(August 4, 2019 at 5:35 pm)sdelsolray Wrote: Venus' lack of a magnetic field, it's near perpendicular axis tilt of only 3 degrees (actually 177 degrees from its north pole) and its extremely long rotational period of 243 days are additional stumbling blocks to terraforming it to support carbon-based life.
None of those should present insurmountable difficulties.
1. The low rotation rate means natural day night cycle would be extremely long and, if the atmosphere is dramatically thinned until surface pressure begins to resemble those earth, the day-night temperature difference may become very high. However, this may be offset by sunshade and sun reflectors In orbits with periods similar to earth day night cycle.
2. Lack of magnetic field - this allows solar wind to strip the upper atmosphere. However, even if Venus to the atmosphere is reduced to earth atmospheric mass, the time required to strip away most of Venusian atmosphere is still on the order of hundreds of millions of years. In other words it needn’t stop us in the next few hundred or few thousand years. Atmosphere stripping will also strip away UV-B deflecting ozone, however that needn’t be a serious issue at high latitudes where angle of incidence would dramatically reduce intensity of uv to reach surface. Lower latitudes on even terraformes Venus would likely remain uninhabitable due to the fact that solar constant on Venus is twice that on earth. Intensity of solar radiation at 60 degrees latitude on Venus would still be the same as that on equator on. So high latitudes (almost arctic circle latitudes were it on earth) would be the main livable locations on Venus. which brings us to axial tilt.
3. Lack of axial tilt- so Venus will have no seasons, not a show stopper by any means. However lack of axial means the 30 degrees of latitude around each pole of Venus won’t see half year long days or nights as polar regions do on earth. The area would still need artificially circadian rhythm, but so would any other part of Venus.
