Phys.org October 30, 2023 Both solar wind and ionospheric sources contribute to the magnetotail plasma sheet, but how their contribution changes during a geomagnetic storm is an open question. The source is critical because the plasma sheet properties control the enhancement and decay rate of the ring current, the main cause of the geomagnetic field perturbations that define a geomagnetic storm. An international team of researchers (USA – University of New Hampshire, Lockheed Martin Advanced Technology Center, Harvard-Smithsonian Center for Astrophysics, Japan) used the solar wind composition to track the source and showed that the plasma sheet source changed from […]
Tag Archives: Geomagnetism
Scientists in Japan Just Found a Detailed Record of Earth’s Last Magnetic Switcharoo
Science Alert October 31, 2020 Every 200,000 to 300,000 years, Earth’s magnetic poles reverse. The last reversal was unusual because for some reason, the poles have remained oriented the way they are now for about three-quarters of a million years. Researchers in Japan collected new samples and conducted paleo- and rock-magnetic analyses of samples from the Chiba composite section which is considered to contain the most detailed marine sedimentary record of the Matuyama-Brunhes geomagnetic reversal. It provides the most reliable chronostratigraphic framework of the time period around the Brunhes-Matuyama reversal. According to their study it took about 20,000 years, including […]