|A dirigible approaches an outpost within the ambiance of Venus. Picture credit score: NASA.|
There is no award for “Most Imaginative Area Engineer,” but when there have been, Geoffrey Landis will surely be a high contender. In reality, if such an award is ever created, it ought to maybe be named the Geoffrey, in parallel with science fiction’s Hugo Award, which owes its title to pioneering creator, editor, and writer Hugo Gernsback. Not by the way, Landis owns a pair of Hugos; he acquired his first in 1992 for “A Stroll within the Solar,” a brief story set on the Moon, and his second in 2003 for his story “Falling Onto Mars.”
Landis is an engineer at NASA’s Glenn Analysis Heart (GRC) in Cleveland, Ohio. A lot of his NASA work has centered on vitality techniques, with an emphasis on photo voltaic photovoltaic energy.
In a short paper ready for the February 2003 Area Expertise and Purposes Worldwide Discussion board in Albuquerque, New Mexico, Landis made a compelling case for Venus, not the Moon, nor Mars, nor a twirling sphere, torus, or tube in open house, as the best place to determine an off-Earth human settlement. Particularly, he set his sights on the Venusian ambiance simply above the dense sulfuric-acid clouds. Landis referred to as it “essentially the most earth-like surroundings (apart from the Earth itself) within the Photo voltaic System.”
Most individuals consider Venus as a hell planet as a result of they assume solely of its floor. By about 1960, scientists utilizing Earth-based devices had decided that Venus had a temperature of 342° C (648° F). Many, nevertheless, refused to imagine that Venus may very well be so scorching. Some tried to discover a loophole: they hypothesized that the Venusian ambiance was scorching whereas its floor was cool sufficient for liquid water and life.
Mariner 2, the primary profitable interplanetary spacecraft, flew previous Venus in December 1962. Its crude scanning radiometer discovered a decrease temperature — round 230° C (450° F) — although one nonetheless a lot greater than most planetary scientists anticipated. Mariner 2 additionally decided that air stress on the Venusian floor was at the least 20 instances Earth sea-level stress.
For greater than 20 years, Venus was the Soviet Union’s favourite Photo voltaic System exploration goal. The Venera landers decided that its floor is manufactured from basalt, a volcanic rock. Additionally they discovered that the imply atmospheric stress on the floor is 96 instances Earth sea-level stress and that the floor temperature averages about 462° C (863° F) with comparatively modest day/night time, latitude, and altitude variations.
The Venusian atmospheric temperature, however, was discovered to fluctuate considerably with altitude, a proven fact that the Soviet Union would put to good use. In June 1985, the Vega 1 and Vega 2 spacecraft launched armored landers and frivolously constructed rubber balloons as they flew previous Venus on their solution to Comet Halley. The Vega 1 lander touched down however returned minimal information. Vega 2 landed efficiently and survived the hellish floor situations for 56 minutes.
The dual three-meter-diameter, helium-filled balloons deployed between 50 and 55 kilometers (31 and 34 miles) above the Venusian floor — that’s, simply above the cloud-tops, within the zone Landis noticed as promising for human settlement. Their small instrument payloads transmitted information for roughly two days — till they exhausted their chemical batteries.
In that point, the balloons rode the carbon dioxide winds from their deployment factors over the nightside into vibrant Venusian daylight. The Vega 2 balloon travelled about 11,100 kilometers (6900 miles) and the Vega 1 balloon travelled 11,600 kilometers (7210 miles). When their instrument payloads exhausted their batteries, the balloons carrying them confirmed no signal of imminent failure. They could have lasted for months and even years.
|Vega-type balloon on show on the Nationwide Air and Area Museum’s Udvar-Hazy Heart in northern Virginia, simply exterior Washington, DC. Picture credit score: Geoffrey A. Landis.|
The delicate balloons may final so lengthy as a result of 50 kilometers above Venus, simply above the cloud tops, the temperature ranges from between 0° C to 50° C (32° F to 122° F) and the atmospheric stress approximates Earth sea-level stress. A skinny cloth cowl was ample to defend every balloon from sulfuric acid droplets drifting up from the cloud layer.
Venus settlers would float the place Vega 1 and Vega 2 floated, however Landis rejected helium balloons. He famous that, on Venus, a human-breathable nitrogen/oxygen air combine is a lifting fuel. A balloon containing a cubic meter of breathable air could be able to hoisting about half a kilogram, or about half as a lot weight as a balloon containing a cubic meter of helium. A kilometer-wide spherical balloon crammed solely with breathable air may within the Venusian ambiance carry 700,000 tons, or roughly the burden of 230 fully-fueled Saturn V rockets. Settlers may construct and dwell contained in the air envelope.
The air envelope supporting a settlement wouldn’t essentially keep a spherical type. Lack of any stress differential would enable the fuel envelope to vary form fluidly over time. It could additionally restrict the hazard ought to the envelope tear. The inner and exterior atmospheres would combine slowly, so the settlement ambiance wouldn’t all of the sudden flip toxic, nor would the settlement quickly lose altitude.
A restore crew wouldn’t require stress fits, Landis defined. They’d, after all, want air-tight face masks to offer them with oxygen and maintain out carbon dioxide; including goggles and unpressurized protecting clothes would maintain them protected from acid droplets.
