by Peter Jekel
All right, then, I’ll Go to Hell
Mark Twain
Venus has been known to humankind ever since our prehistoric ancestors first gazed skyward. It is the brightest object in the sky, only being outperformed by the Sun and the Moon. In fact it is so bright in the sky, that is can be seen both in the early morning and evening.
On the surface, Venus appears to be a twin of our home world, having similar density, size and mass but that is where the similarities end. Venus, the second planet from the Sun, can be described as a natural depiction of the Hell described in Christianity.
It was not always so. Due to the physical similarities to the Earth and its closer proximity to the warming Sun, Venus was seen not as a version of Hell, but as a veritable Garden of Eden. The perception persisted into the modern day. In 1918, Swedish Nobel-Prize winning chemist, Svante Arrhenius, theorized that Venus must be hot and humid and as a result covered in a thick mass of plant growth like the jungles of the Amazon. Due to its closer proximity to the Sun, it was theorized that the planet was not as far along in its development as Earth, due to a slower cooling, making it more like the Earth of around 200 million years ago, during the early days of the dinosaurs. Gustavus Pope’s 1895 Journey to Venus describes a trip to Venus not just by people, but by Martians, only to find a world filled with dinosaurs. Horror writer, H. P. Lovecraft and fellow author and medical doctor, Kenneth Sterling, wrote a tale, In the Walls of Eryx, in 1939, set on a jungle-covered Venus inhabited by a race of lizard men.
In 2006, writer S. M. Stirling wrote The Sky People about a jungle Venus set in another universe. Here in the alternate universe, Venus was terraformed by an alien race and then populated by not only dinosaurs but by Neanderthals a juxtaposition never seen on Earth except in poorly written Hollywood movies.
Dinosaurs or lizard people are not always an essential of a jungle-filled Venus. In the 1930’s,writer C. L. Moore, wrote a series of western style works called the Northwest Smith series. The Venus of this series is found to be dark and swampy and inhabited by a beautiful race of humanoids.
Some of the classic science fiction writers also wrote of a jungle Venus. Robert Heinlein’s Future History series describes a jungle-covered Venus. The Venus in Ray Bradbury’s short stories, The Long Rain and All Summer in a Day, describes a liveable Venus; however, it is pounded by almost ceaseless rain.
Some early scientists saw Venus, not as a jungle world, but as Panthalassa, an all-ocean world dotted with a few islands. In keeping with scientific thought of the day, several science fiction authors wrote of an oceanic Venus. Edgar Rice Burroughs, perhaps more famous for his Tarzan and Mars series wrote a series of stories in the 1930’s set on an oceanic Venus. Olaf Stapleton, in his epic tale, Last and First Men, depicts humans exterminating an aquatic intelligence found on Venus.
In 1943, C. S. Lewis in his Planet Trilogy series, describes Venus as a world covered in an ocean broken only by some rafts of vegetation. Leigh Brackett wrote a number of short stories between 1940 and 1949, Lorelei of the Red Mist, Enchantress of Venus and The Moon that Vanished, all set on a hot wet Venus covered with an ocean filled with exotic forms of alien life. Isaac Asimov in his early 1950’s Lucky Starr series, depicted Venus as an oceanic world filled with exotic aquatic life.
In 1965, Roger Zelazny wrote of Venus in his classic The Doors of His Face, The Lamps of his Mouth. Zelazny’s Venus is populated by fish-like creatures on the ocean world. Though the story is a good one, Zelazny committed a sin amongst true science fiction aficionados in that in 1965, we knew that Venus was not an ocean world at all.
Between 1924 and 1955, a writer named Ralph Farley, wrote the Radio Man series. It offers an interesting twist on an ocean-covered world of Venus. Farley’s Venus is covered by boiling oceans with habitable land populated by a humanoid race that are deaf, but instead communicate through antennae. To add to their insect characteristics, the race also possesses a set of vestigial wings.
There were some scientists who envisioned Venus in the early twentieth century not as a hot humid world but a hot and very dry world. American astronomers, Charles Edward St. John and Seth Nicolson, in 1922, observed the planet Venus and found that there was no spectroscopic evidence of either water or oxygen and came up with the idea of a hot dry Venus. This theory did not resonate as much as the jungle or ocean Venusian worlds, but it did find its way into a few early science fiction stories. One novella written by Poul Anderson in 1954, The Big Rain, and Frederick Pohl’s and Cyril Kornbluth’s 1952 The Space Merchants, are a couple of those stories set on a desert Venus.
