Gold coins? Platinum pellets? Grains of cobalt? I predict water will be the preferred currency in outer space. You can drink it, bathe in it, breathe it (oxygen), burn it in rocket engines (oxygen and hydrogen), grow things (hydroponics), and protect yourself from radiation.
Water is easily stored, shaped, and divided up for transactions. It can be flash frozen and quickly thawed with the deep cold of space and the intense radiation of the Sun.
The current method of water storage in space looks like duffel bags with a spout as this picture reveals. This astronaut is obviously reveling in the fortune of water surrounding him. That water is worth $83,400 per gallon based on the current cost of $10,000 to put a pound of something into orbit. Hopefully, it is Evian or Fuji.
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| Water storage aboard ISS - Courtesy NASA |
Or one could build a palace of ice in outer space. There is that much water available on some asteroids. Just make sure the seal between the ice and the airlock stays frozen solid.
Small entrepreneurs will make their first fortunes by seeking out chunks of ice in the asteroid belt or simply mining close-flying asteroids for the liquid gold. Planetary Resources, an actual asteroid mining company, has recently stated that it will concentrate on water instead of precious metals as its first acquisition.
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| Water globule floating on ISS - courtesy NASA |
The companies that first acquire water in space will be like the merchants that made fortunes selling picks and shovels to the forty-niners in the California gold rush.
The importance and value of water will demand that water recycling and reclamation units aboard space vehicles and habitats be ubiquitous and efficient. Even if someone dies in space, the water in their body will be reclaimed before burial in space or transportation back to Earth. This will be part of a signed agreement when someone goes to work in space. Their immediate kin will get some portion of the value of that water in space, even if they are on Earth.
Security will be a concern as well. When a worker’s contract ends, what’s to keep him from filling flexible bags of water and hiding them about his body and carry-all? When he gets back to the orbiting end of the Lunar Space Elevator or a space station near Earth, he turns his water in for some Earth-based currency like gold or platinum before going back to the planet.
The biggest non-recoverable expenditure of water in space will be for rocket fuel. The biggest recoverable use for water in space will likely be radiation shielding. It is efficient over a spectrum of radiation including cosmic and gamma rays. In fact, radiation shielding may be designed to not only protect against radiation but to be a reserve source of fuel as well.
It is possible a water-based currency, both physical and digital, will be established in a space-based culture of dozens of companies and thousands of workers. Since water melts so readily, the gold coins, platinum pellets, or grains of cobalt mentioned before might actually be used; and they will represent some predetermined amount of water. That amount will most likely be decided by some committee with all of the space-based companies represented. The value of water will fluctuate as discoveries are made on asteroids being mined and unrecoverable expenditures of water such as rocket fuel are used up. There may one day be a cryptocurrency based on water - H20coin, of course.
The actual water will be kept in some safe place, a giant chunk of ice hidden, or well-guarded, or both. As a matter of course, owners of large quantities of water in space will, at some point, have that water melted and mixed with some small amount of radioactive isotope to “brand” it. It won't be enough to affect health, but it will be easy to track if it is stolen.
There is probably more water in asteroids than on Earth. Its value in space comes from the difficulty and expense of finding and securing it. Those who do this first will be the future lords and princes of outer space. They will control the lifeblood of space.
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