This is a simulation of what one would expect to find on a terraformed Titan, using formulas from Math And Terraforming. Please note that not even the supercomputers at NASA can provide us with a perfect simulation. The information showed here is only an approximation.
Basic data[]
- Distance from Sun: 1453.53 million km
- Distance from Saturn: 1.222 million km
- Diameter: 5151 km
- Solar Constant: 0.0209
- Mass: 0.0225 Earths
- Mean density: 1.880 kg/l
- Saturn's period: 29.457 Earth years
- Day length: 15.945 Earth days
- Rotation axial tilt: 27 degrees
Atmosphere[]
Data varies, depending on what type of atmosphere we want to have. Titan has a low gravity, which makes atmosphere more fluffy then Earth's.
During this simulation, we will use an atmosphere with the same pressure at sea level as Earth's and a similar composition.
- Atmosphere stability for oxygen molecules:
- Earth's gravity (15 degrees C): 4.116
- Titan's gravity (15 degrees C): 17.44
- Titan's gravity (-150 degrees C): 7.45
- Atmosphere stability for water molecules:
- Earth's gravity (15 degrees C): 7.320
- Titan's gravity (15 degrees C): 31.01
- Titan's gravity (-150 degrees C): 13.25
- Atmosphere stability for hydrogen molecules:
- Earth's gravity (15 degrees C): 65.88
- Titan's gravity (15 degrees C): 279.1
- Titan's gravity (-150 degrees C): 119.3
notes: A value below 10 means stability for over a million years, a value between 10 and 100 means stability between 0.1 and 10 millions of years, while a value higher then 100 means stability for less then 10 thousand years.
This calculation does not include solar wind erosion.
Conclusion: The atmosphere of Titan will be separated in two layers: below and above the greenhouse gas buffer. Below, both water and oxygen are metastable. Above, oxygen and nitrogen (which has a similar mass) are stable for millions of years. Water vapors could escape into space, but that process will be very rare, since most of water will freeze and fall back to the surface.
Hydrogen, resulting from interaction between water molecules and ionizing radiation, will escape into space. However, this process will be rare because solar radiation is low at that distance and because Titan is, for most of its orbit, protected by Saturn's magnetosphere.
The atmosphere will look like this:
Ground average temperature: 15 degrees C
- Surface pressure at sea level: 1
- Atmosphere total mass (Earth = 1): 0.69
- Atmosphere breathable height: 90.3 km
- Atmosphere total height: 269 km
Ground average temperature: -150 degrees C
- Surface pressure at sea level: 1
- Atmosphere total mass (Earth = 1): 0.72
- Atmosphere breathable height: 37.0 km
- Atmosphere total height: 110.1 km
Combined values
- Atmosphere total mass (Earth = 1): 0.71
- Atmosphere breathable height: 64 km
- Atmosphere total height: 189 km.
As one can see, Titan maintains its atmosphere because of its low temperature. It is the outer, cold layer, that will hold a terraformed atmosphere into place.
Temperature[]
Main article: Temperature.
The first problem with Titan is that we need to gain the correct surface temperature. The Solar Constant is small (0.0209), compared to Earth (1.98). We will need Greenhouse Gases. The Greenhouse Calculator shows us that Titan will need 0.656 kg/sqm of sulfur hexafluoride.
Climate Simulation[]
Main article: Climate.
On Earth, the average temperature is +15 degrees C. Technicians will try, with the help of greenhouse gases, to keep this temperature.
Titan has a smaller diameter then Earth (0.404), so air currents can mix temperatures faster. The atmosphere will be high enough to pass over most Geographic barriers.
Average temperatures for each latitude:
At equinox:
- poles: 12 C
- 75 deg: 14 C
- 60 deg: 14 C
- 45 deg: 15 C
- 30 deg: 15 C
- 15 deg: 16 C
- equator: 16 C
At winter solstice:
- poles: 11 C
- 75 deg: 11 C
- 60 deg: 13 C
- 45 deg: 14 C
- 30 deg: 14 C
- 15 deg: 15 C
- equator: 15 C
At summer solstice:
- poles: 15 C
- 75 deg: 15 C
- 60 deg: 16 C
- 45 deg: 16 C
- 30 deg: 16 C
- 15 deg: 16 C
- equator: 15 C
Day - night cycle variation:
Titan has a very long day (15.945 Earth days), but is well protected by its greenhouse layer. So, temperature variations between day and night will not be significant.
- Daily temperature variation: 2.5 degrees C
- Equator day-night variations:
- Equinox: 15 to 17 degrees C
- Solstice: 14 to 16 degrees C
- Day - night variations for 45 deg latitude:
- Equinox: 14 to 16 degrees C
- Winter solstice: 13 to 15 degrees C
- Summer solstice: 15 to 17 degrees C
Seasons:
Titan has its axis significantly tilted. This results in some seasons. However, because of the strong greenhouse effect that will be needed, temperature differences will only be of a few degrees. It will be like an endless spring. It will never snow in winter and it will never be too hot in summer.
Altitude variations:
Titan does not show high elevations and deep depressions. Air currents will easily pass over obstacles. Also, because the atmosphere will be fluffy, especially below the greenhouse gas layer, there will not be significant temperature changes with altitude. Snow will probably be found only on mountains rising above 10 km.
Conclusion.
Titan will have interesting climate patterns. It will be a monoclime, as nearly any Outer Planet will have. Still, there will be some seasonal variations and a small day-night temperature change. Protected by its strong greenhouse layer, the atmosphere will offer conditions of an endless spring.
When we combine the climate simulation with atmosphere parameters, the results are even more interesting. Below the greenhouse layer, both oxygen and water vapors are metastable. Above, where temperature is low, both become stable.