As early as 1935, science fiction writer, Stanley Weinbaum combined all of the possibilities on his Venus. He wrote a couple of stories, Parasite Planet and The Lotus Eaters set on a tidally locked Venus with a hot barren desert on the sun-facing hemisphere, a hot wet jungle in the twilight area between the day and nightside and a frozen nightside. Inhabiting the twilight jungle zone are a number of different parasitic life forms which prove dangerous to humans.
All of these depictions of Venus were turned on their head when the first spacecraft from Earth made its entry into the realm of the hellish world. In December 1962 NASA’s Mariner 2 came to within 35,000 kilometers of the surface of Venus. The craft found that there was no intrinsic magnetic field, probably because it rotates too slowly to create a magnetic dynamo as we have on Earth; a Venusian day is over 243 Earth days long which is longer than its year of 223 Earth days. More importantly the temperature of the planet ranged between 217 to 317 Celsius, hardly temperatures for an ocean or jungle world. In 1970, the Soviet Venera 7 actually landed on the planet and recorded temperatures of upward of 450 to 470 degrees Celsius, hot enough to melt lead.
Perhaps the first science fiction author to write accurately of the new Venus shown by Venera and Mariner probes was Larry Niven. In his 1965 short story, Becalmed in Hell, a spaceship sent to the planet to explore the atmosphere is forced to land in order to fix a problem with the craft. Another story that depicts a very realistic version of Venus is Ben Bova’s simply titled Venus, about a couple of competing missions out to recover an astronaut’s body; the previous mission had failed for unknown reasons.
Mariner 2, though the first craft to successfully arrive at Venus, was not the first mission to Venus; that prize belongs to the Soviet craft, Venera 1 which arrived at the planet in February 1961. Unfortunately the vessel came to within only 100,000 kilometers of the planet’s surface before losing radio contact with Earth, thus returning no data.
The hot, corrosive and thick atmosphere of Venus is made up of predominately carbon dioxide with trace amounts of argon, carbon monoxide, sulphur dioxide and water. Atmospheric pressure at the planet’s surface is at about ninety times that of the Earth at sea level. For comparison, this is the equivalent of diving into the ocean to a depth of three thousand feet. Sealing off this pressurized inferno is a bank of sulphuric acid clouds (Venus does experience sulphuric acid rain, but the surface temperature is so hot, that the rain never reaches the surface but evaporates about sixteen kilometers above the planet) about seventy kilometers above the planet surface that whip around the planet at enormous speeds. In fact, those speeds are increasing and scientists are at a loss as to find a reason why, especially in light of Venus’ almost lethargic rotation. When the European Space Agency’s Venus Express arrived at the planet in 2006, it recorded cloud top speeds of up to 300 kilometers per hour. Over the course of the mission, in 2014, it was found that wind speeds had increased to up to 400 kilometers per hour.
Venus has often been described as a planet depicting Earth’s distant future, with a greenhouse effect running amok. If humans pump greenhouse gases into Earth’s atmosphere at present rates, it will only be a matter of time before Earth starts down an irreversible trend toward a true Venusian atmosphere. In fact, there may be something to the theory. It has been calculated that if all of the carbonates locked up in rocks of the Earth were released as carbon dioxide, Earth’s weather would likely be very similar to that of Venus today. Conversely, if we were able to lock up the carbon dioxide of Venus into carbonate rocks, Venus’ climate would likely be more like that of present-day Earth.
There have been over twenty-six missions and flybys of Venus and all have contributed a lot to our knowledge of the planet, but it was NASA’s Magellan mission that began its orbit of the planet in August of 1990 that provided some very unique observations. During its tenure around the planet, the probe’s radar mapped the surface of Venus at resolutions of better than one hundred meters before losing radio contact in October of 1994. It also did a gravitational profile of the planet allowing scientists to “see” the interior.
Magellan discovered what could be described as a genuine geological wonderland. It is the most geologically active planet in the solar system. Unlike Earth, Venus has numerous tectono-volcanic structures. They differ from the volcanoes that we have here on Earth. Volcanoes on our planet form along faults in the crust and are mainly just masses of lava.
A tectono-volcanic structure, on the other hand, is formed by the process of faulting that happens over the magma rising from below. Coronas are one type of such structure and Venus is home to over three hundred of them. They are the largest of such tectono-volcanic structures ranging from one hundred to one thousand kilometers across; the average is around 250 kilometers. They are round to oval in shape surrounded by a ring of faults or ridges. They are topped in the centre with a range of structures, ranging from flat, raised or collapsed centre. Arachnoids are another tectono-volcanic structure very similar to, but somewhat smaller than the coronas. There are about 250 of them on the planet. Then there are the novae, about fifty of them on Venus, which range from fifty to three hundred kilometers across. They tend to form over mantle plumes on the higher plains.
