Floating City on Venus

Introduction

Venus is the second planet in a row among the eight planets in our solar system that orbits the sun. It is named after the Greek goddess of beauty and love. Venus is the second closest planet to the sun after Mercury and it is the closest planet to the earth. That’s why Venus is visible from the earth with our naked eye. Venus is the largest terrestrial planet with mountains and active volcanoes. Venus has a similar mass to that of the earth; therefore it has 90% of earth’s gravity. Due to the dense atmosphere of carbon dioxide and thick clouds of sulphuric acid rotating at a high speed, Venus’s rotational speed is incredibly slow; ie 6.5 km/h compared to our earth's rotational speed of 1610 km/h. Venus completes one rotation in 243 earth days. Venus takes 225 earth days to complete one revolution around our sun. Therefore a year on Venus is shorter than a day on Venus. Venus has an axial tilt of 177 degrees concerning the planetary plane of rotation. Therefore it appears to spin backward. Venus is the only planet to rotate clockwise contradicting the counter-clockwise spin of other planets. So, on Venus sun sets in the east and rises in the west

Venusian missions and exploration

Due to its near elliptical orbit, Venus would come closer to earth than any other planet by 47.2 million miles for a significant period. Therefore a Venus exploration would be economical compared to mars exploration. Soviet Union’s Venera series spacecraft made its first successful landing on Venus.it survived against the harsh Venusian atmosphere for twp hours. NASA’s Magellan orbiters used radars to peep through the dense clouds to study its surface. At present, Japan’s Akatsuki orbiter is orbiting Venus and studying its surface and atmosphere.

Venusian surface and atmosphere

Venus has 90% of earth’s gravity and the surface pressure would be 92 times greater than that of earth. Its surface comprises of high mountains and active volcanoes and thousands of craters. The atmosphere here consists of 96% carbon dioxide and 3.5% nitrogen. Traces of sulfur oxides, hydrogen disulfide, carbonyl sulfide are also present which indicates that frequent volcanic eruptions take place. The troposphere extends from surface to 50km from the surface but 90% of the atmosphere is located from surface to 28km. due to the extreme temperature on the surface, carbon dioxide would be in the form of the supercritical fluid. dense clouds of sulphuric acid cover the upper portion of the atmosphere. At a distance of 50 km from the surface, the temperature and pressure are similar to that of earth. This is a positive indication regarding the colonization of Venus.

Colonization of Venus

We are fantasizing about colonizing the moon and mars and many explorations and missions are being planned by NASA to colonize the moon and later planning for first manned missions onto mars. Venus which is 47.2 million km away from earth is closest to the earth than mars which are 167.5 million km away. As far as commutation is concerned, reaching Venus would be easier, faster, and economical than reaching mars. But the harsh atmosphere limits our hope of survival over there. But research is going on to occupy the area 55 km from the surface where the temperature and pressure are (75 degrees maximum, 21 degrees minimum) and 1 atm respectively. Some scientists plan to construct a huge mountain-like structure from surface to 55 km above using robotic bulldozers and machinery and build a colony over there. But the dense atmosphere and huge clouds of sulphuric acid make the work tedious. So for me, the idea of the development of floating cities seems adaptable and feasible.

Floating City

In this theoretical concept, huge bi-layered balloons of helium and breathable air filled with nitrogen and oxygen respectively are made lighter than air materials with the strength and durability like carbon nanotubes. Then a colony which sustains and supports human life is constructed over the top of this balloon like structures. This structure has to be placed inside a sealed air shell and heatshield while taking off from the earth's atmosphere and entering into the Venusian atmosphere. After reaching the destined point, the air shell is ejected out and the structure is placed onto the Venusian atmosphere 55 km from the surface. As the atmosphere is dominated by carbon dioxide, the gases inside the balloons like helium, nitrogen, and oxygen which are lighter than carbon dioxide, acts as the floatation and propelling device. In our floating city, there is no need for a pressurized space suit as the pressure is similar to that of earth. As the temperature over there would be 75 degrees which are slightly higher than the highest temperature on earth and the air would be filled with unbreathable CO2, a normal suit is enough to overcome this problem. As the gravity over here is 90% of the earth, astronauts won't be facing the problem of bone demineralization and reduction in muscle stiffness. The elements like chlorine, sulfur, hydrogen which is essential for sustaining life is present over here. The clouds over the dense atmosphere move at a speed of 340km/hr and can complete one rotation over the Venus in 5 days. Therefore, the floating city can take the energy from the winds to rotate around the Venus, and the day and night cycle can be adjusted. Even energy can be harvested by the extraction of power from wind.

Challenges Involved

One of the major challenges is to lift off from the earth's surface and land onto the Venusian atmosphere without touching the surface. The air shell concept solves most of the problem; still we cannot determine the success rate of this technique. Secondly, the floating city has to survive from the corrosion attack of sulphuric acid. We have to coat the city with anti-corrosive paints to overcome this problem. Next is the production of oxygen. As we know that the atmosphere is mainly filled with CO2, we can use artificial photosynthesis to convert carbon dioxide into oxygen by zapping it with powerful lasers. But still the success rate of this process is ambiguity.

Conclusion

Even though colonizing Venus is a tedious task compared to mars, it has many positive aspects mentioned above. I have not delved into the details regarding the construction of the floating city as it becomes too long for an article. Scientists are working over this floating city concept and many more concepts and together let's hope that one day we can colonize our sister planet, Venus.