Archive for July, 2009

Space exploitation instead of exploration!

2009/07/17

Most people who are space exploration advocates believe that Mars is the big goal for the foreseeable future.  They talk about colonizing the red planet, terraforming it so that humans can walk under the open sky without protective equipment, and establishing a back-up culture for the one on Earth.  Many of these people believe that we should be sending humans to Mars right now, in spite of all the things that we don’t know about Mars, the long transit times to go there and back, (about 6 months each way,) and the fact that we have never developed a self-contained life support system.

A lot of these folks bristle at anything which they perceive delays going to Mars, or diverts resources from a Mars mission.  Some of them are quite opposed to sending people back to the Moon, because they don’t believe that the Moon has anything to offer humanity.  They want everyone to pay for making their dream a reality, with no thought of any other applications for space flight.

If the only reason to invest in space flight were the colonization of other planets, we would be a long time getting off of Earth.  Fortunately, there are other reasons to put money into space technology, reasons that are likely to generate extensive investments off planet.  The constant search for new products will be one driver, and the escalating costs of extracting resources and processing them here on Earth will be another.

We will be able to do things in space that simply can not be done here on Earth, because of gravity.  In a weightless environment, it is possible to mix oil and water, and have them stay mixed.  We probably don’t need any mixtures of oil and water, but that illustration demonstrates that in zero-gravity, density differences don’t have any effect.  So, we will be able to create new alloys,  because we can mix two metals with very different densities together, and they will not separate before they cool.

This effect also means that we can make foams out of almost anything, such as aluminum, steel, or any other metal, or even ceramics, because the bubbles will not rise to the top before the material cools.  And keeping some materials from cooling quickly makes them much stronger, through a process called annealing.  By keeping steel, for instance, at a high enough temperature for a long period of time, the crystalline structure of the metal is able to properly align itself all through the material.  This makes any steel item properly annealed much stronger than an item which is allowed to cool fairly quickly.  By ‘fairly quickly,’ I am talking days, not hours.  To anneal a steel wrench might take several weeks, which requires huge amounts of energy.

But that energy is free in space, so there is no prohibitive cost in annealing.  Extracting aluminum from bauxite is extremely energy-intensive, but we can tap the huge resources of the Sun in space, and create temperatures which are will allow the smelting of any ore, without having to burn anything in the Earth’s atmosphere.  The Moon is made up of nearly the same things as the Earth is, so we can find precious metals like copper, titanium, and gold on the Moon, extract them, and purify them, all without doing any damage to the Earth’s environment.

These are the reasons that big business will invest in space exploration, not building colonies on distant planets.  But the investments that big business makes will pave the way for the colonists, by creating more efficient launch systems, building Orbital Transfer Vehicles to move payloads around in Earth orbit, and developing ways to protect people from radiation, always a hazard when in space for long periods of time.

Encouraging business to invest in off-planet development, aerospace technology, and the study of zero-gravity processing will speed the exploration and colonization of the Solar System, by making available much sooner the technology needed to get large payloads off of Earth,  as well as people in a safe and reliable manner.

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