In addition to the tectono-volcanic structures of Venus, there are, like on Earth, true volcanoes. Venus actually is home to the most volcanoes of any world in the solar system. Most of the volcanoes are shield volcanoes, but there are some other non-shield ones as well; non-shield volcanoes produce a thick viscous lava, whereas a shield volcano have very fluid lava flows like the volcanoes of Hawaii.
Venus is home to about 100,000 smaller shield volcanoes often twenty kilometers across or less. These smaller volcanoes tend to be found clustered on the planet’s lowland plains. Medium size volcanoes range between twenty and one hundred kilometers in size. There are about 270 such volcanoes on Venus and only about seventy of them are shields. Ranging between one and six hundred kilometers across and reaching an average of 0.3 to five kilometers in height, about 150 large shield volcanoes can be found on Venus. The largest is Sif Mons which reaches a total of two kilometers in height but over three hundred kilometers in diameter.
Earth may be covered with an extensive network of river basins carved out by water. On Mars we also find a number of apparent channels that appear to have formed when the planet was wet. Venus has a number of flowing channels as well, but they are not filled with water but with lava. Some can reach up to a kilometer and half in width and stretch up to four hundred kilometers in length. There is one flow that is longer than the Nile River, the longest river on Earth.
Whereas all of the volcanic activity on Earth is driven by plate tectonics, Venus does not appear to have any such geological mechanism at work. Plate tectonics is based on the fact that the crust of the Earth is divided into a series of rigid plates that float atop a viscous underlayer of the mantle. Where these plates meet is where the volcanoes and often earthquakes happen.
Instead, Venus’ volcanism is driven by mantle hot spots. Earth has some of these hot spots as well but they are few and far between. Plate tectonics is also the process whereby the mountain ranges of Earth are formed. Venus, however, has a series of complex ridges called tesserae, in the highlands. How they are formed without the mechanism of plate tectonics is not known.
Though erased by a number of activities such as wind and water, plate tectonics has also played a role in the erasing of craters on Earth. Without plate tectonics, there is also a remarkable lack of craters on the Venus’ surface. This can be partially explained by the higher wind speeds and the thick protective atmosphere of the planet, but there should be more craters in the absence of plate tectonics. One theory to explain this is nothing short of amazing. Venus is theorized to have a thick crust in which the intense heat builds up but cannot escape into space partly due to the thickness of the crust but also the thick atmospheric cloak around the planet. Every 750 million years the surface of the planet actually flips to displace the heat, but in the process gradually building up an ever-thickening crust further compounding the difficulty in releasing heat.
Venus also has a few other oddball features For example, it is the only body in the solar system that has a retrograde spin on its axis. Why this should be is possibly due to an early asteroid hit early in Venus’ past. Earth, too, was hit by a large object early in its history which resulted in the Moon that hangs in our sky. Venus did not acquire a moon, but instead absorbed the impact which not only increased its mass but possibly a reversal of its axial spin.
Venus sounds like a world that is truly inhospitable to life, but just maybe, there is life there. Is there any evidence of this? Based on the extreme temperatures, it is probably unlikely that any water-based life as we know it here on Earth is possible, at least on the planet’s surface. There is however, the upper atmosphere of the planet where temperatures are lower, that life may be possible.
Several of the twenty-six missions to Venus detected a number of interesting chemicals in the atmosphere, about fifty kilometers above the surface, that may be signatures of life. The Soviet Venera, NASA’s Pioneer Venus and Magellanprobes discovered hydrogen sulphide, sulphur dioxide, chlorine and carbonyl sulphide. The carbonyl sulphide holds scientific interest in particular since it is difficult to explain being produced inorganically; however, since its presence can be produced by volcanism and since Venus is so volcanically active, life may not be needed to explain its origin in this case.
