The sun illuminates the countries of high latitudes in a “Solar Deepavali”
Scientists from CESSI, IISER, Kolkata, accurately predicted the event using locally developed models and data from NASA observatories
A solar flare that occurred on the Sun triggered a magnetic storm that scientists at the India Center of Excellence for Space Science (CESSI), Indian Institutes of Science Education and Research (IISER), Kolkata , had predicted to arrive on Earth in the early hours of November 4.
They had said that the magnitude of this storm would be such that it would trigger spectacular auroras (the colorful bands of light seen at the North and South Poles) in the polar regions and high latitudes, just in time for the Deepavali celebrations in India.
This prediction, which was based on models built by them and data from NASA observatories, is confirmed and several countries in the northern hemisphere will see auroras.
Judging by near-real-time data from NASA’s Deep Space Climate Observatory (DSCOVR) satellite, scientists have observed a sharp jump in transverse magnetic fields, density, and plasma wind speeds which are telltale signatures. of the arrival of a CME shock front, according to Dibyendu Nandi of CESSI, Kolkata, whose team predicted the event.
“It happened at 1:00 am IST. We will know if it is the coronal mass ejection flow according to its evolution during its passage. These observations are made at Lagrange Point L1, ”he said in a message to The Hindu.
The solar magnetic cycle that works deep inside the Sun creates regions that rise to the surface and appear as dark spots. These are the sunspots. Solar flares are highly energetic phenomena that occur inside sunspots. In a solar flare, the energy stored in the magnetic structures of the sun is converted into light and heat energy. This causes the emission of high energy x-rays and highly accelerated charged particles that leave the surface of the sun.
Sometimes solar flares also cause hot plasma to be ejected from the Sun, causing a solar storm, and this is called coronal mass ejections (CME). The CME can harbor energies exceeding that of a billion atomic bombs.
The energy, radiation, and high-energy particles emitted by flares can affect Earth-bound objects and life on Earth – it can affect satellite electronics and affect astronauts.
Very powerful Earth-directed coronal mass ejections can cause power grids to fail and affect oil pipelines and submarine cables. They can also cause spectacular auroras in high latitude and polar countries.
The last time a major blackout due to coronal mass ejection was recorded was in 1989 – a powerful geomagnetic storm that destroyed North America’s power grid, plunging large parts of Canada into darkness and triggering spectacular auroras beyond the polar regions.
The prediction process takes place in two stages: First, the group analyzes the possibility of a strong solar flare from an active region – i.e. sunspot clusters – using of a machine learning algorithm developed at CESSI.
“This algorithm needs observations of the magnetic fields of the sunspots, from which we extract various parameters to train the algorithm. For this we use data from the NASA Solar Dynamics Observatory, in particular the helioseismic and magnetic imaging instrument, ”said Dibyendu Nandi, who, together with his doctoral student Suvadip Sinha, developed the algorithm.
The second step is to estimate the arrival time of the coronal mass ejections and to predict the geomagnetic storm. The group uses the near-Sun evolution of coronal mass ejections via the European Space Agency’s SOHO satellite and NASA’s STEREO satellite to extract their velocity.
There is an associated eruption, and its position on the Sun is used to extract the original location of the CME. The CME source location and speed are used as inputs by the group into a publicly available model widely referred to as the Drag-Based Ensemble Model to calculate CME arrival times and speed.
“This last step involves uncertainties because the physics of the propagation of CMEs is quite complex, but treated in a simplified way in this model”, explained Professor Nandi. “When ISRO’s Aditya-L1 satellite is launched, we will receive similar solar storm data from this observatory,” he added.
Professor Nandi added: “Reports are already coming in indicating that we have hit the nail on the head with the prediction. The storm arrived less than an hour after our forecast time with speeds similar to what we had estimated. Auroras are reported in unexpected countries such as Scotland, Ireland and states of the United States, except in high latitude areas. Now, the NOAA Space Weather Prediction Center had upgraded the information on the geomagnetic storm resulting from the impact of the CME to be dangerous. “