February 21, 2014
Space Weather Around Venus Is Harsher Than That Around Earth
[ Watch the Video: What's Causing Crazy Weather On Venus? ]
Lee Rannals for redOrbit.com - Your Universe Online
Scientists have discovered that the space weather around Venus can have such large explosions that they are bigger than the entire planet. They also said that these giant explosions can happen multiple times per day.
"Not only are they gigantic. 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," said Glyn Collinson, a space scientist at NASA’s Goddard Space Flight Center in Greenbelt, Md.
When the sun unleashes a large explosion of plasma, or a coronal mass ejection, it shoots out charged particles towards planets, creating space weather. Earth’s magnetosphere, the giant magnetic bubble surrounding the planet, helps to protect us from space weather. However, Venus doesn’t have a chance to protect itself against such weather.
Venus is a barren, inhospitable planet that features an atmosphere so dense it can crush a spacecraft trying to land on its surface within hours. Because Venus has no magnetic protection, it makes it a great experiment for what Earth would look like without its magnetosphere.
Hot flow anomalies are unable to penetrate Earth’s magnetosphere to get down to the surface of the planet, and this releases so much energy just outside that the solar wind can be deflected and forced back towards the sun. However, the situation on Venus is much different than what is seen on Earth.
The only protection Venus has from the solar wind is the charged outer layer of its atmosphere known as the ionosphere. Scientists know that there is a sensitive pressure balance between the ionosphere and the solar wind, which can easily be disrupted by a big coronal mass ejection. The hot flow anomalies on Venus create dramatic, planet-scale disruptions, sucking the ionosphere up and away from the surface of the planet, according to the new study.
The European Space Agency’s (ESA) Venus Express is helping scientists uncover the mysteries of how Venus and its atmosphere interacts with the Sun. In 2010 scientists used the spacecraft to measure an increased rate of ionized particles. This, and other measurements are helping scientists unveil the mysteries behind the second planet from the sun.