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Venus’ Water-Sucking Electric Winds Are Frightening
published during a waning crescent moon.
06/28/2016

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Credit: NASA/Conceptual Image Lab

Venus is our planet’s rebellious twin. Unlike our bright atmosphere, hers is stifling with sulfuric light shows and terrifying storm winds. Despite being shrouded, Venus’ arid gales are now less of a mystery: new research has discovered that her electric winds are so powerful, they’ve sucked the water right off the planet.

But what are electric winds, if not the time-travel bolts that sent Bill and Ted on their excellent 1989 adventure?

Bill Ted

Credit: De Laurentiis Entertainment Group

Unlike Earth where water shimmers across most of the surface, Venus is dehydrated. It’s so dry, researchers estimate that Venus has tens of thousands of times less water than Earth. Venus’ thick atmosphere traps so much heat, its surface is a broiling 860 degrees (or 460 degrees Celsius), which also happens to be a good temperature to bake a pizza on Earth. Along with the immense atmospheric density, the surface is hot enough to melt lead.

But evidence shows that Venus may have had oceans of water. That led to the next head-cocking question: If the water is not in the atmosphere, where did all of that steam go? A recent study points to planet’s electric field.

Venus’ field is at least five times that of Earth’s, but it was hard to detect until now because it still only has the power of a single wind turbine spread out over hundreds of miles, says lead author Glyn Collinson.

Venus field

Credit: NASA Goddard

Every planet has a gravity field, which pulls things toward it, including the atmosphere. For something like water to be removed from gravity’s tug, it needs some serious force.

For a while, astronomers suspected that planets with atmospheres have weak electric fields. An electric field is created above a planet when electrons (which are lighter than protons and other ions) sail up into the atmosphere as they are less burdened by gravity than their ionic comrades. However, electrons still attached to their heavier, positive buds cause them to linger in the planet’s atmosphere, creating an electric field blanket.

(Quick reminder: An electric field is not the same as a magnetic field. A planet’s magnetic field deflects the sun’s highly charged particles like an invisible shield. Earth’s evolved from its iron core. Venus’, on the other hand, is so weak, it’s insignificant.)

So what stripped all of that water off of Venus? In short: a monster force, Collinson explains — one that can rip out heavy things. “If you were unfortunate enough to be an oxygen ion in the upper atmosphere of Venus then you have won a terrible, terrible lottery,” he said in an announcement. “You and all your ion friends will be dragged off kicking and screaming into space by an invisible hand, and nothing can save you.”

This changes how we think about planets, Collinson says, because if we look for habitable planets around other stars, it’s no good having Earth-like conditions if an invisible force can suck things like oxygen into space with an assist from solar wind.

And that can change exoplanet missions like Kepler, the authors conclude, as well as the parameters of what inhabitable really means — even though Bill and Ted would still probably find visiting them pretty excellent.