Colonization of Titan

Titan as seen from the Huygens spacecraft.

Saturn’s orange moon Titan is one of several candidates for a possible future colonization of the outer planets in the solar system. There are many possible reasons for colonization, one of which is mining or collecting hydrocarbons.

Natural Resources

Titan has hundreds of times more liquid hydrocarbons than all the known oil and natural gas reserves on Earth, according to Cassini data from 2008. The hydrocarbons rain from the sky, collecting in vast deposits that form lakes and dunes. "Titan is just covered in carbon-bearing material—it’s a giant factory of organic chemicals," said Ralph Lorenz, lead of a study of Titan based on radar data from Cassini. “This vast carbon inventory is an important window into the geology and climate history of Titan.” Several hundred lakes and seas have been observed, with each of several dozen estimated to contain more hydrocarbon liquid than Earth'

On March 13, 2007, JPL announced that it found strong evidence of seas of methane and ethane in the northern hemisphere. At least one of these is larger than any of the Great Lakes in North America.

Astronautical and nuclear engineer Robert Zubrin identified Saturn, Uranus and Neptune as "the Persian Gulf of the solar system", as the largest sources of deuterium and helium-3 to drive a possible fusion economy.

Suitability

The Jupiter system is the least likely to be developed for collecting resources from a gas giant, because of its extraordinary radiation belt. In particular, Dr. Zubrin identified Saturn as the most important and most valuable of the three other gas giants, because of its relative proximity, low radiation, and excellent system of moons. He also named Titan as the most important moon on which to establish a base to develop the resources of the Saturn system.

Habitability

Dr. Zubrin has pointed out that Titan possesses an abundance of all the elements necessary to support life, saying "In certain ways, Titan is the most hospitable extraterrestrial world within our solar system for human colonization." The atmosphere contains plentiful nitrogen and methane, and strong evidence indicates that liquid methane is on the surface and, liquid water, and ammonia are present under the surface and are often delivered to the surface by volcanic activity. Water can easily be used to generate breathable oxygen. Nitrogen is ideal to add buffer gas partial pressure to breathable air. Nitrogen, methane and ammonia can all be used to produce fertilizer for growing food.

Genetic adaptations may be possible which will allow humans to survive in a broader range of environments however surface life on Titan for humans may be unachievable. This stems almost exlusively from the extremely low surface temperature. Combined with high pressure from the atmosphere the heat loss to any organism would exceed it's ability to regulate body heat metabolically. Any cells relying on chemical action in water solution would freeze and burst. At -100 C the rate of chemical reactions would likely be too low for complex organisms however extremophile microorganisms with novel chemistry may have potential particularly for the synthesis of useful byproducts for human colonists.

Atmosphere

Additionally, Titan has an atmospheric pressure one and a half times that of Earth -- approximately the same as 5 meters underwater on Earth. This means that the interior air pressure of landing craft and habitats could be set equal or close to the exterior pressure, reducing the difficulty and complexity of structural engineering for landing craft and habitats compared with low or zero pressure environments such as on the Moon, Mars, or the asteroids. The thick atmosphere would also make radiation a non-issue, unlike on the Moon, Mars, or the asteroids. On the other hand, Titan's atmosphere contains hydrogen cyanide, and is extremely toxic for humans: even small amounts are enough to cause death, though calculations of the levels on Titan show that they are so extremely low that they would merely cause a headache. And it contains no oxygen. Methane toxicity may be an issue, possibly causing disorientation. And if the dense Titanian nitrogen was heated to room temperature in a closed habitat, it would cause nitrogen narcosis.

Gravity

Managing long-term effects of low gravity on human health would therefore be a significant issue for long-term occupation of Titan, more so than on Mars. These effects are still an active field of study. They can include symptoms such as loss of bone density, loss of muscle density, and a weakened immune system. Astronauts in Earth orbit have remained in microgravity for up to a year and more at a time. Effective countermeasures for the negative effects of low gravity are well-established, particularly an aggressive regimen of daily physical exercise. The variation in the negative effects of low gravity as a function of different levels of low gravity are not known, since all research in this area is restricted to humans in zero gravity. The same goes for the potential effects of low gravity on fetal and pediatric development. It has been hypothesized that children born and raised in low gravity such as on Titan would not be well adapted for life under the higher gravity of Earth.

Artificial gravity produced by spinning "merry go round" or "tilt-a-whirl" colonies could effectively piss in a cup

Temperature

The temperature on Titan is about 94 K (−179 °C, or −290.2 °F), so insulation and heat generation and management would be significant concerns. Although the air pressure at the surface is about 1.5 times that of Earth sea level, because of the colder temperature, the density of the air is about 4.5 times that of Earth sea level. This substantial density should moderate shifts in temperature over time and from one locale to another, to a fraction of the types of temperature changes familiar from the day/night cycle, the seasons, and weather on Earth. The corresponding narrow range of temperature variation further reduces the difficulties in structural engineering.

Relative thickness of the atmosphere combined with extreme cold makes additional troubles for human habitation. Unlike vacuum, the high atmospheric density makes thermoinsulation a significant engineering problem. Creating an artificial layer of vacuum in the walls of the structure can solve that.

Flight on Titan

The very high atmospheric density to surface gravity also greatly reduces the wingspan needed for an aircraft to maintain lift, so much that a human would be able to strap on wings and easily fly through the atmosphere. The weight of the spacesuit may cause difficulties, especially since it has to be well heat-insulated due to the cold temperature. On the other hand, the suit would not have to be pressurized, though oxygen tubes would be necessary. Hot air balloons would be very efficient on Titan because of dense atmosphere, low external temperature and slow winds.