It is five times more abundant than everything mankind has ever touched, seen, or tasted — the air we breathe, the ground on which we stand, and the constituents of our bodies. Without it, galaxies would fall apart, and stars would spin off into space.
Mysterious, invisible, and as-of-yet unidentified, dark matter is the universe’s most elusive cosmic phenomenon.
Discovered decades ago when scientists employed NASA’s Hubble Space Telescope to uncover and understand the expansion of the universe, dark matter has since become one of the most fascinating enigmas in the field of physics. Across the world, scientists have been working to illuminate this hidden side of the universe and learn more about the strange substance that inhabits it.
From CERN’s Large Hadron Collider (the world’s most powerful particle accelerator) in Switzerland to the Large Underground Xenon (LUX) experiment being conducted in South Dakota, USA, ambitious projects in several countries are hot on the trail of dark matter. In fact, Japan’s National Astronomical Observatory is already surveying those warps and wobbles to create a first-of-its-kind “dark-matter map” which they aim to complete in 2019.
India too has recently joined the global hunt for the elusive cosmic glue that holds galaxies together. Here’s a brief look at India’s very own subterranean lair for dark matter research.
In 1992, after four decades of conducting pioneering experiments, the 2.3 km-deep research facility at Kolar Gold Field was finally shut down — the mine’s vast network of tunnels had flooded due to disuse (as the gold reserves had dwindled, the mining operations had stopped).
Soon after, India’s particle physicists got together to shape a plan for a new place to study fundamental particles and forces. At the forefront of this effort was Kolkata’s Saha Institute of Nuclear Physics (SINP).
Founded in 1940 as the Institute of Nuclear Physics, the SINP conducts research on theoretical and experimental physics and provides post-graduate training in nuclear, plasma and high-energy physics. It was thanks to the tireless efforts of its scientists that, in September 2017, India finally inaugurated its only underground physics laboratory since KGF’s underground facility shut down in 1992.
Carved out of granite rock at a depth of 555 meters, the lab is basically an abandoned cavern located deep within the innards of a uranium mine that has been refurbished by SINP scientists.
Operated by the Uranium Corporation of India Ltd. (UCIL), this mine is the oldest of six uranium mines in and around Jharkhand’s Jaduguda, a town lies nearly 260 km from Kolkata and 150 km from state capital Ranchi. At a full depth of 905 meters, it is also the second deepest operating underground mine of the country after Hutti gold mine which is more than 1000 metres deep.
As such, the lab’s position within the mine has been carefully selected keeping two important considerations in mind. First, to filter out cosmic rays that interfere with experiments on dark matter, and second, to keep background radiation from uranium to minimal levels — uranium-rich ore is located at least 300 meters away from the cavern.
Set up at a cost of a mere Rs. 20 lakh, the Jaduguda lab is accessible by a lift that takes one into the womb of the earth. Equipped with cutting-edge instruments and detectors designed to look for signatures of cosmic particles, it is expected to help a new generation of Indian physicists gain expertise in working on underground experiments.
Scientists also hope the new lab will play an important role in unravelling the mystery of dark matter. As India’s nuclear chief Dr Sekhar Basu told NDTV,
“Tomorrow, we may know of different types of planets made up of dark matter, different types of life forms… there is enormous potential for enhancing knowledge.”