Are the Earth’s Magnetic Poles About to Flip?
Three European satellites launched Friday on a mission to study why the magnetic field surrounding Earth appears to be weakening.
The four-year study will collect data and map the field, which protects the planet (and us) from solar radiation.
Scientists say the field’s strength has weakened by about 15 percent in the last 200 years.
The weakening could be a sign of “polarity reversal" - when the field flips end-to-end, turning north into south. The phenomenon occurs every 200,000 to 300,000 years. But the last time the field flipped was almost 800,000 years ago.
The magnetic field is believed to be generated by the Earth’s molten iron core. The field reaches thousands of miles into space and creates a bubble around the earth. It’s what makes compasses work, and aids everything from navigation systems to animal migrations…
Read more:
http://philadelphia.cbslocal.com/2013/11/25/space-agency-weakening-of-earths-magnetic-field-could-indicate-pole-reversal/
Story via Megan Thompson
image: ESA/ATG MediaLab
Some say that the number of monarca butterflies coming to Michoacan, México is lower this year. Could this be why?
ReplyDeleteMathieu Hautefeuille some say we gonna see frogs levitate in the magnetic field so perhaps that's why your precious butterflies coming to Mexico could be lower this year =)
ReplyDeleteIf the last time polarity flip happened was 800,000 years ago... Why do we think it happens every 2-300,000 years? I don't quite understand the logic behind that particular deduction.
ReplyDeleteEarth has settled into a pattern of switching magnetic poles about every 200,000 to 300,000 years… with a period of twice that long since our last reversal.
ReplyDeleteThe last time that Earth’s poles flipped in a major reversal was about 780,000 years ago, in what scientists call the Brunhes-Matuyama reversal. The fossil record shows no drastic changes in plant or animal life, at least this is what NASA people say.
Read more here ..when you have time =)
http://www.es.ucsc.edu/~pkoch/EART_206/09-0303/Supplemental/Bassinot%20et%2094%20EPSL%20126-91.pdf
Corina Marinescu thank you.
ReplyDelete