https://blogs.scientificamerican.com/guest-blog/lets-colonize-titan/
Up to now, most researchers have looked at the Moon or Mars as the next step for human habitation. These destinations have the dual advantages of proximity and of not being clearly unrealistic as choices for where we should go. That second characteristic is lacking at the other bodies near us in the inner solar system, Mercury and Venus.
Mercury is too close to the sun, with temperature extremes and other physical conditions that seem hardly survivable. Venus’s atmosphere is poisonous, crushingly heavy and furnace-hot, due to a run-away greenhouse effect. It might be possible to live suspended by balloons high in Venus’s atmosphere, but we can’t see how such a habitation would ever be self-sustaining.
But although the Moon and Mars look like comparatively reasonable destinations, they also have a deal-breaking problem. Neither is protected by a magnetosphere or atmosphere. Galactic Cosmic Rays, the energetic particles from distant supernovae, bombard the surfaces of the Moon and Mars, and people can’t live long-term under the assault of GCRs.
The cancer-causing potential of this powerful radiation has long been known, although it remains poorly quantified. But research in the last two years has added a potentially more serious hazard: brain damage. GCRs include particles such as iron nuclei traveling at close to the speed of light that destroy brain tissue.
Exposing mice to this radiation at levels similar to those found in space caused brain damage and loss of cognitive abilities, according to a study published last year by Vipan K. Parihar and colleagues in Science Advances. That research suggests we aren’t ready to send astronauts to Mars for a visit, much less to live there.
On Earth, we are shielded from GCRs by water in the atmosphere. But it takes two meters of water to block half of the GCRs present in unprotected space. Practically, a Moon or Mars settlement would have to be built underground to be safe from this radiation.
Titan is the only other body in the solar system with liquid on the surface, with its lakes of methane and ethane that look startlingly like water bodies on Earth. It rains methane on Titan, occasionally filling swamps. Dunes of solid hydrocarbons look remarkably like Earth’s sand dunes.
For protection from radiation, Titan has a nitrogen atmosphere 50 percent thicker than Earth’s. Saturn’s magnetosphere also provides shelter. On the surface, vast quantities of hydrocarbons in solid and liquid form lie ready to be used for energy. Although the atmosphere lacks oxygen, water ice just below the surface could be used to provide oxygen for breathing and to combust hydrocarbons as fuel.
It’s cold on Titan, at -180°C (-291°F), but thanks to its thick atmosphere, residents wouldn’t need pressure suits—just warm clothing and respirators. Housing could be made of plastic produced from the unlimited resources harvested on the surface, and could consist of domes inflated by warm oxygen and nitrogen. The ease of construction would allow huge indoor spaces.