Recently scientists have discovered phosphine gas in Venus’ atmosphere. A team from the James Clerk Maxwell Telescope in Hawaii analyzed the data and found the stinky gas in appreciable amounts, up to twenty parts per billion. Ironically, the gas is deadly to most life on Earth, in spite of it being a potential biosignature; it is formed by anaerobic bacteria found in environments without oxygen. Anaerobic bacteria can be found in a number of places from sewage, to swamps, to landfills to the interior of animal and human guts. There are a couple of theories as to where the gas is coming from and the one that seems to fit the findings the best is that it due to the presence of anaerobic life. It could also be due to some other form of chemical reaction but researchers cannot find any known reaction that fully fits the bill, including volcanoes, solar winds and even tectonics. What makes the discovery confounding is the fact that phosphine is a gas that is destroyed by both sulfuric acid which is abundant in the atmosphere as well as sunlight, so the source of the gas is not from the ancient past. It is being produced presently.
Life on Venus was something that many writers of science fiction envisioned and in a number of cases that life is intelligent. In 1897, John Munro published A Trip to Venus, about an engineer and his daughter who travel in his newly invented flying machine to the inner planets of both Mercury and Venus. On Venus they discover a Utopian civilization.
Also in 1897, Fred Jane wrote a satire, To Venus in Five Seconds, about a Venus populated with an alien race that can be best described as a cross between such diverse creatures as elephants and flies. As an aside, Fred Jane is also the author of the famous military machine series, which began with Jane’s Fighting Ships. The famous editor of the Astounding Science Fiction (later changed to Analog Science Fiction and Fact), John W. Campbell, wrote all to few stories but one of them, was published in 1930. It was about a Venus with a highly advanced civilization.
Other authors have departed from humanoid intelligence and looked at other options. In 1975, Brenda Pearce wrote a short story, Crazy Oil, about an intelligence on Venus that is based on hydrocarbons. A more recent novel is James Corey’s 2012 Caliban’s War, about a Venus with an intelligent life form unlike anything one had thought of before; it is a described as a protomolecule; a protomolecule is best described as a virus which, in turn, is essentially a series of genetic instructions. Philip Reeves wrote an alternate universe tale, Larklight. In the story, Venus is covered with a large number of plant species, some of which are intelligent.
What about the past? Is it possible that before Venus’ temperature and pressure reached the heights that we observe today, that life existed. It is possible but the fact that, unlike the surface of Mars that appears to retain a number of its surface features for millennia, the surface of Venus is in constant flux due to its volcanism and its crustal “flip” that it is unlikely that we will ever discover those signatures of life on the present day surface. Then, again, never say never. Future missions may prove this hypothesis wrong.
Venus as a potential for future human colonization has advantages. The planet has many similarities to Earth including a similar gravity to that of Earth, essential for human physiology. It is the closest planet in the solar system to our planet making support from Earth easier to provide. However, this is where the advantages end and the hot thick blanketing atmosphere makes the planet less attractive as a colonization goal.
The surface of Venus may have its limitations, but what about the thick atmosphere? Geoffrey Landis of NASA’s Glenn Research Center extrapolated from earlier ideas of Soviet scientists and has suggested that we may be able to colonize Venus by living in the clouds. At around fifty kilometers from the surface, Venus provides the most Earth-like conditions of any world in the solar system though wind speeds are around 340 kilometers per hour. This speed is far faster than the rotation of Venus, which in turn, may have some advantages for human colonists by providing a shorter day than the 243 Earth days of a normal Venusian day. By floating freely a balloon type structure, the colony would also be spared some of the hazards of the high winds.
As early as 1909, one science fiction author thought of the possibility of cloud-based societies on Venus. American astronomer Garrett Serviss wrote "A Columbus in Space," a tale of a Venus populated by two telepathic races. One lived in caves and the other in a floating city in the sky. Geoffrey Landis, one of the chief architects of the idea of a colony in Venusian clouds, also published his ideas in a short story, The Sultan of the Clouds, where humans colonize Venus by living in balloon floating in Venus’ sky.
What about the terraforming of the planet? Unlike terraforming Mars with its low pressure and temperature, Venus would present the exact opposite problems. A way to remove or convert the dense carbon dioxide shroud of the planet would have to be considered. Several ideas that have been tossed around by scientists. A. E. van Vogt in his classic Null-A series written in the late 1940’s and early 1950’s, the Venus of the far future has been terraformed into the jungle world depicted in earlier tales set on Venus.
One way to terraform the planet includes the reduction of solar radiation reaching the planet. This could be accomplished by the positioning of deflecting space mirrors or possibly solar shades. Science fiction writer, Kim Stanley Robinson, in his novel, 2312, describes a giant parasol that is used to block the sun, thus cooling the planet to a point where the carbon dioxide is frozen out of the atmosphere and then covered with rock to prevent the carbon dioxide does not re-enter the atmosphere. It is not the first time that Robinson has used this science for his ideas on the terraforming of Venus. In his novel, Blue Mars, the last installment of his Mars series, it is described that humans are planning to deploy a parasol to deflect sunlight while mechanical drivers are installed to slow the axial rotation of Venus.