Every molecule inside a gas moves with an average speed that is dependent of temperature and its own mass. An atmosphere is unstable when a significant part of its gas molecules reach a speed approaching to the escape velocity. On Titan, this might happen below the greenhouse layer, but not above. Water vapors, which are lighter then oxygen molecules, might tend to migrate above the greenhouse layer, but once they get there, they will freeze and fall back fast, without getting too high.
This process has a significant importance for Titan. With small temperature changes, water accumulates in the atmosphere of an outer planet until the air is saturated with vapors. Without a significant temperature drop, it does not rain strong enough to clear the sky of clouds. On Titan, on the other hand, the fact that not much water will reach the upper atmosphere ensures the sky will be cleaner. Still, it will be foggy, but there will be rare days with a clear sky.
Geography[]
See also: Geography and Geographic Pattern - Erosion.
Before terraforming Titan, settlers must acknowledge its composition. The moon has lakes of carbohydrates and deposits of tholins on its surface. The crust is, however, made of water ice. Beneath it, there is a massive subsurface ocean that is as salt as the Dead Sea and also might contain high deposits of ammonia. A very salt ocean will not be something we want to have. Also, given the very little heat we receive from the Sun, we will need much time to melt the ice. The crust appears to be stable. We seen no volcanic activity on the moon.
Because of all these features, it appears that Ground Insulation is feasible for Titan. The other two methods (building Artificial Continents or transforming it into an Oceanic Planet have the disadvantage that they will expose the ocean, which will not be of any economical value. Also, with high amounts of ammonia dissolved in it, the ocean has another major problem. Ammonia is kept dissolved with the help of great pressure. If we break the crust, we might witness massive outgassing, that will destroy all ecosystems we want to create.
If technicians will prefer the use of ground insulation (with materials that can be made using hydrocarbons from the surface or materials extracted from the subsurface ocean), then we can save the Geographical patterns the moon already has.
Oceans. Based on current altitude map, Titan will not have a single ocean, but at least five. To prevent them for being endorheic, it will be wise to connect them. This will not be hard to do, since altitudes are low. The oceans will be shallow. The moon has enough water in its crust to fill the oceans.
Still, there will be many endorheic basins, mainly around the equator.
Rivers. Close to the poles, the former methane canyons can be transformed into valleys. Around the equator, canals for rivers could be dug. Since it will rarely rain, rivers will be very small. We have to keep an eye on erosion, to avoid destroying the ground insulation.
Continents. Titan will have a global continent that will encircle all oceans.
Mountains. There is a chance that, during terraforming processes, many mountains will be erased to provide water for the oceans. Still, some might remain and others might be created.
The Sky[]
As any Outer Planet, Titan will have a lot of moisture in its atmosphere. Because of this, fogs and clouds will be common. For most of time, no celestial body will be visible on the sky.
Still, assuming the sky will allow settlers to see celestial bodies like we see here on Earth, the sky will be interesting.
The Sun will appear 0.97 units wide (like an object 0.97 mm wide will appear if you look from a distance of 1 m, see Angular Size for details).
Saturn and other satellites visible as disks will be:
- Saturn - 95.3 units
- Mimas - star to 0.38 units
- Enceladus - 0.34 to 0.51 units
- Tethys - 0.70 to 1.15 units
- Dione - 0.70 to 1.33 units
- Rhea - 0.87 to 2.20 units
- Hyperion - star to 1.04 units
- Iapetus - 0.31 to 0.36 units.
Some planets will also be visible:
- Mercury: 4.6 to 4.8
- Venus: 1.7 to 2.0
- Earth: 2.9 to 3.4
- Mars: 5.9 to >6
- Jupiter: -0.2 to 2.4
Because titan has its axis about 0.5 degrees tilted from Saturn, the rings will be visible.
Human Colonies[]
- Population limit: 8.88 million
- Land population feeding capacity: 3.3 people fed from one square km
- Largest city supported by environment: 35 000 people
Assuming it will have similar types of terrain Earth will have, Titan can support a Population Limit of 8.88 million people.
As one can see, climate on Titan will not be quite friendly. The air will have enough moisture to affect health after long-term exposures.
Industry[]
Titan is the best candidate for terraforming in the Saturn System. So, major industrial corporations will avoid Titan, mainly because of concerns related to Pollution.
Still, there are other activities that can be developed, like computer programming and banking, which don't require massive industrial complexes.
Rivers will be small and air currents low. So, the best source of energy appears to be nuclear.
Agriculture[]
There is a lack of light on titan, that will limit plant life (see Plants on new worlds for details). Agriculture is still possible, but large surfaces will need to be planted to feed the population.
Grain crops can live on Titan, but will have very small productions.
Transportation[]
With little gravity, air transport will be efficient. The oceans will not form a global network, so water transport will be limited.
With a global continent, ground transport will be key to titan. A network of roads and railways will be very efficient.
Since Titan is tidal locked, there is no place for geosynchronous satellites. Still, there are many safe orbits around the moon for satellites that will provide telecommunications.
There will be constructed at least one base on the surface, for space travel. Large interplanetary ships, carrying passengers and cargo to and from Saturn, will dock at Helene. Then, smaller ships will ferry between the little moon Helene and Titan.
Tourism[]
If we use ground insulation and we preserve many Geographic landscapes, Titan will be a very interesting place, visited by many tourists from various places.
Wild Life[]
Like all outer planets, Titan offers conditions for plants and animals from wet temperate regions.
Giving the low natural luminosity, Titan is at the limit where forests can grow. However, in a forest, there will be no light left for plants that live on the ground.