All articles tagged with #geomagnetic field
Satellites have revealed that the South Atlantic Anomaly, a significant weakening in Earth's magnetic field, is expanding and becoming more complex, likely due to internal and external geophysical processes, which could impact navigation, satellite safety, and radiation exposure.
Scientists analyzing data from NASA's GRACE satellites discovered evidence of a massive shift deep within the Earth's interior near the core-mantle boundary, possibly caused by changes in mantle minerals like perovskite, which may have influenced Earth's magnetic field and caused a geomagnetic jerk around 2007. They plan to use data from the follow-up GRACE-FO mission to further investigate these deep Earth processes.
NASA warns of the growing South Atlantic Anomaly, a magnetic weakness over South America and the Atlantic Ocean caused by deep Earth processes, which poses risks to satellites and space technology. The anomaly is expanding and splitting into two lobes, complicating predictions and increasing danger for space missions, but it is not an indicator of an imminent magnetic pole reversal.
Scientists present new findings on the Laschamps excursion, a period 41,000 years ago when Earth's magnetic field weakened, allowing harmful cosmic rays to bombard the planet. By measuring cosmogenic radionuclides in ice and marine sediment cores, researchers found that the production rate of beryllium-10 was two times higher than present-day levels during this period, indicating very low magnetic field intensity and increased cosmic ray exposure. These findings are important for understanding past extreme events, predicting space climate, and assessing their potential effects on the environment and Earth's system.
Scientists have discovered a planet-sized solid metal ball at the Earth's center, located within the inner core and made of iron-nickel alloy. This distinct fifth layer of the Earth is approximately 400 miles wide and plays a crucial role in generating the planet's geomagnetic field, which shields Earth from cosmic rays and is essential for sustaining life. The discovery, documented by seismologists at the Australian National University, suggests that the innermost core has a different crystal structure than the surrounding core, and its existence could provide insights into how life can survive on Earth and other planets.
Seismic waves passing through the Earth's inner core have revealed that it is textured rather than homogenous. This discovery provides valuable insights into the age, composition, and structure of the inner core, which plays a crucial role in maintaining the planet's geomagnetic field. By analyzing echoes of powerful earthquakes, researchers have found that the inner core exhibits inhomogeneity on a scale of "grains" smaller than 10 kilometers. The texture becomes stronger towards the center of the Earth, suggesting rapid growth during its formation. The study sheds light on the complex nature of Earth's inner core and its significance in understanding the planet's dynamics.
Researchers from the Institute of Geochemistry of the Chinese Academy of Sciences have found that Earth's anisotropic inner core structure is driven by the dipole geomagnetic field. The alignment of the Fe-H lattice could be driven by an electric field, which explains the anisotropic seismic velocities in the inner core. The study provides a new perspective to understand the mysteries of the Earth's inner core and Earth's magnetic field.