Kim Stanley Robinson wrote the classic Mars series that depicted over several novels, the gradual terraforming of Mars. Pamela Sargent did exactly the same thing with Venus, writing a series of novels, Venus of Dreams, Venus of Shadows and Child of Venus, about its gradual terraforming.
Carl Sagan, in 1961, suggested the creation of genetically modified bacteria to fix carbon of carbon dioxide of Venus’ atmosphere into organic compounds. This idea fell out of fashion due to another limitation ironically identified by Sagan. The atmosphere of Venus lacks enough hydrogen which would be essential for the carbon fixing to occur.
Another idea has been proposed again by Sagan and his partner J. B. Pollack is to physically remove the atmosphere of Venus to reduce its density to make the planet livable. This could be done by the impacting of the planet with a seven hundred kilometer diameter asteroid which would blast much of the atmosphere into space. Arthur C. Clarke, in his 3001: The Final Odyssey, used the concept of steering cometary material into Venus to lower its temperature. Unfortunately, for this hypothesis it is possible that the ejected gases could be recaptured by the gravity well of Venus thereby re-creating the thick atmosphere again.
Even if Venus did not resorb its original atmosphere, there is still the problem of the slow rotation of the planet. Without a dense atmosphere, the temperature differences of the night and day side of Venus could become another problem that future colonists would have to contend with. It is possible that the planet’s rotation could be sped up through the precise flybys of cometary or asteroid bodies through the transference of angular momentum. One variation of this idea has been suggested by astronautical engineering consultant, G. David Nordley in a short story, The Snows of Venus, that he had published in the magazine, Analog. In the story, he suggested the launching of mass payloads from Earth using mass drivers into Venus’ orbit to speed up its rotation. Stephen Baxter in his Manifold: Space, describes the use of a planet-covering superconducting cable to speed up the rotation of Venus.
At least one author wrote a cautionary tale of the terraforming of Venus, but it comes with a dire consequence. Pion by Dutch author, Felix Thijssen story is about the terraforming of Venus by the seeding of the clouds with photosynthesizing organisms but by doing so condemn a sentient form of life on the planet, the jellyfish-like Venusians, to death as oxygen is toxic to them.
Other science fiction authors have suggested that perhaps there are technologies that will allow humans to survive on Venus other than terraforming. In Frank Herbert’s Man of Two Worlds, soldiers of the French and Chinese armies who are fighting one another on the surface of Venus, wear suits made of a material that allows them to survive the planet’s extreme conditions. John Varley, in his short story, In the Bowl, writes of several technologies that will allow humans to survive on Venus.
Other science fiction writers have suggested living underground to avoid the extreme surface conditions of Venus. In an early novella by James Gunn, The Naked Sky, human colonists have partially terraformed the planet, but must live underground as the atmosphere continues to be toxic. Frederick Pohl, in his The Merchants of Venus, has humans surviving on Venus, by living underground in tunnels. The tunnels, however, were not made by humans, but by the Heechee, aliens that can be found in a number of other Pohl’s writings.
Venus has a lot to attract us to explore her further and space agencies around the world have the planet on their agenda. NASA has proposed a launch in 2022 of the Venus In-Situ Explorer. Its goal for the brief lifespan of the lander on the planet surface will be to draw up a core of the planet material unaffected by the harsh conditions on the planet surface. The European Space Agency is looking at the launch of the Venus Entry Probe around 2022 as well. Its mission will be to explore the almost Earth-like conditions of the atmosphere at around fifty kilometers above the surface. The Russians have an extensive history of the exploration of Venus with their Venera program (sixteen craft between 1961 and 1984). They are now proposing to launch in 2026, the Venera-D craft with the main purpose of radio mapping of the surface of Venus, with a radar more powerful than a previous mapping mission to Venus, NASA’s Magellan mission.
It would appear that our “twin” in the solar system really is not one at all. At first appearances, it seems promising which is why many early scientists and writers depicted a virtual Garden of Eden in their work. As scientists continue to strip away the cloak of Venus through space missions and further refined observation techniques, we find a world that is the exact opposite of the Garden of Eden. Instead we find it as the world that Dante described in his epic poem, Inferno, the centre of Hell.
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