Mars
- Pro: Because it's there.
- Con: Very little there.
- Con: Hellishly expensive to get there.
- Con: Nothing leaves (so far).
Very Little There |
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|
units |
Earth |
Mars |
Ratio |
Distance (avg) |
AU |
1.0 |
1.52 |
1.52 |
diameter (avg) |
km |
6371 |
3290 |
0.52 |
Resources |
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atmosphere mass |
kg |
5.2e18 |
2.5e16 |
0.005 |
water mass |
kg |
1.4e21 |
5e18 |
0.004 |
gravity |
gee |
1.0 |
0.38 |
0.38 |
note: Mars "water" mass may be smectite clay |
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|
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total insolation (diameter/distance)^2 |
0.12 |
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lethal perchlorates |
not yet |
yes |
∞ |
|
cosmic rays |
rem/y |
0.03 |
10 to 20 |
500 |
Phobos and Deimos are zero for the ratios, but 6 to 8 km/s easier to visit then return. 3 meters of local regolith shielding can easily be supported by a 6 psi (50/50 oxygen/helium ) balloon containing a 1 gee rotating habitat.