Since the end of the Apollo missions that put men on the moon, the people of the United States have had their eyes on what seems like the next logical step: Mars, the Red Planet. Several proposals have been put forward—none of them, obviously, seeing implementation as of yet—and still more movies, TV shows and novels have fantasized about manned missions to Mars.

But, and not to state the obvious, a manned mission to Mars and subsequent colonization presents a whole host of problems. No, I’m not talking about the distance required for travel, even though the multi-month trip has its own challenges. Gravity on Mars is just 38 percent of that on Earth. We already know from experience on the International Space Station that low-gravity environments cause some strange stuff to happen to a human body that’s used to Earth’s gravity. Muscles waste away, bones waste away, blood disappears because our body begins to think we have too much of it. Granted, this is in an environment with almost no gravity, but experiencing even a fraction of those effects would be problematic for daily life.

Mars’ surface temperature is extremely cold, ranging from minus 125 to minus 4 degrees Fahrenheit on a typical day. Though there is evidence of available water on Mars, it’s about as come-and-go throughout the year as the McRib. Mars’ surface pressure is far below the Armstrong limit, the point at which humans begin to boil, requiring constant pressure suits and having every building built like an airplane hull.

High carbon dioxide in the air may seem good for plants, but Mars’ atmosphere has so much carbon dioxide that it would kill any plants exposed to it. On top of it all, the lack of a magnetosphere, which protects us from the space radiation, would cause cancer and radiation poisoning for people living on Mars, even with lead-lined everything.

Mars is a barren Hellscape, but it’s a challenge worth taking because it’s the closest planet to Earth after Venus. Earth, Mars and Venus—orbit the Sun in different ways, meaning the distances between them will vary yearly, but within an ideal window, Venus requires less total propulsion to travel to Earth than a similar mission to Mars. This may be a moot point when you consider the fact that Venus’ surface temperature is so hot that it can melt lead.

Venus is currently shrouded in a thick atmosphere after centuries of runaway greenhouse effect. In other words, Venus has experienced so much climate change that its oceans, if it ever had any, boiled away due to all the heat trapped on the surface. Like a stressed student’s dorm room as a deadline approaches, the sun doesn’t shine there.

But a planet isn’t just its surface. In fact, Venus’ atmosphere is so thick that it can be better thought of as a gaseous ocean. On Earth, balloons filled with helium float in the sky because helium is less dense than air. On Venus, balloons filled with our air would float. With good enough engineering, a large building would float. Venus could hypothetically host floating cities not unlike Cloud City in the Star Wars film “The Empire Strikes Back.”

The outer atmosphere would be quite familiar for a human. NASA scientist Geoffrey A. Landis laid the case out pretty well in “Colonization of Venus,” in which he called the Venusian atmosphere 50 kilometers above the surface the “most earthlike environment in the solar system.” Up there, gravity is 90 percent that of Earth’s (not likely to cause health problems), the temperature varies from about 32 to 122 degrees Fahrenheit and the air pressure is the same as Earth’s. Venus’ atmosphere offers substantial protection from cosmic rays and radiation. One could hypothetically roam the exterior in firefighter’s gear, needing only a breathing apparatus and clothing to provide protection from the acidic atmosphere.

Given the enormous costs of space travel and proposed missions, one might step back and ask “why?” There isn’t a rush to get to another planet like there was a rush to get to the moon during the Space Race. Sure, China and Russia have both put forth mission proposals, but NASA alone has experience sending people to other terrestrial bodies, and American companies like SpaceX may soon expand the United States’ space chops. There’s little political pressure for the government to conduct another manned landing.

Venus presents unique scientific and economic opportunities that we don’t have on Earth. For scientific research, Venus is a lucrative, planet-sized lab for something we’ve seen the devastating effects of this summer: climate change. Unprecedented temperatures, hurricanes and fires have ravaged the North American landscape, and that doesn’t include the effects in other regions of the world like expanding deserts, disappearing oceanic wildlife and blankets of smog in China that make the atmosphere feel less like a bubble and more like an ocean. From Venus’ “oceanic” atmosphere, perhaps we can see where our climate is going and how we could potentially stop it. Landis hasn’t called Venus the “greenhouse planet” and “Earth’s evil twin” for no reason.

Economically, the dreams of asteroid mining could be realized on Venus. As Landis pointed out, Venus is closer to the Asteroid Belt than Mars or Earth. Though we often imagine the Asteroid Belt as a dense field, it’s actually quite sparse. One could set up a base on an asteroid, but it would be far away from any neighbors and farther still from asteroids on the other side of the Sun, should one wish to conduct a mission over there. Since Venus has a fairly rapid orbit, one could use a Venusian colony as a rendezvous point for an asteroid mining company. If the Asteroid Belt were likened to the American coastlines, Venus is Kansas City. And with worries about our Earthly resources running out, it couldn’t come soon enough. Perhaps profits from such an enterprise could offset the enormous cost of settling Venus.

It’s true that NASA has had its sights set on Mars for ages, with a manned mission planned in the 2030s. I’m not saying that we shouldn’t head to Mars, a planet that presents its own advantages and, unlike Venus, has a rock-hard surface to work with. But Venus may be a more immediate and worthwhile goal, and much of the equipment being designed and built for Mars could be pointed to Venus instead. NASA’s Deep Space Transport, a reusable spaceship slated for a manned mission to Mars, is also designed to fly to the moon and Venus. Ship design in our Navy could be easily adapted to Venusian colonies. Space suits designed for Mars work on Venus with more features equipped than a Venusian would need. All of this assumes that NASA would get there first. As I mentioned above, private American enterprise is hot on NASA’s heels, and Venus, with its relative ease of habitation and proximity to lucrative asteroids, may present a better profit margin than anything on Mars.

“Earth is the cradle of humanity,” pioneering space engineer Konstantin Tsiolkovsky once said, “but one cannot live in a cradle forever.” It’s not dire, but for a myriad of reasons, humans need to eventually become a multi-planet species if we want to survive. In the meantime, we need to expand from Earth to seize the initial opportunities beyond, and Venus, not Mars, is the best candidate for our first step.


  1. Venus has had runaway greenhouse warming for many, many millennia, eons perhaps. “Centuries” is underplaying a bit.

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