We do an awful lot of talking about Mars, and sometimes it seems like we forget about Earth’s closest neighbor, Venus. That needs to change, because it is just as interesting as the Red Planet. They call Venus the Morning Star, because it can still be seen with the rising morning sun. Oddly, enough the Morning Star in Latin is Lucifer, and some Christian traditions have linked the word with the Devil. Maybe that is appropriate, as Venus’ surface it is comprised of sulfuric acid clouds, and temperatures that can reach 462 degrees Celsius or 864 degrees Fahrenheit. So basically it’s hell, but recent studies have found that the planet may not have always been like that. In fact, in the ancient past it may been something better suited for a goddess of love than the representation of evil incarnate. Either way, maybe its time we get a closer look.
Venus de Melting Pot
Venus takes 224 days to orbit the Sun. On average the planet is 40 million kilometers or 25 million miles away from Earth, making its closest approach every 584 days. Compare that to Mars, which when at its closest to Earth is still 54.6 million kilometers or 33.9 million miles away from us. The planet Venus is also roughly the same size as ours, about 12,104 kilometers or 7,521 miles in diameter, which is 0.95 times that of the Earth. It’s mass is also 0.81 times that of our home. Both planets seem to be relatively young -cosmological speaking- but our closest neighbor rotates slower than Earth and in the opposite direction as we do. It takes about 117 Earth days for the planet to complete one rotation.
However, what most people talk about when they talk about Venus is its thick greenhouse atmosphere. The planet has several kilometers of deep layers of clouds, mostly comprised of sulfuric acid. It contains about 0.1 to 0.4 percent water vapor, and 60 parts per million free oxygen. The atmosphere is made up of mostly carbon dioxide, and according to findings by two Russian Venera probes lightning is extremely common. Massive electrical strikes happen about 10 times per second in the Venusian atmosphere. The surface -if you can reach it- is mostly of rolling hills and active volcanoes. The highest peak is 11 kilometers or 6.8 miles, and is located in the Maxwell Mountains. It is also worth noting that these mountains -named after astronomer James Clerk Maxwell- are the only features of the planet named after a man. The majority of features on the planet are named after women, as per the rules set down by the International Astronomical Union. Most scientists believe that the Venus has tectonic plates, like those on Earth, and the core of the planet is iron surrounded by a molten rock mantle. However, unlike Earth Venus doesn’t have a magnetosphere, which means it is more exposed to cosmic radiation and solar activity.
Venus not Venice
However, our neighbor wasn’t always the hellish landscape of heat, volcanoes, and death that it is today. A recent report suggests that for 2 billions years of its early history Venus may have been a heck of a lot like Earth. Shallow oceans, puffy white clouds, and possibly even sufficiently temperate climates to create life. The trace amounts of water vapor in the atmosphere always hinted that the planet could have once had oceans, but most scientists believed that Venus was too close to the sun to sustain liquid water for long, believing that constant evaporation would have proved too large a problem. However, recent computer modeling seems to confirm that it would have been possible even with the planet’s slow rotation.
This also hints that 2 to 3 billion years ago the sun may have been 30% dimmer, thus easing the evaporation effects for the young planet. Even so Venus was still receiving about 40% more sunlight than Earth does today, but according to some scientists those conditions would have still resulted in a stable, warm, and wet climate that would have created thin a cloud cover that blocked UV radiation and kept the surface a few degrees cooler than modern Earth. Venus’ current state is theorized to be a result of several factors. First the increasing brightness of the sun would have certainly sped up the evaporation cycle. The ultra-violet radiation breaks down the water vapor and releases hydrogen into space, which has led to a carbon dioxide build up over billions of years. Also, intense volcanic activity in the lowland regions was very likely a big contributing factor. This all would have resulted in a feedback loop that sped up the process even further. Thus, the greenhouse gases grew out of control and resulted in the thick and acidic atmosphere of today.
Home Sweet Venus
Of all the planets Venus is the first planet humans ever sent probes to, starting in 1961, but penetrating the clouds has always proven to be difficult. There have more than 20 missions to Venus, and a lot of unsuccessful ones. The most interesting missions tend to be the Soviet Venera missions between 1961 and 1983. They included orbiters, landers, and even balloons to study the atmosphere. Most probes could not survive more than an hour inside the planet’s atmosphere, even those designed for intense heat and pressure quickly succumb to the hellish conditions. That means we do not have anything on Venus comparable to Curiosity or the other Mar’s rovers, but we do actually have some pictures of the surface… Yes, we know what the surface of Venus looks like and you can Google it.
Yet, despite the incredibly hostile conditions there is a growing contingent of NASA scientists that believe the planet might be ripe for manned missions, and even colonization. In a now famous report by Geoffrey Landis, it is suggest that humans don’t colonize the surface but the skies of our sister world. At about 50 kilometers or 30 miles above the surface the planet’s atmosphere is the most Earth-like place found in the solar system- outside of… you know… Earth. Floating zeppelins would allow scientists to conduct research, live, and work, on a planet that has similiar gravity, atmospheric pressure, and even enough protection from solar and cosmic radiation to provide for relative safety for the people living and working there. Additionally, since oxygen is lighter than the Venusian atmosphere, the balloons could float and be breathable for the colonists at the same time. The entire area of the blimps could be habitable for explorers.
Venus’ relative proximity to Earth compared to Mars, also means that travel times would be decidedly less. The missions would be cheaper and have less transit time through space for humans. That is a good thing, as one of the biggest technological challenges we are having with a Mars mission is the amount of cosmic radiation that astronauts will be exposed to during the 6 to 8 month transit period. Going to Venus would only takes 3 months using today’s technology. That is still not ideal but it does mean that humans are left exposed for less than half the time. Also -and we’re just going to throw this out there- we could have Cloud City.
All in all whether you think Venus is a love goddess or a living hell, you have to admit that it’s a pretty interesting place. Who knows maybe we might even live there someday. Just call us Lando Calrissian.