Acid droplets within the Venusian ambiance would little doubt be annoying, however Venus would lack the frequent poisonous mud storms of Mars. Orbiting practically twice as near the Solar as does Mars, a Venusian photo voltaic farm would have out there 4 instances as a lot photo voltaic vitality always — and with no mud storms to get in the way in which. Landis famous that photo voltaic panels may accumulate virtually as a lot daylight mirrored off the brilliant Venusian clouds as they may from the Solar itself.
Mars, the Moon, and free-space habitats all should take care of photo voltaic and galactic-cosmic ionizing radiation. A settlement 50 kilometers above Venus, against this, may depend on the Venusian ambiance to keep at bay harmful radiation. Radiation publicity could be nearly equivalent to that skilled at sea stage on Earth.
Many aspiring house settlers assume that people and the crops and animals they depend on (or just prefer to have round) will be capable to dwell in one-sixth or one-third Earth gravity — the gravitational pull felt on the Moon and on Mars, respectively — with no ailing results. The exhausting actuality, nevertheless, is that nobody is aware of if that is true. It’s attainable that astronauts dwelling in hypogravity — that’s, gravity lower than one Earth gravity — will expertise well being results much like these they expertise throughout lengthy stays in microgravity (for instance, on board the Worldwide Area Station).
Venus is almost as dense and as giant as Earth, so its gravitational pull is about 90% that of humankind’s homeworld. The probability that hypogravity will make long-term occupancy unhealthful would possibly thus be diminished.
The Venusian ambiance is wealthy in assets wanted for all times and the Venusian floor, whereas hellish, would lay solely 50 kilometers away from the settlement always. Landis urged that Venus settlers would possibly use a suspended super-strong cable to carry silicon, iron, aluminum, magnesium, potassium, calcium, and different important chemical components to the floating settlement. He famous that laboratory experiments geared toward producing robots hardy sufficient to operate on Venus for lengthy intervals had already begun; operators would possibly use such rovers to remotely mine the floor from the consolation of the floating settlement.
Landis pointed to the Primary Asteroid Belt between Mars and Jupiter as a possible supply of assets for Venus. He famous that any given asteroid within the Primary Belt is simpler to succeed in from Venus than from the Earth or Mars. A spacecraft launched from Venus on a minimum-energy trajectory can, for instance, attain resource-rich 1 Ceres, the biggest asteroid, in rather less than an Earth 12 months; a minimum-energy journey from Earth to 1 Ceres would want slightly greater than an Earth 12 months.
|Picture credit score: NASA.|
The massive Primary Belt asteroids are the truth is typically positioned farther away from one another than they’re from Venus. Additionally they orbit the Solar way more slowly: 3 Vesta wants 1325 Earth days to circle the Solar as soon as; 1 Ceres wants 1682 Earth days; 2 Pallas, 1686 Earth days; and 10 Hygeia, within the outer a part of the Primary Belt, 2035 Earth days. Which means that minimum-energy switch alternatives between Primary Belt asteroids happen years and even a long time aside. Alternatives for minimum-energy transfers between Venus and any Primary Belt asteroid, however, happen about as soon as per Venus 12 months (that’s, about as soon as each 225 Earth days).
Because the journeys of the dual Vega balloons illustrate, Venus ambiance settlements would journey quick winds. These close to the equator would circle the planet each 4 days. This may imply, Landis defined, that they might expertise a day/night time sample of two days of darkness adopted by two days of sunshine. He anticipated that settlements looking forward to a extra Earth-like lighting sample may migrate to the Venusian circumpolar areas, the place a circuit across the planet could be shorter.
If many “cloud cities” had been finally established within the ambiance of Venus, then a choice for the poles would possibly result in crowding. If, however, any latitude had been honest sport, then Venus would supply for settlement a complete space 3.1 instances Earth’s land space — that’s, greater than thrice higher than the floor space of Mars. Landis wrote that, finally, a “billion habitats, each with a inhabitants of a whole lot of hundreds of people, may. . . float within the Venus ambiance.”
Mariner Venus 1962 — Last Undertaking Report, NASA SP-59, NASA Jet Propulsion Laboratory, 1965.
Soviet Area Packages 1980-1985, Nicholas L. Johnson, Quantity 66, Science and Expertise Collection, American Astronautical Society, 1987, pp. 186-188.
“Colonization of Venus,” Geoffrey A. Landis, Area Expertise and Purposes Worldwide Discussion board (STAIF) 2003, Albuquerque, New Mexico, 2-5 February 2003; American Institute of Physics Proceedings 654, Mohamed S. El-Genk, editor, 2003, pp. 1193-1198.
Centaurs, Soviets, and Seltzer Seas: Mariner 2’s Venusian Journey (1962)
Venus as Proving Floor: A 1967 Proposal for a Piloted Venus Orbiter
Floaters, Armored Landers, Radar Orbiters, and Drop Sondes: Automated Probes for Piloted Venus Flybys (1967-1968)
Two for the Value of One: Eighties Piloted Missions with Stopovers at Mars and Venus (1968)
A number of Asteroid Flyby Missions (1971)
Footsteps to Mars (1993)