Colonization of Venus

The colonization of the planet Venus, the nearest planetary neighbors of the earth, has been frequently discussed in the past. After the discovery and exploration of the hostile surface conditions, the discussion centered colonies beyond Earth has mainly shifted to the moon and Mars. More recently, however, several papers were published that has picked up the issue again. Add new approaches colonization is to be transferred among others in the cloud cover of the planet.

• 2.1 Floating Cities
• 2.2 colonies in orbit

Arguments for and against Venus colonization

Benefits and reasons

Venus has many similarities with the Earth, which could facilitate the comparison with other celestial bodies, a colonization. It is because of these similarities, also known as the " sister planet " Earth.

• Venus is of all the planets of the solar system the Earth in mass and size most similar. Its surface gravity is 0.904 g and is thus comparable with the earth. In a Venus colonization so that the adverse health effects by gravity or low gravity could be avoided.
• The upper atmosphere of Venus is at an altitude of about 50 kilometers in terms of temperature and air pressure similar to (1 bar, at 0-50 degrees Celsius). It can also be obtained from this height sufficient solar energy, since on every square meter of about 2610 watts of sunlight falls to 1.9 times the amount of solar radiation the earth. The clouds reflect a large part of it, so you could set up solar panels to the sun as well as to the planet's surface to generate electricity.
• Furthermore, rotate the upper regions of the atmosphere in 100 hours or less around the planet, which would allow for a nearly day and night rhythm (as opposed to the surface, which requires 243 Earth days to orbit )
• Apart from the Moon, Venus is the closest celestial body to the Earth, which would simplify communication with the colony and transportation. Current spaceship drives assuming all 584 days opens a launch window between Earth and Venus, compared to 780 days for Earth - Mars. The slightest approach Earth and Venus at a distance of 45 million miles, Earth and Mars have 56 million km.

Rebuttal Argument

• The surface conditions of Venus are extremely hostile to life. Due to the greenhouse effect, the temperatures are about 500 degrees Celsius near the equator, enough to melt lead. The atmospheric pressure at ground level is at 90 bar, equivalent to the pressure in a kilometers of water depth. These conditions meant that the space probes Venera 5 and Venera 6 already 18 and 10 km were crushed on the floor. Venera 7 and 8, which follow them, reaching the surface, however, both survived less than one hour. It follows that a transport of materials would be difficult to make from the surface, for example, from raw materials.
• Water almost completely absent on the planet. The atmosphere has no molecular oxygen, but consists of toxic levels of carbon dioxide and clouds of sulfuric acid and sulfur dioxide fumes.
• The biggest problem seems to be the extremely slow rotation of Venus. A solar day is 117 Earth days long on Venus. In a thinned atmosphere after terraforming the dayside would become very hot and cool the night side strong. Large amounts of water would evaporate on the day side and the clouds were being driven by giant hurricanes on the night side and rain down there. The necessary rotational acceleration would require enormous energy needs.

Methods of colonization

Given the hostile conditions on Venus is not possible colonization of the planet with current technological means. Therefore, it is usually suggested that the first means of terraforming Venus habitable (s) to make. The necessary amounts of energy are enormous, and would see results, it can take thousands of years. However, there are approaches that could be realized in the near future, two approaches are shown below.

Floating cities

Geoffrey A. Landis suggested to circumvent the difficulties of the surface by the colonies, similar to hot air balloons or airships could float in the atmosphere. Starting point here is that the air mixture that we breathe (78 % nitrogen, 21 % oxygen) lighter than the atmosphere of Venus. Breathing air would there about half the lift as helium in the Earth's atmosphere. Alternatively, could filled with helium or hydrogen, which could be obtained from the environment, provide additional buoyancy additional balloons.

Colonies in orbit

Another promising approach is the use of Venus to keep comets and asteroids in orbit. Although the Venus currently has no moons, the orbits of smaller bodies can be manipulated so that they are captured by the gravity of the planet. Why Venus is so good for it because it causes a high atmospheric braking. It is better than the earth for such projects, since an erroneous course and the impact of the body on the planet would be safe for humans. The freely available solar energy in the vicinity of Venus could promote future industrial development.

Terraforming of Venus

This section describes the different proposals to make Venus habitable for humans. For information about the process and the requirements of terraforming in general, see terraforming.

Carl Sagan suggested in 1961 to intersperse algae in the atmosphere, and thus to gain from the existing carbon dioxide oxygen. However, we now know that the presence of water on the planet are so low that photosynthesis would win only negligible amounts of oxygen.

Following the study by Paul Birch from the 1991 Robert Zubrin suggested a solar shield, which, simply stated, casts a shadow and the planet cools thereby to bias the Venus to them first to 304.18 K and atmospheric pressure from 73.8 bar to cool ( the critical point of carbon dioxide ), and then continue to 216.85 K and 5.185 bar ( the triple point of carbon dioxide). From this point resublimated the CO2 and settles as dry ice on the surface down. This dry ice would then either disposed of or transported to Mars ( there to speed up the terraforming ) So the problems of heat, the greenhouse effect and the air pressure would be solved, but also Zubrin has to admit that the lack of water remains a serious problem that could not be satisfactorily resolved itself by bombardment of comets. Birch proposes to take a Saturn moons from orbit and bombard the Venus with its fragments, which would lead to an amount of 100 liters of water per square meter.

Landis also proposed to combine the colonization by floating cities and the construction of a solar shield, so that a direct colonization would go in the near future and the terraforming of Venus later hand in hand. These solar shields could even consist of carbon nanotubes, whose raw material carbon could be obtained directly from the air.