| Ne, ppm | 5.0 | 2.0 | 2.0 | 2.0 | - | 1.0 | - | 2.0 | - | - |
| Ni, ppm | 206 | 131 | 189 | 146 | 174 | 345 | 208 | 321 | 282 | 286 |
| Os, ppb | 14.0 | - | 6.0 | 1.79 | 30.0 | 22.0 | - | - | - | - |
| Pb, ppm | 2.9 | .80 | 4.8 | 1.033 | 6.0 | 2.58 | 1.15 | 10.02 | 2.5 | 1.922 |
| Pd, ppb | 21.0 | - | 9.7 | 6.2 | - | 24.0 | - | 50.0 | - | - |
| Pr, ppm | 7.7 | - | 10.1 | 3.8 | - | 4.97 | 4.0 | 23.0 | - | - |
| Rb, ppm | 3.0 | 1.2 | 7.28 | 2.70 | 1.85 | 2.48 | 1.65 | 15.25 | 5.0 | 4.21 |
| Re, ppb | 5.26 | .47 | .34 | .39 | .36 | .82 | 3.19 | 1.15 | - | - |
| Rh, ppm | .1 | - | .4 | - | .077 | - | - | - | - | - |
| Ru, ppm | .6 | - | .047 | - | .046 | .010 | - | - | - | - |
| Sb, ppb | 4.1 | 25.4 | 47.0 | 30.0 | 3.8 | 9.7 | 5.7 | 3.4 | - | 26.0 |
| Sc, ppm | 62.8 | 65.0 | 39.2 | 37.1 | 39.9 | 8.9 | 17.0 | 21.9 | 22.0 | 18.0 |
| Se, ppm | .39 | .27 | .30 | .18 | .39 | .24 | .30 | .031 | - | .23 |
| Sm, ppm | 11.7 | 8.0 | 20.3 | 5.85 | 8.8 | 5.38 | 3.39 | 30.9 | 9.6 | 8.1 |
| Sn, ppm | .7 | - | .3 | - | 1.7 | .22 | .8 | - | - | - |
| Sr, ppm | 193.0 | 166.0 | 138.9 | 104.2 | 234.0 | 168.0 | 140.8 | 183.8 | 152.0 | 150.0 |
| Ta, ppm | 1.5 | - | 1.58 | .55 | 1.4 | .50 | .50 | 4.1 | 1.05 | .87 |
| Tb, ppm | 3.3 | 2.63 | 4.07 | 1.4 | 1.5 | 1.07 | .80 | 6.4 | 4.2 | 1.72 |
| Te, ppm | .07 | .01 | .05 | - | .088 | .023 | .051 | .031 | - | - |
| Th, ppm | 2.24 | .82 | 6.63 | 1.76 | 1.07 | 1.87 | 1.44 | 13.5 | 4.15 | 3.01 |
| Tl, ppb | 2.1 | 1.4 | 2.0 | .94 | 1.6 | 7.7 | 6.2 | 22.0 | - | 2.4 |
| Tm, ppm | 1.5 | - | 2.02 | - | .73 | .67 | .41 | 3.9 | - | - |
| U, ppm | 1.37 | .26 | 1.61 | .483 | .300 | .52 | .45 | 3.48 | .99 | .90 |
| V, ppm | 66 | 128 | 110 | 191 | 73.5 | 25.5 | 38 | 49 | 84 | 52 |
| W, ppm | .24 | .14 | .74 | .31 | - | .31 | - | 1.9 | - | .52 |
| Y, ppm | 107 | 74 | 145 | 47 | 48 | 39.3 | 49 | 242 | 73 | 64 |
| Yb, ppm | 10.6 | 7.48 | 13.7 | 4.53 | 5.59 | 3.86 | 2.40 | 22.7 | 7.3 | 6.15 |
| Zn, ppm | 23.0 | 49.0 | 6.3 | 12.8 | 25.0 | 24.0 | 34.1 | 28.0 | 14.5 | 20.0 |
| Zr, ppm | 331 | 236 | 503 | 175 | 308 | 163.8 | 192 | 842 | 278 | 262 |
aMajor elements (>0.1%) are reported first as both the usual oxide notation and elements. Data compiled from the Data Base Compilation of the Lunar Sample Curator, NASA Johnson Space Center, Houston, Texas.
Terrestrial materials. Progressive developments of more efficient Earth-to-LEO boosters are expected to reduce transport costs eventually to at least $10-20/kg, comparable to the price of transoceanic air travel (Akin, 1979). The major tradeoff is between development costs of new launch systems and rates of transport in t/yr. Thus, Earth-to-LEO shipment of higher-value products (above $10/kg) needed in low annual tonnages is acceptable and should not seriously restrict the growth of space industries (Criswell, 1977a, 1977b). Space manufacturing directly leverages the effectiveness of any system for transporting goods and materials off-Earth if the value added to the space products is less than the value added by launch of functionally similar goods from Earth (Goldberg, 1981).
STS components such as exhausted hydrogen/oxygen propellant tanks call be used for raw materials. Shuttle external tanks could provide approximately 140 kg/hr of alumina and 10 kg/hr of other elements (e.g., plastics, residual propellants) for early development of manufacturing procedures and products, assuming 30 Shuttle flights per year. (See sec. 4.4.2.)
Earth's upper atmosphere also may prove a valuable source of nitrogen and oxygen for use at LEO and beyond. At 200 km altitude a scoop 1 km in radius oriented perpendicular to the orbital motion intersects approximately 4 t/hr of molecular nitrogen and 3 t/lir of atomic oxygen. Physical convergent nozzles might be used to collect either N2 or 0+, and a convergent magnetic field might be employed to recover O+. Power must be supplied to liquefy the gases and to accelerate a portion of the gathered material to maintain orbital velocity.
Lunar resources. Table 4.1 lists major oxides and elements found in samples of the mare and highland areas of the Moon and returned to Earth during the Apollo and Soviet programs. Table 4.2 summarizes the major lunar minerals and the general uses to which each could be put (Arnold, 1977). The Moon is extremely rich in refractories, metals (Fe, Mg, Ti, Al), oxygen and silicon. Extensive
