Thursday, December 28, 2017

Minor Geomagnetic Storm May Hit Earth on New Year’s Day

Credit: NASA

A G1-class (minor) geomagnetic storm may hit our planet on Monday, January 1, according to National Oceanic and Atmospheric Administration (NOAA). This is due to a stream of solar wind expected to strike Earth's magnetic field on that day.

As a result of the possible minor geomagnetic storm, auroras could be visible around Earth's poles and weak power grid fluctuations could occur. Such storm could also have minor impact on satellite operations.

Geomagnetic storms can increase the density and distribution of density in the upper atmosphere, causing extra drag on satellites in low-earth orbit. The local heating also creates strong horizontal variations in the in the ionospheric density that can modify the path of radio signals and create errors in the positioning information provided by GPS. While the storms create beautiful aurora, they also can disrupt navigation systems such as the Global Navigation Satellite System (GNSS) and create harmful geomagnetic induced currents in the power grid and pipelines.

NOAA reveals that solar activity is expected to stay generally at very low levels until at least January 20. One more minor geomagnetic storm may occur on January 13 due to recurrent coronal hole high speed streams (CH HSSs).

Fast CH HSSs can impact Earth’s magnetosphere enough to cause periods of geomagnetic storming to the G1-G2 levels; although rarer cases of stronger storming may also occur. The larger and more expansive coronal holes can often be a source for high solar wind speeds that buffet Earth for many days.