Io Simulation

This is a simulation of what one would expect to find on a terraformed Io, 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: 778.57 million km
Distance to Jupiter: 0.422 million km
Diameter: 3643 km
Solar Constant: 0.073
Mass: 0.015 Earths
Mean density: 3.528 kg/l
Orbital period: 1.769 Earth days
Jupiter's orbital period: 11.862 Earth years
Rotation axial tilt: below 10 degrees

Atmosphere[]

See Atmosphere Parameters

Io is very close to Jupiter and has a low gravity. Because of this, it has a very small Hill sphere. The atmosphere after terraforming, if it will have a surface pressure of 1 bar, will be extremely fluffy.

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
- Io's gravity (15 degrees C): 17.97
- Io's gravity (-100 degrees C): 10.80
Atmosphere stability for water molecules:
- Earth's gravity (15 degrees C): 7.320
- Io's gravity (15 degrees C): 31.94
- Io's gravity (-100 degrees C): 19.19
Atmosphere stability for hydrogen molecules:
- Earth's gravity (15 degrees C): 65.88
- Io's gravity (15 degrees C): 247.5
- Io's gravity (-100 degrees C): 172.7

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: Below the greenhouse layer, Io will hardly hold gasses (oxygen or nitrogen). Water vapors will be highly volatile. However, above the greenhouse layer, the atmosphere will offer more stability for gasses. Still, water vapors will have a higher chance to escape into space. We can conclude that atmosphere pressure will not decreases significantly with altitude below the greenhouse layer.

Clouds of water ice will accumulate above the greenhouse layer, partially blocking the light and creating a secondary greenhouse effect.

UV radiation will release hydrogen atoms which will fast escape into space. However, since Io is protected by Jupiter's magnetosphere and solar radiation is weak at this distance, the effect will not be so powerful.

The atmosphere will look like this:

Ground average temperature: 15 degrees C

Surface pressure at sea level: 1
Atmosphere total mass (Earth = 1): 0.68
Atmosphere breathable height: 68.7 km
Atmosphere total height: 200 km

Ground average temperature: -100 degrees C

Surface pressure at sea level: 1
Atmosphere total mass (Earth = 1): 0.53
Atmosphere breathable height: 53.0 km
Atmosphere total height: 157 km

Combined: Atmosphere total mass (Earth = 1): 0.62 Atmosphere breathable height: 63 km

Atmosphere total height: 165 km.

Basically, there will be two different atmospheric layers: below and above the greenhouse gasses. The lower layer will be hotter and will contain most of the air, while the upper layer will be cold and will compress the lower layer.

Temperature[]

Main article: Temperature.

The first problem with Io is that we need to gain the correct surface temperature. The Solar Constant is low (0.073), compared to Earth (1.98). Greenhouse Gases are needed. The Greenhouse Calculator provides us with some useful values. The needed amount of sulfur hexafluoride is 0.189 kg/sqm.

Climate Simulation[]

Main article: Climate.

On Earth, the average temperature is +15 degrees C. By using greenhouse gasses we will try the best to get a similar value.

Io has a smaller diameter then Earth (0.286), a thing that will help air currents mix temperatures. The extremely fluffy atmosphere also helps us maintain a global temperature similar for the whole moon.

Average temperatures for each latitude:

poles: 13 C
75 deg: 14 C
60 deg: 15 C
45 deg: 15 C
30 deg: 16 C
15 deg: 16 C
equator: 16 C

Day - night cycle variation:

Io has a short day (1.769 Earth days). Because of this and the huge greenhouse effect needed, there will be very little differences in temperature.

Daily temperature variation: 1.4 degrees C
Equator day-night variations: 15 to 17 degrees C
Near pole day-night variations: 12 to 14 degrees C.

Altitude:

Because of the fluffy atmosphere, temperature will not decrease significantly with altitude. On the highest mountains, there might be only one or two degrees colder then at sea level.

Seasons:

Io has a very small axial tilt, so there will be no seasons.

Conclusion. Io will behave like a tiny outer planet, protected by a huge greenhouse effect. Lowest and highest temperatures will be 12 and 17 C. There will be a monoclimate.

Water will accumulate in the atmosphere and humidity will tend to be close to 100%. When it will rain, it will be with rare droplets of water.

Geography[]

Io usually has large plains with altitude variations that rise up to 2 km. There are also high volcanoes that rise over 8 km, as well as some deeper depressions. Still, 90% of the ground is not above or below the 2 km average height or depth.

Unfortunatelly, we don't have a complete altitude map of the moon.

Oceans. Assuming that 50% of the surface will be covered with oceans, there is a high chance they will have a complex form, with many islands and many endorheic basins. It is unknown if there will be a global ocean or a global continent.

Endorheic lakes will live more, because there will be little water that will evaporate. The inflow from rainfall will also be little.

Being so close to Jupiter, the oceans will experience massive tides. If we will have a global ocean, then tides should be perhaps 1 km high!

