Earth on Alert for G2 Geomagnetic Storm

Artist's depiction of an active sun that has released a coronal mass ejection or CME. CMEs are magnetically generated solar phenomenon that can send billions of tons of solar particles, or plasma, into space that can reach Earth one to three days later and affect electronic systems in satellites and on the ground. Credit: NASA — Artist’s depiction of an active sun that has released a coronal mass ejection or CME. CMEs are magnetically generated solar phenomenon that can send billions of tons of solar particles, or plasma, into space that can reach Earth one to three days later and affect electronic systems in satellites and on the ground. Credit: NASA

The National Weather Service’s Space Weather Prediction Center (SWPC) is warning that a G2 class Geomagnetic Storm could impact Earth on Thursday, perhaps impacting electrical grids and transformers, interfering with satellites, disrupting radio communications, and sending the Northern Lights much more south than usual. In their latest bulletin, the SWPC believes there’s a chance of G1 Geomagnetic Storm Conditions on Earth tomorrow, growing to a G2 Geomagnetic Storm event for Thursday.

Several explosive events have occured on the Sun in recent days, with each sending different kinds of blasts towards Earth. In the last 48 hours, the aurora has been spotted in southern Alaska and across New York, Vermont, New Hampshire and Maine.

Based on observations from NASA's Solar Terrestrial Relations Observatory, also known as STEREO, show that the CME left the sun days ago. Image: NASA — A CME Filament Eruption occurred; one was captured here during another solar event by NASA’s Solar Terrestrial Relations Observatory, also known as STEREO. Image: NASA

According to the SWPC, minor enhancement in the solar wind is likely tonight as the August 26 coronal mass ejection (CME) passes near Earth. Solar wind parameters are expected to once again become enhanced on September 1-2 Sep due to the anticipated arrival of the August 28 CME combined with an additional CME from a filament that disappeared from near the center meridian on August 28.

Geomagnetic storms are rated on a 1-5 scale, with 1 being the weakest and 5 having the most potential for damage. Even a G1 geomagnetic storm could create issues: there could be weak power grid fluctuations and minor impacts on satellite operations. Aurora, also known as the “Northern Lights”, could be visible at high latitudes from northern Michigan and Maine to points north. Impacts and aurora change as the geomagnetic storm scale increase.

Chart showing NOAA Space Weather Scales for Geomagnetic Storms. Image: NOAA

Dark regions on the Sun known as coronal holes are one of the main drivers of space weather now. According to the Space Weather Prediction Center, coronal holes appear as dark regions on the Sun because they are cooler than the surrounding plasma and are open magnetic field lines. The Sun’s outermost part of its atmosphere, which is known as the corona, is where these dark regions appear. The solar corona was also one of the main features of the Sun scientists were most excited to study during the past solar eclipse. You are able to notice these features in extreme ultraviolet (EUV) and soft x-ray solar images.

Solar wind is always flowing from the Sun and towards Earth but coronal holes are known for releasing enhanced solar wind. Coronal holes can develop anywhere on the sun and are more common during solar minimum. One solar rotation of the Sun occurs every 27 days and coronal holes are sometimes able to last several of these. It is common to see persistent coronal holes at the north and south pole of the…