This Is An Image Of Venus Taken In 1974 By NASA’s Mariner 10 Space Probe. The Planet Is Blanketed By

NASA considering cloud cities and air ships for manned mission to Venus

Cloud cities. On Venus. No, this is not the pitch for a potentially awesome science fiction story — this is a real-life proposal currently being considered by NASA. 

Though Venus’s surface is far too volatile for us to visit anytime soon, scientists believe there’s a “sweet spot” in the Venusian atmosphere that would be the perfect place to fly some exploratory air ships and eventually establish a legit cloud city. Even better? They think it could be a whole lot easier than going to Mars. Well, kinda.

At approximately 31 miles above the planet’s surface, you’ll find one atmosphere of pressure and gravity just a tad lower than that of Earth. The average temperature, though admittedly hot, is just 17 degrees (Celsius) above the average Earth temperature. Hot, sure, but not unmanageable. Compare that to the wasteland of Mars, and it doesn’t sound too bad. Plus, since Venus is closer to the sun than Earth, that height is the perfect spot to tap into solar power — which could keep the ships (and cities?) running forever.

The Space Mission Analysis Branch of NASA’s Systems Analysis and Concepts Directorate at Langley Research Center is working on a proposal to send a robotic probe followed by manned air ships to the planet, leading to a permanent settlement. The five phases would include robotic exploration, a crewed mission to orbit on a 30-day mission, a crewed mission to the atmosphere on a 30-day mission, a crewed mission to the atmosphere for one year and finally a permanent human presence.

So, why might this be easier (in some ways) than a mission to Mars? The distance involved. A round-trip jaunt to Venus (440 days) would take almost half the travel time as a mission to Mars (650-900 days). But that doesn’t mean every aspect is easier. As IEEE Spectrum’s Evan Ackerman noted in a report that quotes NASA scientist Dale Arney, putting all the pieces together in motion above an alien planet wouldn’t be for the faint of heart:

The crewed mission would involve a Venus orbit rendezvous, where the airship itself (folded up inside a spacecraft) would be sent to Venus ahead of time. Humans would follow in a transit vehicle (based on NASA’s Deep Space Habitat), linking up with the airship in Venus orbit.

Since there’s no surface to land on, the “landing” would be extreme, to say the least. “Traditionally, say if you’re going to Mars, you talk about ‘entry, descent, and landing,’ or EDL,” explains Arney. “Obviously, in our case, ‘landing’ would represent a significant failure of the mission, so instead we have ‘entry, descent, and inflation,’ or EDI.” The airship would enter the Venusian atmosphere inside an aeroshell at 7,200 meters per second. Over the next seven minutes, the aeroshell would decelerate to 450 m/s, and it would deploy a parachute to slow itself down further. At this point, things get crazy. The aeroshell would drop away, and the airship would begin to unfurl and inflate itself, while still dropping through the atmosphere at 100 m/s. As the airship got larger, its lift and drag would both increase to the point where the parachute became redundant. The parachute would be jettisoned, the airship would fully inflate, and (if everything had gone as it’s supposed to), it would gently float to a stop at 50 km above Venus’s surface.

Considering the whole world is focused on Mars these days, even the team behind the proposal notes it’s unlikely for the focus to shift anytime soon. But the project is still a fascinating pitch. Seriously, can you even imagine a real-life Cloud City? Lando would be proud. 

(Via io9, IEEE Spectrum)

Night sky just after sunset on March 24, 2012 with crescent moon and backlight, Jupiter, Venus and the Pleiades.

by Ritzelmut

Venus is the second closest planet to the Sun and has the highest surface temperature of any planet in our solar system, with an orbital period of about 225 Earth days. Because of its similar gravity and size, it is sometimes known as Earth’s “sister planet.” However, besides these two aspects, the two planets have almost nothing in common. With the densest atmosphere on any terrestrial planet in the solar system, the surface pressure on Venus is about 92 times that of Earth; the same pressure one kilometer beneath Earth’s oceans.

Even though Venus is comparatively much further away from the Sun than Mercury, it is the hotter planet with a surface temperature of around 462 °C; this is because of its dense atmosphere of greenhouse gases such as carbon dioxide and sulfur dioxide. One remarkable aspect of the atmosphere of Venus is the precipitation of liquid sulfuric acid. The surface geology of the planet has been observed by NASA for over twenty years now, and it is seen that there is extensive and violent volcanism at the surface.

(image sources: NASA; http://www.the8planets.com/wp-content/gallery/planet-venus/venus-atmosphere.jpg, http://www.boskowan.com/blanensko/)

Earth View from Moon by ric tan

On this day, but in 1974 the NASA spacecraft Mariner 10 made its closest approach to Venus.

Credit: NASA / Mariner 10

Please Build A Cloud City Over Venus 

The Surprisingly Strong Case For Colonizing Venus:

Why worry about building a colony on Mars when instead you could float one high above the surface of Venus? Science fiction writer Charles Stross recently revived the idea of building a Venutian colony when he suggested, cheekily, that billionaires ought to be compelled to donate to massive humanity-improving projects. He suggested two: a Manhattan Project-like focus on developing commercial nuclear fusion, or the construction of a floating city on Venus. 

