5 ms·
Earth's magnetic pole has been known to switch sides in the past. https://en.wikipedia.org/wiki/Geomagnetic_reversal https://en.wikipedia.org/wiki/Geomagnetic_r
by feniv 8y ago
Earth's magnetic pole has been known to switch sides in the past. https://en.wikipedia.org/wiki/Geomagnetic_reversal https://en.wikipedia.org/wiki/Geomagnetic_reversal
"183 reversals over the last 83 million years... A brief complete reversal, known as the Laschamp event, occurred only 41,000 years ago during the last glacial period. ... Geologists first noticed that some volcanic rocks were magnetized opposite to the direction of the local Earth's field.".
- darkerside 8y agoWhen this happens, does the magnetism "rotate" around the Earth, or does it fade out and fade back in reversed?
- idbehold 8y agoCloser to fading out and back in.
- michaelg7x 8y agoDoes this mean anything for the protection the planet receives from cosmic rays or solar wind?
- AndrewDucker 8y agoDefinitely https://m.phys.org/news/2012-11-cosmic-rays-reveal-event-earth.html https://m.phys.org/news/2012-11-cosmic-rays-reveal-event-ear...
- deleted 8y ago[deleted]
- techas 8y agoIndeed. Some people believe these “unshielded” periods might had some influence on the evolution of the species. Without those, the rate of change is just not enough to get to humans...
- DoctorOetker 8y agoI'm not contesting but merely interested in references.
- feniv 8y agoHere's a gif from a 1995 supercomputer simulation of the reversal process - https://imgur.com/a/jgpZZBF https://imgur.com/a/jgpZZBF "The tubes represent magnetic field lines, blue when the field points towards the center and yellow when away." Original source: https://www.psc.edu/science/glatzmaier.html https://www.psc.edu/science/glatzmaier.html It took them a year of computing on a CRAY C90 and 2000 hours of processing.
- deleted 8y ago[deleted]