Right Time, Right Place: Earth’s Magnetic PolesIf you were to list factors crucial to life on

Right Time, Right Place: Earth’s Magnetic PolesIf you were to list factors crucial to life on Earth—water, oxygen, appropriate temperature—magnetism might not make the list. But it should, because without Earth’s magnetic poles, we probably wouldn’t be here. Magnetic poles may be one of the most important things we never think about it.Let’s meet the two major players in this unique scenario: Earth’s magnetic field and solar winds.Earth’s magnetic field presents a bit of a mystery at times, but we know its origin has something to do with the iron core. Since the outer core is liquid iron cooling by losing heat, it convects. Convecting, superheated iron under the right conditions can generate a geodynamo —or in simpler words, generate a magnetic field. This magnetic field can be detected anywhere on the planet—thus why a compass points North.Solar winds are not wind in the typical weather sense; they are beams of ions that stream from the sun. Despite the sun’s immensity, its gravity cannot hold on to some of its more highly charged particles. These particles make their way outwards, sometimes at velocities as fast 500 miles per second.What happens when the solar winds encounter our magnetic field? Since the winds are made up of charged particles, they get deflected. The magnetic field creates sort of a safety blanket around Earth (called the magnetosphere) that effectively reroutes the sun’s zippy ions.What would happen if the magnetic field wasn’t there? Again we can look to our planetary neighbors for possible answers. Mars does not have a magnetic field. It also doesn’t have a life-supporting atmosphere. Coincidence? We think not. Many astronomers believe that Mars used to have magnetic poles, but when its core cooled off, the magnetosphere disappeared, along with the atmosphere and any surface water that may have existed.Solar winds would most likely strip the Earth of its atmosphere if the magnetosphere wasn’t blanketing our beloved planet. In 2008, Mars, Earth, and the sun all happened to fortuitously line up, making it an ideal time for a study regarding solar winds and atmospheres. Research found that Mars lost significantly more oxygen due to solar winds than Earth did, thus making us all a little more grateful for those poles (find the study here–http://bit.ly/1SDNBiU).There is, however, a possibility that the story isn’t that simple. Venus doesn’t have magnetic poles, either, yet it’s got the thickest atmosphere in the solar system. There is some research, however, that suggests it’s got some sort of induced magnetic field in its upper atmosphere (more about that here—http://bit.ly/1g1VbCn).Although the connection between magnetosphere, ionosphere, atmosphere and all the other “-spheres” may not be entirely understood, Earth’s magnetic poles appear to be another one of those unique little details that keep us calling it home.-CMPhoto (a model of Earth’s magnetic field lines) credit: Dr. Gary A. Glatzmaier http://bit.ly/1Ma18LoFor more information: http://bit.ly/1IBswuK -- source link

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