Continents. Assuming 50% will be dryland, there will be lots of islands and peninsulas, forming a complex maze. We don't know if there will be a global continent or there will be many.

Rivers. Rains will bring little water, but there will not be significant evaporation. Rivers will form. Because of the little gravity, rivers will flow very slowly and will erode their valleys even slower.

Volcanoes[]

Io has large, massive volcanoes, that rise very high above the surface. They will be the greatest thread to the ecosystem. With an atmosphere, volcanic ash and lava will not fly so far and will fall faster to the ground. They will dramatically disturb the greenhouse gas layer. If this will happen, we can see holes that will allow heat to escape into cosmos. The moon will cool fast and it will even snow. Over some time, temperature will increase back.

On the other hand, volcanoes will contribute to the atmosphere with carbon and sulfur dioxide, which will alter the greenhouse effect. With this simulation, we cannot estimate for how long will the climate be stable.

A second problem is that volcanic eruptions on the scale seen on Io certainly will trigger massive quakes.

Jupiter has a dense magnetosphere that is being fed with sulfur from Io's volcanoes. When an atmosphere will be put in place, most of this sulfur will not make it into space. The magnetosphere will no longer be as dangerous as it is today. The main disadvantage is that nearly all the sulfur will remain on the moon.

There is a high possibility that sulfur would burn in an oxygen-rich atmosphere. This would create a massive amount of sulfur dioxide.

The Sky[]

As one can see above, the atmosphere of Io will be very fluffy. Clouds and hazes will block visibility. It is possible that settlers will see blue sky only on rare occasions.

Still, assuming sky visibility similar to Earth, one will see the following celestial bodies:

The Sun - 1.79 units
Jupiter - 332 units
Amalthea - 0.33 to 0.83 units
Europa - 2.86 to 12.52 units
Ganymede - 3.26 to 8.12 units
Calisto - 2.09 to 3.30 units

To see how large a celestial body will look like, draw a circle of X mm on a sheet of paper and look at it from a distance of 1 m.

Mercury: 3.2 to 3.6 magnitude
Venus: 0.2 to 0.8 magnitude
Earth: 1.3 to 2.2 magnitude
- Moon: 5.2 to >6 magnitude
Mars: 4.2 to 5.5 magnitude
Saturn: 1.2 to 3.8 magnitude

Human Colonies[]

Population limit: 15.2 million
Land population feeding capacity: 11 people fed from one square km
Largest city supported by environment: 60 000 people

Assuming it will have similar types of terrain Earth will have, Io can support a Population Limit of 15.2 million people.

As one can see, climate will be very wet, not good for health for a long time exposure. This is common for mostly all outer planets.

Industry[]

In the outer Solar System, there are only rare celestial bodies with a low concentration of water. Io is one of them. This moon has active volcanoes and rivers of sulfur, which bring important materials for industry on the surface. Io might become Jupiter's center of metallurgy and chemical industry.

On the other hand, this moon experiences powerful natural disasters and has a very high risk of quakes. So, many industrial corporations will prefer only to mine and refine ores here, sending refined materials to the other moons.

The major question is if Io will be or not terraformed. If the moon will be terraformed, it will need a lot of maintenance or might end-up as a Short Lived Earth.

If Io will not be terraformed or if a major volcanic explosion will destroy its climate beyond recovery, then Industrial colonization will take place on a large scale. In such conditions, industrial development will bring Pollution to the moon.

Probably the most accessible source of energy will be geothermal. Also, Io might contain enough radioactive ores (uranium and thorium) that can be used by nuclear plants throughout the Jovian system. With a massive risk of quakes and volcanic eruptions, nuclear plants on the surface of Io might get destroyed.

Agriculture[]

With little light received from the Sun, Io will produce little food for settlers. There is also a high risk that its ecosystem will be blown away by a volcanic explosion.

Transportation[]

With little gravity and a large atmosphere, the best way to move things around will be by air. The oceans will experience massive tides and will be not a good option. Ground transportation might be a solution, at least for small distances. Volcanic explosions will produce quakes and cracks, destroying any infrastructure.

The orbits around Io are not safe. Satellites will be affected by gravitational perturbations from Jupiter and other moons. If they are too close, atmospheric drag will slow them. Also, Jupiter's magnetosphere will affect most equipment.

For telecommunications, it might be possible to use relay stations orbiting other moons or Jupiter. Also, a few satellites can orbit for a limited time Io.

On the surface, there will be one or more bases. A base cannot grow too large because it will be destroyed by quakes.

Interplanetary traffic will be shipped to Himalia. From there, smaller ships will transport cargo and passengers to and from Io.

Tourism[]

Io will be popular for its volcanoes and its close sight of Jupiter.

Wild Life[]

Io will have a monoclime, with high moisture and average temperatures of 15 C. In such conditions many plants and animals from wetlands can live.

Io can be a good place for saving endangered Earth species that live in swamps and other wetlands.