Is It Smarter to Colonize Venus Before Mars?
Why Venus may be the better option for long-term colonization
There’s been a buzz of excitement in recent years about the potential colonization of Mars, significantly sparked by NASA’s Artemis missions and SpaceX’s continued testing and development of Starship. For most people, it’s fair to say that the first planet thought of for colonization is the red, dust-covered, freezing planet we call Mars. However, since the 1970’s scientists have been brainstorming colonization techniques for Earth’s sister planet, Venus. So, could Venus be a better option for colonization than Mars?
Pros
There are many advantages for choosing to colonize Venus over Mars, here are a few of them:
Proximity to Earth
At its farthest distance from Earth, Venus is about 87 million miles closer to Earth than Mars, meaning the time it takes to get to Venus could be 30–50% shorter than the time it takes to get to Mars. In turn, this could lead to Venus being more economically practical and would expose astronauts to effects that are harmful to the human body such as microgravity and radiation for a shorter period of time.
Proximity to the Sun
On average, Venus is a bit more than twice as close to the Sun as Mars, resulting in solar panels providing significantly more power if located on Venus.
Thicker Atmosphere
Because Venus has a thicker atmosphere than Mars, it can better protect humans from threats like radiation and meteorites coming into contact with the surface of the planet. Additionally, Venus has an immense buildup of carbon dioxide inside its atmosphere, which in the future may be a resource we can use to extract oxygen from.
Gravity
As a more massive planet, Venus naturally has more gravity than Mars. In fact, the gravitational force of Venus is about 0.9 times that of Earth, while the gravitational force of Mars is about 0.4 times that of Earth. The significant decrease in gravity means that until we find a solution, humans cannot stay on Mars for very long without serious consequences to their physical health, and must exercise for at least an hour everyday so as to help prevent severe bone and muscle loss.
Cons
While there are good reasons to begin colonizing Venus instead of Mars, there are plenty of drawbacks as well, and here are some of them:
Immense Pressure
All that carbon dioxide trapped inside Venus’ atmosphere is creating extreme greenhouse effects, heating up the surface temperature to over 450 degrees Fahrenheit (232 degrees Celsius). Additionally, the pressure is so intense that even military-grade submarines could only last on the Venusian surface for an hour or two, seeing as how they can’t withstand much more than about 75 times the pressure of surface level on Earth, but on the surface of Venus there’s almost 90 times the surface pressure of Earth.
This is one of the reasons why many of the early probe missions to Venus were failures, and even now our best reinforced probes only get a few hours of life before being crushed by the overwhelming pressure.
Acid Rain
Caused by the reaction of sulphur dioxide and water in the atmosphere, the rain on Venus is highly acidic, about two or three times more harmful than the worst acid rain on Earth.
Gusting Wind
To say the winds on Venus are powerful is quite a large understatement. Winds on Venus can reach speeds of up to 220 mph (360 kph), which is about 60 times faster than the planet’s rotational speed. On Earth, even the fastest winds never exceed speeds of more than 10–20% of Earth’s rotational speed.
Day-Night Cycle
Oddly enough, due to a slow axial rotation one whole day on Venus lasts about 116 days and 18 hours on Earth. This means that any Venusian colonists will spend a long time with full sunlight followed by a long time with full darkness outside. This is not as big a deal as the others, but it can still negatively affect astronauts.
If the Surface Is Extremely Hostile, How Do We Colonize Venus?
The short answer is really quite simple, we don’t settle on the surface. Instead, we make our home above the clouds. About 30 miles (50 kilometers) above the Venusian surface is an environment about as similar to the Earth as we’ll likely find in the entire solar system. It has similar levels of pressure, gravity, radiation, and the temperature isn’t too far off either, usually around 80–120 degrees Fahrenheit (about 30–50 degrees Celsius).
Floating Cities
Similar to something out of a sci-fi movie, a sort of floating establishment would probably be our best method of colonizing the sky of Venus. If there was enough Earth air in an object with slim exterior barriers, then it could float in the sky of Venus much like how blimps float in the air here on Earth. This is because the atmosphere of Venus is full of dense carbon dioxide, so breathable air from Earth containing oxygen and nitrogen acts like helium does in the Earth’s atmosphere, just not quite as powerful of a lifting force.
NASA have already assigned a team of engineers to brainstorm the concept, called Project HAVOC (High Altitude Venus Operational Concept). For powering the cloud cities, the obvious choice would be solar panels. They can be attached to the roofs of airships and seeing as how they’ll be above the clouds there should be plenty of solar energy to harvest.
In the future, if there are well established floating cities above the clouds on Venus, humans wouldn’t actually need any fancy spacesuit to go outside. Of course, they would still need a constant supply of oxygen and protection from possible acid rain, but that’s pretty much all the challenges we would face while going outside. We wouldn’t have to use any bulky pressurized suits because the pressure would be almost identical to that of Earth.
Are There Any Future Terraforming Possibilities?
To make Venus more hospitable for human life, the two main objectives are to cool the temperature and reduce the pressure on the surface. If these are taken care of then Venus will be almost as hospitable for humans as Earth.
Cooling the Temperature
To turn Venus from a melting pot to a more Earth-like environment, reducing the temperature is key. There aren’t too many good ways to go about this, but scientists have theorized that setting up a massive amount of objects in space known as solar reflectors could work. Essentially a ginormous mirror, they work by deflecting sunlight that’s about to reach Venus and sending it on a different path, avoiding the planet and thereby slowly cooling it. In addition, it may be possible to build cooling pipes underneath the ground to cool the surface temperature.
Reducing the Pressure
The second key component of making the Venusian surface a habitable place for human colonization is to reduce the surface pressure, which is equivalent to about 90 of Earth’s atmospheres. Scientists have proposed the idea of bombarding the surface of Venus with mass amounts of Hydrogen bombs. When the bombs react with the plentiful amount of carbon dioxide in the air, they’ll create water and graphite, eventually covering 80% of the planet in shallow oceans.
Unfortunately, this is likely to take a long time seeing as how to get enough Hydrogen we would have to harvest lots from Jupiter or Saturn, in addition to acquiring Iron Aerosol from astroids. Needless to say, a task like this would require significant technological innovations and even then would still take years, and most likely decades to complete. Once finished, the pressure will be only 3 times that of Earth, and from there it may be possible to use devices to extract carbon dioxide from the atmosphere to produce oxygen, reducing the pressure that little bit more to make Venus feel just like the home we know on Earth.
Conclusion
Compared to Mars, Venus may be closer in size and gravity to Earth, and its thicker atmosphere may give astronauts more protection from harmful radiation, but it’s hard to say we should colonize Venus before Mars. For starters, the technology needed to colonize the atmosphere of Venus, much less the surface itself, is incredibly complex. Whereas, for Mars it would still be complicated, just similar to what we’ve been through before. Landing humans on the Moon isn’t too different from landing them on Mars, and our probes and rovers sent to Mars have a higher success rate and have gathered more information than the ones sent to Venus.
In summary, for the short-term Mars may be the better option for human colonization in the solar system due to it being cheaper and more accessible with current technology. However, lack of natural protection against radiation and low gravity on the red planet make it difficult to imagine humans living there for more than a few years at a time, not quite sustainable for long-term habitation.
For the long-term, Venus is almost certainly better than Mars because humans won’t have to worry about bone loss or radiation, enabling them to stay on the planet for longer periods of time. It’s very possible that before the century is up we’ll have built self-sustaining cities in the sky or even on the terraformed surface of Venus, and it will truly be the sister planet to Earth.
