India is just days away from embarking on a historic journey into solar exploration with the Aditya-L1 mission. This mission is set to boost our understanding of solar activity and its effects on our planet. This mission is expected to launch in early 2024. It comes at an important time, as scientists are increasingly recognizing the potentially devastating threats that solar storms can pose to our planet’s technological infrastructure.
The Aditya-L1 spacecraft will be equipped with seven scientific instruments. Among them is the Visible Emission Line Coronagraph (Velc), for which the Principal Investigator is Prof. Ramesh from Indian Institute of Astrophysics (IIA). Velc will read and interpret the data on solar storms. This will offer unprecedented, critical insight into the Sun’s corona, where all solar activity begins. This knowledge is critical for preventing and minimizing the impacts of solar events before they happen.
Historically, solar storms have had devastating consequences. One of the most notable instances, the Carrington Event of 1859, was the largest solar storm ever documented. In that it knocked out all global telegraph lines, demonstrating just how devastating an effect solar activity can have on our technological world. One such solar storm in November 2015 triggered serious disruptions to air traffic control over Sweden and other European airports. This event brought to our attention the very real threats that solar storms represent to our sleek and sophisticated infrastructure.
On September 13, 2024, a notable coronal mass ejection (CME) occurred at 00:30 GMT, with its origin temperature reaching a staggering 1.8 million degrees Celsius. This CME released a huge storm of creative energy. That was the equivalent of 2.2 million megatons of TNT—much more than the atomic bombs we dropped on Hiroshima and Nagasaki, which measured 15 and 21 kilotons, respectively. Such immense energy can lead to geomagnetic storms that disrupt weather patterns in near space, where around 11,000 satellites operate.
Prof Ramesh emphasized the significance of this research, stating that “the learnings from this will help us work out the countermeasures to be adopted to protect satellites in near space. They will help us gain a better understanding of near-Earth space.”
CMEs are an especially acute danger to satellites and power grids. In February 2022, a CME resulted in the loss of 38 commercial satellites, while a 1989 event knocked out part of Quebec’s power grid, leaving six million residents without electricity for nine hours. According to Prof Ramesh, “They can make all the electronics on a satellite malfunction, knock down power grids and affect weather and communication satellites.”
The Aditya-L1 mission will be the fulcrum of monitoring and observation of these phenomena. Prof Ramesh further explained that when the Sun is in regular mode, there are two to three CMEs coming out every day. As we approach the next maximum activity cycle, with potential CMEs possessing energy contents reaching up to 100 million megatons, understanding these events becomes increasingly important.
“I consider the CME we evaluated to have occurred when the Sun was in the normal activity phase. Now this sets the benchmark that we’ll be using to evaluate what is in store when the maximum activity cycle occurs,” – Prof Ramesh.
His successor, Aditya-L1’s Velc, has been designed to ensure continuous observations of solar activity. Prof Ramesh described its capabilities: “Aditya-L1’s coronagraph is the exact size that lets it nearly mimic the Moon, fully covering the Sun’s photosphere and allowing it an uninterrupted view of almost all of the corona 24 hours a day, 365 days a year, even during eclipses and occultations.”
The mission’s primary objective is to improve our understanding of how the Sun operates. Its goals fit into a larger framework of scientific initiatives studying the Sun’s effect on Earth. Solar activity has incredible impacts not just on our technology, but increasingly on our climate and weather.
As researchers prepare for Aditya-L1 to launch, they anticipate significant discoveries in solar science. These major improvements will be fundamental to the international community’s efforts to protect technology and wires from solar storms.