Ground Report | New Delhi: Geomagnetic Storm to hit Earth; A strong Geomagnetic storm hit Earth on October 30, 2021, after the US Space Weather Prediction Center under the National Oceanic and Atmospheric Administration (NOAA) issued a watch out for a G3 (strong) geomagnetic storm. On October 28, 2021, the Sun blasted a significant solar flare and Coronal Mass Ejection (CME) from sunspot AR2887 AR2887 which is positioned in the center of the Sun and facing the Earth, based on its location wherein the Sun emitted X1 class solar fare.
Geomagnetic Storm to hit Earth
The CME erupted at a speed of 973 km/s and will take 2 days to cross the Sun-Earth divide and reach Earth’s atmosphere by October 30. The US Space Weather Prediction Center (SWPC) continuously observes the Sun. The Solar Dynamics Observatory of the National Aeronautics and Space Administration (NASA) also captured a ‘significant solar flare’ blasting off from the Sun. The US space agency NASA also confirmed that the Sun emitted an X1-class flare on October 29, 2021.
Though the harmful radiation from such a solar flare cannot pass through the atmosphere of Earth but could disrupt some high-frequency radio broadcasts and low-frequency navigation. It may affect GPS signals, satellites, and the electricity grid. The SWPC said that that the X1-class solar flare that erupted from the Sun on October 28 caused a temporary yet strong radio blackout across the sunlit side of the Earth-centered South America.
As per NASA, the X1-class solar flare is expected to hit Earth’s magnetic field on October 30. When the solar storm hits the magnetic field of Earth, it could create an aurora at the North and South poles. The Northern Hemisphere could witness a celestial show known as the Northern Lights. The SWPC Director William Murtagh noted that since the impact of the solar flare will happen during the daylight hours, “we are looking at overnight of the 30th into 31st for the best chance to see the aurora”.
Murtagh also noted that the Sun has five sunspot clusters. These are large magnetic storms that appear darker than the rest of the Sun. Only two of these five clusters are likely to cause any damage to Earth.
The largest storms that result from these conditions are associated with solar Coronal Mass Ejections (CMEs). During a CME, the Sun emits billion tons of plasma. With its embedded magnetic field, the CME arrives at Earth in several days. Some of the most intense solar storms typically arrive in as short as 18 hours. A 5-level NOAA Space Weather Scale classifies Geomagnetic storms on a G-scale.
While the geomagnetic solar storms create beautiful aurora on the poles of Earth, they also can create harmful geomagnetic induced currents (GICs) in the power grid and pipelines and disrupt navigation systems such as the Global Navigation Satellite System (GNSS).
Talking about CMEs, the US Space Weather Prediction Center (SWPC) defines Coronal Mass Ejections (CMEs) as large expulsions of plasma and magnetic field from the Sun’s corona. These CMEs carry billions of tons of coronal material and an embedded magnetic field. The CMEs are found to be traveling from the Sun at speeds between 250 km/s to 3,000 km/s.
Prof Dibyendu Nandi from the Indian Institutes of Science Education and Research explained the scenario as “It is difficult to gauge the full impact. We are expecting to see auroras. The injection of currents in the ionosphere is expected which will, in turn, induce fluctuations in Earth’s magnetic field.”
He added that there are chances of disruptions in navigational networks and global navigation satellite system receivers but “we expect the coronal mass ejection (expulsions of magnetized plasma from the sun’s corona) to have moderate speed so these chances are low.” Prof Nandi is part of the Center of Excellence in Space Sciences India at IISER Kolkata which had predicted this solar flare. The classification system for solar flares uses the letters A, B, C, M, and X.
directly hitting Earth
“It is similar to magnitudes in the Richter scale used to quantify earthquakes. The X-1 class flare has a high magnitude of radiation, but the highest ever observed in the modern era is an X45 flare in 2003 (termed the Halloween storms),” explained Shravan Hanasoge, Associate Professor at the Department of Astronomy and Astrophysics at the Tata Institute of Fundamental Research. The Halloween solar storm led to transformer malfunction and power loss in Sweden and caused multiple satellites to fail.
“We sometimes forget that we live with a star, and the complex phenomena that it exhibits can have a serious impact on our lives. For instance, there was a superstorm in 2012 that narrowly missed directly hitting Earth. Estimates have suggested that if it had hit us, we could have suffered damage of trillions of dollars and taken decades to recover. Although directed towards Earth, the X1 storm of two days ago will have little to no impact on our infrastructure,” Prof. Hanasoge added.
Reports say that the northern lights can be visible to stargazers in some spots in the U.S and far northern parts of the world. The southern lights, which are known as the aurora australis, can also be visible in far southern parts of the world. Impacts from this geomagnetic storm are expected to wane by early next week.