The second planet from the Sun might seem like a nasty place to build a home, with a surface temperature hot enough to melt lead and an atmosphere so dense it would feel like being submerged beneath 3000 feet of water. But the air on Venus thins out as you rise above the surface and cools considerably; about 30 miles up you hit the sweet spot for human habitation: Mediterranean temperatures and sea-level barometric pressure. If ever there were a place to build a floating city, this would be it.

Believe it or not, a floating city might be a feasible project. Scientist and science fiction author Geoffrey Landis presented a paper called “Colonizing Venus” [PDF] at the Conference on Human Space Exploration, Space Technology & Applications International Forum in Albuquerque, New Mexico back in 2003. Breathable air floats in Venus’s soupy carbon dioxide atmosphere, which means on Venus, a blimp could use air as its lifting gas, the way terrestrial blimps use helium to float in our much thinner atmosphere.

This figure shows the volcanic peak Idunn Mons in the Imdr Regio area of Venus. The topography derives from data obtained by NASA’s Magellan spacecraft, with a vertical exageration of 30 times. Radar data (in brown) from Magellan has been draped on top of the topographic data. Bright areas are rough or have steep slopes. Dark areas are smooth. (NASA/JPL/ESA)

A group of science fiction authors and scientists have been discussing the idea on the blog Selenian Boondocks, which founder Jonathan Goff describes as “a blog I founded to discuss space politics, policy, technology, business, and space settlement.” One of the biggest problems with a lunar or Martian colony is that an astronaut’s bones and muscles deteriorate in low gravity. No one knows yet how much gravity a human needs to prevent deterioration, but Venus’s gravity is the closest to Earth’s, at about 9/10ths. Mars only has a third of the gravity that the Earth does, while the moon has a mere sixth.

Atmospheric pressure is also crucial. Think of the difference between jabbing a car tire and letting air out of a half-inflated balloon. Gases seek equilibrium. Since there’s barely any atmosphere on the moon or Mars, a rip in the hull of an enclosed human habitat would suck oxygen out at tremendous force. Thirty miles above Venus, it would merely seep out. This also means a Venutian cloud colony wouldn’t need as much reinforcement. Venus has other boons, too. Its rich atmosphere blocks radioactivity and could be mined for useful materials. And with a gentle temperature, far less energy would have to be spent on heating or cooling the colony.

Of course, it’s hard enough landing on the surface of another planet, let alone at 30 miles above the surface, but Landis hypothesized a way to do it.

A hypothetical floating outpost 30 miles above the surface of Venus. (Wikimedia Commons/Anynobody)

A sphere with titanium skin 0.04” thick would be able to survive reentry and float a couple of miles above the surface, he argued. Goff, who who describes himself as a space entrepreneur and space settlement advocate, suggests that rocket stages (the parts that drop off of a spaceship during liftoff) could also be engineered to float after use and be re-used, providing a way to and from the colony so that building materials could be mined from the surface. The well-informed space enthusiasts who frequent the Selenian Boondocks also helped Goff map out the chemical processes required to extract breathable air (a mixture of nitrogen and oxygen), water and various fuel and construction materials. 

After the chemical processes involved with producing life-supporting materials are demonstrated and perfected, the Selenian Boondocks team suggest small robotic labs could be sent to Venus, where they would bob in the atmosphere, extracting life-sustaining materials, gradually inflating great bladder-like structures (perhaps a Bigelow Aerospace module made of Kevlar). Years into the project, it might look like a gargantuan bunch of grapes. Permanent settlers could tether these floating blobs together, extending walkways and building platforms, creating something that might eventually look like a massive floating oil rig, complete with tubes dangling dozens of miles below to gather materials from the surface.

Goff plans to continue fleshing out the details on his site over the coming months (plans were temporarily put on hold after the birth of his youngest child). “I still need to talk about chemicals that seem easy to get to from the raw materials,” he says, “and how those impact colony design.”

As to what life perched high above Venus might really feel like, frequent Selenian Boondocks commentator George Turner imagines how a tough colonist might dangle meat into Venus’s ferocious, acidic atmosphere as a cooking source:

Well let me tell you, acid is good for meat, and breaks down connective tissue, fats, and tenderizes it. Run the pH the other way and it turns into soap and you might as well bite into a urinal cake.

Venus is not for the timid, or people too afraid to shove a fat bird out the airlock and let the harsh laws of thermodynamics do the work. Venus is for men. Men who like to eat meat – cooked in fire and acid and seasoned with the Devil’s own mix of volatiles boiled up from the pits of hell.

If the thought of Thanksgiving Dinner on Venus gives you the heebie jeebies, you don’t even need to think about plunging into the roiling atmosphere with nothing but a cheap plastic heat shield and a thin balloon to save you from the crematorium that yawns down below. So man up, dangle the bird into the depths of the Stygian hell, feast as someone who walks between worlds and lives on an airship that rides the hell born winds 30 miles above a surface so hot it glows visibly red.

Ultimately there will have to be a compelling reason to spend trillions of dollars to move off-world: a vital resource located on Venus, mass over-crowding, nuclear apocalypse. But if we do colonize the skies of Venus, it will be the soft factors like the plausibility of a Venutian acid-baked cuisine that will make us stay. 

So NASA won the internet today…

Computer-generated image of the surface of Venus using radar data collected from the Magellan spacecraft [1024 × 1024]

TODAY IN HISTORY: Planet Venus, observed by NASA’s Pioneer 12 space probe on February 26, 1979.