I am having fundamental difficulty in feeling the definition of specific intensity of a radiation field...
questions:
1) Define a radiation field as precisely as possible.
2) Specific intensity defined at a point should remain the same whichever way we choose for the differential surface...
Mining and manufacturing on the moon:
http://aerospacescholars.jsc.nasa.gov/HAS/cirr/em/6/6.cfm
we are not faraway from the day before we can inhabit the moon..
He-3 as a fuel..
Iron manufacturing units..
46% oxygen in the crust
Polar ice..