The Ishtar, Floating Venusian Habitat

Why Venus?

Venus is widely regarded as something like a polar opposite to Mars, the arguably more popular destination for a future manned mission. However, before Earth’s obsession with Mars, Venus was widely regarded as the favorite. It’s closer in size to Earth, it features an atmosphere that harbors clouds, has far lower radiation than Mars and it has signs of once bearing liquid water oceans. In modern times, several short lived scientific probes have reduced interest in Venus. It was soon realized that the surface is hot enough to melt lead and the clouds are actually sulfuric gas. It’s no surprise why destinations such as Mars and Europa appear to be far more inviting compared to the lead-melting hell hole that is Venus. That said, if Mars one day gets its own manned mission, who’s to say Venus isn’t next? The potential of an atmosphere and relatively safe radiation are too great to pass up.

The surface of Venus is inhospitable, there’s simply no way around it. However, at an altitude between 50 and 70 kilometers exists something of a temperate zone. The temperature, UV radiation and pressure here are shockingly comparable to Earth.

For the sake of this project, I’ve decided to go with a location in the northern Ishtar Terra region. This would likely be a temperate zone where the base could get a stable day/night cycle. Being so far north would also keep the temperature somewhat cooler which would save the air conditioning units from becoming overworked.

The “Ishtar” base consists of five primary habitats, each equipped with some basic necessities for survival on Venus. In order to survive, each part of the habitat must be capable of the following:

• Resisting sulfuric acid
• Staying afloat above the dense superheated clouds
• Reflecting heat/keeping inhabitants cool
• Producing breathable air
• Maintaining a safe, pressurized environment

Some materials resistant to sulfuric acid conveniently include nickel alloys which can be very light which is excellent for interplanetary travel. In this case, I have gone with a mix of stainless steel and nickel aluminide to construct every external structure. (although in the model I used glass to keep things visible)

For staying afloat, hydrogen (or ideally helium 3) bladders will be used. Assuming the entire base weighs only as much as 3 times the space station and the pressure at the altitude Ishtar rests at is 1 bar (for convenience) then the volume of gas needed is as follows: 

• 1,000 cubic feet of hydrogen = 60 pounds of lift or .06 pounds per ft^3
• 1 space station = 925,000 pounds
• 925,000lbs / .06 lbs/ft^3 = 1.5417x10^7 ft^3 which can be made optimally by a roughly 250 ft cube of gas
• The whole model is scaled to 1:12 and supported by three cubes of gas

Each habitat contains an air scrubbing unit, capable of maintaining 1 atmosphere of pressure within the Ishtar. These units also maintain a safe temperature on top of circulating oxygen from the greenhouse for Venusians. 

The base consists of 4 separate habitats, each equipped with their own unique functions. To the left is the habitation module. This module contains room for sleeping and fitness to keep astronauts healthy. The gravity on Venus is only 8.87 m/s^2 on the surface which is slightly less than that of Earth and will be further reduced by the altitude of the base. However, it is still substantial enough to maintain adequate bone density.

The habitat on the right is the medical station and greenhouse. Here food can be grown on the layered grow beds. Plants, such as potatoes and carrots, are good candidates for growth on other planets as they are relatively easy to produce and provide considerable crop yields. The medical floor of the base will contain mostly medical storage for emergencies but it will also have operating tables, dental chairs and medical laboratory equipment. Whatever necessary medical supplies are needed could be brought to the Ishtar due to the ample room on this floor.

The rear central habitat houses the cafeteria/kitchen and scientific hub. Here is where astronauts will be able to converse, spend leisure time and enjoy meals. Upstairs is where research is to be conducted and data can be stored.

The final central hub is where power and communications are managed onboard. Generating power is often an issue in the cold ruthless environment of space which renders few options beyond solar obsolete. However, the excessive heat present just below the cloud layers present an excellent opportunity to utilize thermal energy as a source of continuous power. Communications can also be sent and received from this module as well as access to the airlock is only possible through this segment.

Obviously The Ishtar is far from becoming a reality, especially considering how much more is known about Mars. However, were a manned mission to take place on Venus a floating habitat would solve many of the current issues with surviving the planet. Many of the components used are made of nickel alloys to resist sulfuric spray and could even be used to protect the hydrogen bladders. The bladders could be made of any malleable plastic material capable of stretching up to the needed volume. The biggest issue with this base is probably getting it there but, due to Venus’ atmosphere, parachutes are actually quite effective. Once released, the gas bladders will also keep all transported goods at the necessary altitude. The platform of The Ishtar is also composed of a foldable carbon fiber which is considered resistant to sulfuric acid and provides a base for expansion and outdoor storage.

In the not too distant future, it may be in humanity’s best interest to colonize not only Mars or the Moon but Venus as well. It has an atmosphere, relatively safe UV radiation and even signs of harboring liquid water at one point. Early missions simply cannot just tolerate the heat present and staying afloat above the clouds not only solves the issue of temperature, but pressure as well. Should a manned mission to Venus occur, staying afloat like The Ishtar is one potential solution that I believe to be not too unrealistic.

Overall I had a great time doing research on this. I was inspired by watching a video about Russia’s Venera probes and my interest was piqued when I learned about the temperate zone in the upper atmosphere. Upon further research, I discovered that the pressure at this altitude is comparable to Earth and relatively protected from the sulfuric clouds. I’m content with how my idea has turned out and I hope you at least found the concept of The Ishtar entertaining. Thank you for reading! Above is just a partial 3D print of the base, before it failed on me lol.

Signing off,

ABartousky (Aiden Perpelitt)