We’ve heard about the possibility of extraterrestrial life arriving on Earth from another planet, asteroid or comet, but the mode of transport usually includes a chunk of rock falling through the atmosphere as a meteorite. But there could be another form of interplanetary transportation. What if there are microbial forms of alien life floating in the upper atmosphere of Venus (the planet’s clouds contain compounds that could indicate presence of micro organisms)? Could they make the trip to Earth? Apparently it is possible, if Earth and Venus are correctly aligned, the solar wind may carry microbes from the upstream Venus to downstream Earth in a matter of days…
Earth and Venus are often referred to as ‘sisters’ as their size and geology are very similar. Although the Venusian surface may appear unsuitable for life to thrive (the temperature and atmospheric pressures are very extreme), it may be possible that microbial life exists in the clouds. As Nancy pointed out in her recent article about colonizing Venus, the environment 50 km above the Venusian surface is the most terrestrial-like in the whole of the Solar System (except Earth of course).
So it should come as no surprise that some scientists believe this may be a good location to search for the most basic forms of life. Two such scientists are Prof Chandra Wickramasinghe and Dr Janaki Wickramasinghe from the Cardiff Centre for Astrobiology, UK, who believe the chemical composition of Venus clouds are consistent with the presence of micro-organisms. Their research uses data from Venus Express (launched by ESA in 2005) which is currently orbiting the planet, trying to understand why Venus is so different from the Earth after 4.6 billion years of planetary evolution.
So the Wickramasinghe’s think that Venus and Earth are not only geologically similar, they may be biologically similar too. “Venus and Earth have often been referred to as sisters because of their geological similarities. Our research proposes that the two sisters may be biologically interconnected as well,” Chandra says. But they don’t stop there. If life does exist in the Venusian cloud tops, perhaps these micro organisms can survive the trip through space, seeding the terrestrial atmosphere. Naturally, this can only occur if the planets are in alignment, so the solar wind can erode the Venus atmosphere, transporting microbes as it does so.
However, the life on Venus theory has its critics. “The idea of life on Venus, particularly the clouds where the temperature and pressure are similar to the Earth, has been floated around for a while but is not really very likely,” says Prof Fred Taylor, a planetary scientist at Oxford University.
This is however an interesting field of research that may go to some way in explaining the phrase and book title: “Men Are From Mars, Women Are From Venus.” So, looking for life on Mars and Venus doesn’t seem so outrageous after all…
(A thank you goes to my friend Ross Fenion who sent me the lead to this story and made the “…Women Are From Venus” link, it wasn’t me…)