REAL LIFE NEWS: WHY IS VENUS SO DRY?
by Hazed
When I starting to read science fiction as a child, the books I read put colonies on Venus, imagining the planet to be a hot, rainy, jungly sort of place with a perpetual cloud cover. It wasn’t until the late 1950s that radio observations became sophisticated enough to see that the planet had amazingly hot temperatures, up to 600 degrees K, around the melting point of lead. Sadly that meant no more Venusians and no human colonies on the planet.
Now we know that Venus is bone dry. It has a thick atmosphere surrounded by hazy clouds, but no oceans, seas or rivers. While there is some water trapped in the atmosphere as steam, but despite the planet being of a similar size and gravity to Earth, there’s between 10,000 and 100,000 times less water than our planet’s atmosphere.
Now, scientists think they know why. They have found that an ‘electric wind’ whisks away the water in Venus’ atmosphere. When water molecules rise to the top of the atmosphere, the sunlight splits them into ions and the planet’s strong electric field (five times greater than Earth’s) accelerates the charged ions to such high speeds that gravity can’t contain them. The ions whizz off into space, lost forever.
“It’s amazing and shocking,” said Glyn Collinson, a scientist at NASA’s Goddard Space Flight Center and lead author of the study.
“We never dreamt an electric wind could be so powerful that it can suck oxygen right out of an atmosphere into space. This is something that definitely has to be on the checklist when we go looking for habitable planets around other stars.”
So that’s why there are no Venusians.
Source: http://www.theregister.co.uk/2016/06/20/electric_winds_on_venus/
