Venus Has Space Weather Explosions That Are Larger Than the Planet

A common space weather phenomenon on the outskirts of the magnetosphere, the magnetic bubble that surrounds the earth (and protects the surface of the planet from solar radiation) are "hot flow anomalies." These are, in effect, enormous explosions. NASA researchers recently discovered that the same phenomenon occurs on Venus, except that these giant explosions can be larger than the entire planet—and they can happen several times a day.

Venus Has Space Weather Explosions That Are Larger Than the Planet

"Not only are they gigantic," says Glyn Collinson, a space scientist at NASA's Goddard Space Flight Center, "but as Venus doesn't have a magnetic field to protect itself, the hot flow anomalies happen right on top of the planet. They could swallow the planet whole."

Collinson's conclusions are based on observations from the European Space Agency's Venus Express, which show just how large and how frequent this kind of space weather is at Venus.

Earth is protected from the constant streaming solar wind of radiation by its magnetosphere. Venus, however, has no protective magnetic shield. Why not? scientists ask. How and why did the two planets evolve so differently? What would earth be like without its magnetic field?

Venus' only protection from the solar wind is the charged outer layer of its atmosphere called the ionosphere. A sensitive pressure balance exists between the ionosphere and the solar wind, a balance easily disrupted by the giant energy rush of a hot flow anomaly. The hot flow anomalies may create dramatic, planet-scale disruptions, possibly sucking the ionosphere up and away from the surface of the planet—which sounds like a very good thing to not have happening to the earth.

Banner art by Ron Miller.