortage of minerals and metals needed in technology, especially in China, an inevitable consequence of



  • A rapidly growing world population. Every hour there are some 9000 more people alive on the planet, all consuming resources and generating waste at a growing rate

  • A rapidly growing per capita demand for technology (GDP growth 5.9% p.a. means more money spent on goods and services which draw upon the Earth's  resources)

TThis investor report states that ‘dysprosium, terbium, europium, neodymium and yttrium are critical and face a looming shortage. These rare earth elements and their associated compounds are used in solar panels, fluorescent bulbs, electric car batteries, wind turbines and semiconductors. Platinum (Pt) and related metals are also in short supply and more expensive than gold.  Most of the world supply of Pt is used in catalytic converters and fine jewellery.

Yttrium (Yt) , europium(Eu) and  terbium (Tb) are used as phosphors in smart phone and TV screens. Lanthanum (La) is used in the batteries of hybrid cars (10 kg per battery). Rare earth elements are widely used in green technology, headlights, catalytic converters, oil refineries, lasers, camera lenses, X-ray machines, MRI scanners, nuclear reactors.  Electric motors in hard disk drives, power tools and electric cars rely on powerful magnets using neodymium (Nd) and praseodymium (Pr) alloys.

Iridium (Ir) is distributed thinly over the planet and expensive to mine, yet is in demand for its uniquely high resistance to oxidation, and as a hardening agent in alloys when combined with Pt and osmium (Os). Pt-Ir alloys are also in sparking plugs and Pt-Os alloys are used to tip fountain pen nibs, in pivot bearings such as those found in compasses, and in surgical tools.




In the past the supply of these materials has been more than enough. This would not have been the case if the Earth did not have such a variety of minerals: 4,500 vs 60 for the average rocky planet (secondary data I came across in 2012; from the source I have no reason to believe it is in any way misleading. I will try to find an up to date link) brought to near the surface and within reach of civilisation by plate tectonics (again, of a kind unique to the Earth).


Providentially, all these substances are available in abundance in asteroids, which are now within reach of humankind at just the right time in history that they are needed and when we are close to developing the know-how to reach them. (The Christian in me says 'Praise the Lord' and I hope God-deniers or ignorers will forgive this lapse of secular etiquette!). In fact we already rely mostly on past impacts from space for our supply of Pt. Even gold is heavily reliant on an asteroid which fell to Earth where the mines of Johannesburg are located today. Some asteroids comprise stainless steel, so pure that it requires no refining. Again, at least one extraterrestrial source has been used on Earth: the Inuits in NorthAmerica made tools and knives out of unrefined metals from meteorites. And Sudbury, Ohio is a mining town exploiting nickel, copper and other metals derived from an ancient impact.


So now is the time to start proactively seeking out this abundant resource rather than wait for the biosphere to be strained beyond its limit. A company has already been formed with just this objective: Planetary Resources Inc., https://www.planetaryresources.com/). The current website states there are 16,000 asteroids rich in resources, 2 trillion tonnes of water for life support and fuel, and that space exploration costs in the long term could be reduced by 95%.

It was set up by James Cameron (adventurer and film director) and Larry Page (co-founder of Google with Sergery Brin), who were able to put serious money into it – billions of dollars. It is being done as a money making venture, its viability deriving largely from the high and increasing price of platinum.  


Requoting from its website as of 2012: Some near-Earth asteroids contain platinum group metals in much higher concentrations than the richest Earth mines. In space, a single platinum-rich 500 meter wide asteroid contains about 174 times the yearly world output of platinum, and 1.5 times the known world-reserves of platinum group metals (ruthenium, rhodium, palladium, osmium, iridium, and platinum).’ It is not just the very expensive materials that are being targeted. Quoting again from Planetary Resources: ‘Asteroids also contain more common metallic elements such as iron, nickel, and cobalt, sometimes in incredible quantities. In addition to water, other volatiles, such as nitrogen, CO, CO2, and methane, exist in quantities sufficient to warrant extraction and utilization.’


They are intending to park asteroids in orbit around either the Moon or the Earth. If the former they would choose ones having a large amount of ice since this could be used to support a lunar colony with water or the electrolysed components of water – hydrogen for fuel, oxygen for breathing. This would be a kind of contracted service for any number of manned lunar enterprises. Minerals could be sent back to Earth relatively cheaply and there are plenty of comet-like bodies having both ice and rock.  Platinum-rich bodies could be parked in Earth orbit for a good financial return.


The stainless steel asteroids, which can provide steel of higher grade than that from steelworks, could be used both on the Earth and for the building of spacecraft and space stations in orbit or at L2 Lagrange points. Iron and aluminium could also be used for construction work in space.


Not surprisingly, NASA is interested as, I suspect, are the space agencies of Europe, Russia, Japan and China.


Our planet is becoming overstretched not because of people per se but because of the resources they consume and the waste this generates. Equally important is a lack of awareness of just how precious it is and I believe that starting up major enterprises in the hostile environment of space, together with the rarity, if not the non-existence, of extraterrestrial life, will shock us into facing the reality that we and our world are special.

See also
 Destination Phobos?

There is also a technology in the UK awaiting investment which could reduce the cost of launching a payload into orbit by an order of magnitude. This uses a revolutionary propulsion that has gone through proof of concept test, SABRE)
See
Skylon: an opportunity for a venture capitalist?

John

cosmik.jo@gmail.com