The GRAPES-3 experiment is a special telescope-array established in Ooty to detect muons from cosmic ray showers. The experiment has detected a surge in muon intensity correlated with a weakening of the earth’s magnetic field due to a solar storm that hit the earth on June 22, 2015. The results have been published in the journal Physical Review Letters. An Indo-Japanese collaboration, this experiment is unique in that it can be used to study solar storms and space weather at distances up to two times the earth’s radius, unlike satellite-based studies that can yield information only about what is happening in their vicinity.
The muon is an elementary particle similar to the electron, with an electric charge of −1 e and a spin of 1 / 2 , but with a much greater mass. It is classified as a lepton. As is the case with other leptons, the muon is not believed to have any sub-structure—that is, it is not thought to be composed of any simpler particles.
A coronal mass ejection (CME) left the sun on June 21, 2015 and, along with two such others that left the sun on June 18 and 19, reached earth on June 22, 2015. Solar flares are often followed by CMEs which are nothing but giant clouds of plasma which also contain embedded magnetic fields.
This CME was associated with a solar flare from the sunspot region 12371 near the central disc of the sun. This caused a solar storm and ensuing radio blackouts and Aurora Borealis. Analysing data from the GRAPES-3 muon-tracking telecope, scientists have inferred that while it lasted, the CME resulted in weakening the earth’s magnetic field, allowing high energy cosmic rays to burst through.
This method can serve as a monitor of solar storms. Galactic cosmic rays producing a muon burst were bent in the space surrounding the Earth over a volume that is 7 times that of the Earth, and hence they serve as a monitor of the solar storm over this volume. This is in stark contrast to the satellite based measurements that provide only in situ information.
The earth’s atmosphere provides a shield against UV rays and other incident particles. But its protection stretches to less than 100 km around the earth. The stronger protection comes from the earth’s magnetic field which stretches to around 10 times the radius of the earth – about 60,000 km beyond the surface.
This magnetic field deflects most of the galactic cosmic rays – high-energy charged particles that are incident on earth from space. The magnetic field forms the first line of defence against cosmic rays by imposing a threshold energy per unit charge. Only charged particles that have higher energy than this threshold can fall on the earth.
The analysis shows the weakening of the earth’s magnetic field because of the coronal mass ejection.
There is a 32-minute lapse between the muon burst and the arrival of the interplanetary magnetic field. This is because of the time taken for the galactic cosmic rays to diffuse through the magnetised plasma.
Super storms
The largest recorded solar storm in history is the Carrington event of 1859, which disrupted telegraph lines on earth for several hours. This storm caused Aurorae to be recorded even as far south as Florida State in the USA.
If a storm of this magnitude should occur today, it would cripple all the VLSI-based communication systems, smart devices, mobile phones, computer networks and satellites, causing chaos.
Therefore, detecting such muon bursts could serve as an early warning in the case of a superstorm.
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Steve Ovett, the famous British middle-distance athlete, won the 800-metres gold medal at the Moscow Olympics of 1980. Just a few days later, he was about to win a 5,000-metres race at London’s Crystal Palace. Known for his burst of acceleration on the home stretch, he had supreme confidence in his ability to out-sprint rivals. With the final 100 metres remaining,
[wptelegram-join-channel link=”https://t.me/s/upsctree” text=”Join @upsctree on Telegram”]Ovett waved to the crowd and raised a hand in triumph. But he had celebrated a bit too early. At the finishing line, Ireland’s John Treacy edged past Ovett. For those few moments, Ovett had lost his sense of reality and ignored the possibility of a negative event.
This analogy works well for the India story and our policy failures , including during the ongoing covid pandemic. While we have never been as well prepared or had significant successes in terms of growth stability as Ovett did in his illustrious running career, we tend to celebrate too early. Indeed, we have done so many times before.
It is as if we’re convinced that India is destined for greater heights, come what may, and so we never run through the finish line. Do we and our policymakers suffer from a collective optimism bias, which, as the Nobel Prize winner Daniel Kahneman once wrote, “may well be the most significant of the cognitive biases”? The optimism bias arises from mistaken beliefs which form expectations that are better than the reality. It makes us underestimate chances of a negative outcome and ignore warnings repeatedly.
The Indian economy had a dream run for five years from 2003-04 to 2007-08, with an average annual growth rate of around 9%. Many believed that India was on its way to clocking consistent double-digit growth and comparisons with China were rife. It was conveniently overlooked that this output expansion had come mainly came from a few sectors: automobiles, telecom and business services.
Indians were made to believe that we could sprint without high-quality education, healthcare, infrastructure or banking sectors, which form the backbone of any stable economy. The plan was to build them as we went along, but then in the euphoria of short-term success, it got lost.
India’s exports of goods grew from $20 billion in 1990-91 to over $310 billion in 2019-20. Looking at these absolute figures it would seem as if India has arrived on the world stage. However, India’s share of global trade has moved up only marginally. Even now, the country accounts for less than 2% of the world’s goods exports.
More importantly, hidden behind this performance was the role played by one sector that should have never made it to India’s list of exports—refined petroleum. The share of refined petroleum exports in India’s goods exports increased from 1.4% in 1996-97 to over 18% in 2011-12.
An import-intensive sector with low labour intensity, exports of refined petroleum zoomed because of the then policy regime of a retail price ceiling on petroleum products in the domestic market. While we have done well in the export of services, our share is still less than 4% of world exports.
India seemed to emerge from the 2008 global financial crisis relatively unscathed. But, a temporary demand push had played a role in the revival—the incomes of many households, both rural and urban, had shot up. Fiscal stimulus to the rural economy and implementation of the Sixth Pay Commission scales had led to the salaries of around 20% of organized-sector employees jumping up. We celebrated, but once again, neither did we resolve the crisis brewing elsewhere in India’s banking sector, nor did we improve our capacity for healthcare or quality education.
Employment saw little economy-wide growth in our boom years. Manufacturing jobs, if anything, shrank. But we continued to celebrate. Youth flocked to low-productivity service-sector jobs, such as those in hotels and restaurants, security and other services. The dependence on such jobs on one hand and high-skilled services on the other was bound to make Indian society more unequal.
And then, there is agriculture, an elephant in the room. If and when farm-sector reforms get implemented, celebrations would once again be premature. The vast majority of India’s farmers have small plots of land, and though these farms are at least as productive as larger ones, net absolute incomes from small plots can only be meagre.
A further rise in farm productivity and consequent increase in supply, if not matched by a demand rise, especially with access to export markets, would result in downward pressure on market prices for farm produce and a further decline in the net incomes of small farmers.
We should learn from what John Treacy did right. He didn’t give up, and pushed for the finish line like it was his only chance at winning. Treacy had years of long-distance practice. The same goes for our economy. A long grind is required to build up its base before we can win and celebrate. And Ovett did not blame anyone for his loss. We play the blame game. Everyone else, right from China and the US to ‘greedy corporates’, seems to be responsible for our failures.
We have lowered absolute poverty levels and had technology-based successes like Aadhaar and digital access to public services. But there are no short cuts to good quality and adequate healthcare and education services. We must remain optimistic but stay firmly away from the optimism bias.
In the end, it is not about how we start, but how we finish. The disastrous second wave of covid and our inability to manage it is a ghastly reminder of this fact.