Resource Development of Near Earth Asteroids
Andrea Nowicki, Brian Carlson, Kamala Butler
Asteroids: Characteristics and Classifications
Main Belt Asteroids:
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millions of asteroids from 2-4 AU
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orbital periods of 2.8 to 8 years
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sizes range from 940 km down to dust
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pieces of a planet that never formed
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Kirkwood gaps
Composition of Asteroids:
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all contain rock and volatiles
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some contain ice and valuable metals
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type S-stony iron, type C-carbonaceous, type M-pure nickel
iron metallic are the three most common groups
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differentiation
Near-Earth Asteroids:
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Apollos, Atens, and Amors
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there are 502 known NEAs as of May 24, 1998 (MPC)
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Apollos and Atens are the closest, most dangerous, and
most economically attractive.
Formation of the Near-Earth Asteroids:
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most orignated in main belt
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perturbations and collisons bring them into the inner
solar system
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captured comets
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therefore, the largest NEAs are on the order of 1km in
diameter
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all characteristics of main belt represented except large
size
Near-Earth Asteroid Mining: What and How
Mining Practices on Earth
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2ppm
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environmentally devastating
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differentiation trapped 99.9% of our gold, rhenium, and
platinum group metals in the Earth's core (Kargel, p.50)
Asteroids
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As much as 300ppm
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little or no differentiation
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Close proximity (at particular times)
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Very little gravity
Process
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Robotic missions
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Metals extracted from crushed rock through centrifuge
or electromagnets
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Because of the lack of gravity the process of mining as
well as transport is easier
Applications
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Precious metals could be profitabily brought back to Earth
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Near-term: LEO space technologies: SPSs, communication
satellites, rocket propellants, and life support materials
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Solar Power Satellites (SPSs): clean energy generation
(benefits from the Sun's full energy 24 hours a day)
Ethical Considerations:
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Should we exploit the resources of space? Why or
why not?
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Is there a difference between mining an asteroid, a place
without life or ecosystems and mining Earth?
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Is the mining of asteroids a continuation of a disposable
consumerist mindset? Or does the utilization of space resources have
the potential to solve some of our environmental problems? (Clean
energy generation & reduction of detrimental terrestrial mining)
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What would constitute a fair environmental ethic for space?
Which countries will be involved in creating this ethic (the U.N.)?
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Can the research that goes into mining asteroids help
increase our ability to defend ourselves against an impact by increasing
our knowledge?