Should we colonize Venus instead of Mars?

John Henrique Oct 28, 2020

When it comes to colonizing other planets, there is a huge disparity between the attention that Mars and Venus receive, both from space agencies around the world and in popular culture.

However, Venus is more similar to Earth in many ways, and is millions of kilometers closer to us, so shouldn’t we colonize it instead of Mars?

In this article, we will cover some factors that make Venus a good candidate for a future human colony, as well as the reasons why many people are opposed to the idea.

Here’s a quick pros and cons list, before we dig into the details:


  • It is closer to Earth than Mars;
  • Proximity to the Sun (good for solar energy applications);
  • Better defense against solar radiation;
  • Gravity similar to that of Earth;
  • No adverse health effects;
  • Easy to terraform.


  • Pressure and temperature;
  • Settlers would live in floating cities.

What does Venus have to offer?

Right now, we have the US and Chinese governments interested in sending manned missions to Mars. In fact, three American presidents (George Bush, Barack Obama, and Donald Trump) set goals to colonize Mars, and they were followed by the Chinese government in that ambition.

Billionaires, like Elon Musk, are investing a lot of money in their own spaceship, and NASA even started looking for potential settlers.

On the other hand, there are no discussions about manned missions to Venus, which was left out of mankind’s space ambitions. And that is kind of weird, since Venus is a cheaper and easier target to terraform.

Distance from Earth

(Credit: TheFactSite).

Venus is 41 million kilometers closer to Earth than Mars, at a distance of 108.2 million km, while Mars is 149.6 million km away. So, a round trip from Earth to Venus would be 30 to 50 percent faster than it would be to Mars.

Today we are able to reach Mars within 150-300 days, depending on the speed of launch. As a rule, it usually takes about 9 months to reach Mars, whereas it takes 97 days to reach Venus, or about 3 months.

If we think about how much food, fuel, and time this would save, Venus offers us a big advantage, because if we want to colonize another planet, we would have to take most of the necessary resources from here.

On August 8, 1962, NASA launched a probe, Mariner 2, which made the first successful flyby to Venus on December 14, 1962, taking only 110 days.

(Credit: JAXA / ISAS / DARTS / Damia Bouic).

Atmosphere and proximity to the Sun

Venus is also closer to the Sun, giving us four times more solar energy than Mars. In addition, its thick atmosphere would offer humans a much better defense against solar radiation and meteorites than Mars’ protective layer.

Furthermore, Venus’ atmosphere is made mainly of carbon dioxide, which, after being filtered from sulfuric acid, can be used to grow food.

Venus and Earth have similar gravity

The gravity of Mars is only 0.38 times that of Earth’s gravity, which can cause softening of the bones and loss of muscle tissue, similar to what is experienced by astronauts living in a microgravity environment.

In contrast, Venus has a size and mass similar to that of Earth, resulting in a very similar surface gravity (0.904 g). This would probably be enough to prevent the health problems associated with microgravity.

The “Ishtar Terra”, in Venus. It is the size of North America and borders large mountain ranges, including Maxwell Montes, which is the highest spot on the planet, even higher than Mount Everest
The “Ishtar Terra”, in Venus. It is the size of North America and borders large mountain ranges, including Maxwell Montes, which is the highest spot on the planet, even higher than Mount Everest. (Credit: NASA).

The effects of Mars’ gravity on humans are not known, but studies with melatonin are being carried out, as some believe that melatonin may hold the secret to preventing adverse health effects associated with microgravity.

It is worth mentioning that the only thing that we cannot manipulate on a planet (at least for now) is the gravitational force, so it makes sense to choose a planet with Earth-like gravity to colonize.

So why don’t we colonize Venus instead of Mars?

At first, it seems that we have every reason to do so: astronauts would be subject to much less space radiation, we would need to take much less food, it would be much faster to get there, and the overall cost of the mission would be much lower.

Furthermore, Venus has a dense atmosphere, much easier to oxygenate to make it habitable (we can extract oxygen from carbon dioxide) than the thin atmospheric layer of Mars. The Red Planet cannot hold an atmosphere, and that is something that we could hardly change.

Despite all of this, Venus has a big downside: we just can’t land on it.

A planet with a bad reputation

When we think about colonizing a planet, we immediately think about walking on its surface, after all, this is how we live here on Earth.

But that would be impossible on Venus, at least for now.

That’s because the atmosphere of Venus is under an intense greenhouse effect. Its surface resembles what we think of as hell.

While Mars is cold and with an average temperature of -63 degrees Celsius, Venus is a place with a temperature of about 426 degrees Celsius. To give you an idea, this is enough to melt lead.

The surface of Venus photographed by the Soviet probe Venera-13 lander.
The surface of Venus photographed by the Soviet probe Venera-13 lander, in 1982. (Credit: NASA History Division).

But when it comes to atmospheric pressure, neither Venus nor Mars are good candidates for colonization.

Mars has an atmospheric pressure of about 1% compared to that of Earth (which would make water turn into gas immediately, dissipating into space) and Venus has an atmospheric pressure 90 times higher than that of Earth.

Surface of Venus
Surface of Venus. (Credit: NASA).

That would be a good reason to drop the idea of ​​going to Venus, if it weren’t for one thing.

NASA studies have found that the atmosphere 50 kilometers (31 miles) above the surface of Venus would be more suitable for humans, with pressure, density, gravity, and radiation protection similar to the Earth’s surface.

Furthermore, at this altitude, the planet’s temperature would drop to about 75 degrees Celsius, which is just 17 degrees higher than the highest temperature recorded on Earth.

This temperature still seems very high, but we currently have suits worn by firefighters that withstand up to 800 degrees Celsius. So, wearing the right clothes, it would be possible to live in that temperature.

Another, more interesting, idea is thermally insulated environments, with an interior temperature artificially maintained. That way, we wouldn’t need to wear any special clothes.

Taking all this into account, scientists began to think about the possibility of building floating cities in Venus’ atmosphere.

Is our future in the clouds?

NASA's HAVOC Project.
NASA’s HAVOC Project.

As early as 1971, Soviet scientists suggested different approaches, saying that instead of trying to colonize Venus’ hostile surface, humans should try to colonize its atmosphere.

In fact, above the clouds of Venus is the most Earth-like environment in the entire Solar System.

For this reason, an internal NASA study has developed a conceptual mission to Venus, known as HAVOC (High Altitude Venus Operational Concept).

This project created the idea of ​​a floating city with astronaut-manned zeppelins hovering over the planet’s atmosphere.

(Credit: NASA Langley Research Center).

Floating cities are not the only way to colonize Venus, but it is the way to colonize this planet by doing as little damage as possible.

But is this idea viable?

This may sound easy in theory, but in the event of a problem, for example, there would be nowhere to land safely.

Besides, with a gravity almost equal to that of Earth, it would be very difficult to return to the planet’s orbit. Each floating city would need propelling capabilities and a lot of fuel at its disposal to return to orbit.

And they would also need to be made of a material strong enough to withstand extremely high pressure and temperature, otherwise, the settlers would simply be crushed.

In contrast, Mars’ lower gravity means that it would be easier to abort a mission if anything goes wrong. And if you miss the landing site, you will still land on a surface, not in a hellish abyss.

Tell us what you think. Considering all the pros and cons, do you think we should colonize Venus instead of Mars?

Today’s recommended books

Related topics:


Written by John Henrique

John has a degree in IT and is the founder of Hyperaxion. He is a science enthusiast and can usually be found reading a book or playing role-playing games.


Leave a Reply

Notify of