New research has suggested that magnetospheres assume a vital role in shielding planets from even small solar emissions, which can bring about critical damages to a planet.
The interchange between the Earth and sun is vital for making the planet habitable, and harmony between a planet that can shield itself from the harshest solar emissions and the sun that gives out reusable energy. The sun consistently emits energy, light and a consistent stream of particles, called solar wind, that bathes the planets as it goes out into space.
Coronal Mass Ejections (CMEs), massive bursts of gas and magnetic fields from the sun, happen as well, disturbing the air around a planet. On Earth, a percentage of the effect of these CMEs is diverted by a natural magnetic bubble known as a magnetosphere.
Bad news for some planets, like Venus, is that the planet does not have any defensive magnetosphere. On Dec. 19, 2006, the sun shot out a little, slow-moving puff of solar material. After four days, this drowsy CME was nevertheless strong enough to tear away sensational amounts of oxygen out of Venus' atmosphere and send it out into space, where it was forever lost.
Learning exactly why a minor CME has such a powerful impact may have significant consequences for comprehending what makes a planet hospitable for life.
Venus is an especially inhospitable planet; it is 10 times more humid than the Earth with an atmosphere so deep that the longest time any space shuttle has endured on its surface before being destroyed, is a little more than two hours. Perhaps such vulnerabilities to the sun's storms added to this environment.
Regardless, understanding precisely what impact the absence of a magnetosphere has on a planet such as Venus could help us understand more about the habitability of the different planets discovered outside our solar system.
The group narrowed three potential outcomes for the mechanism that forces oxygen into space. First, even a slight CME can expand the solar wind's pressure, which may disturb the typical flow of the atmosphere around the planet from front to back, thus releasing oxygen out into space. Second, the magnetic fields moving with the CME can alter the magnetic fields that are ordinarily induced around Venus by the solar wind to an arrangement that can bring about atmospheric outflow. The last possibility is that the waves within Venus's bowshock may take away particles as they move.
The study was published in the Journal of Geophysical Research.
Photo: NASA Goddard Space Flight Center | Flickr