In the context of modern scientific research, consider the following statements about ‘IceCube’, a particle detector located at South Pole, which was recently in the news: 1) It is the world’s largest neutrino detector, encompassing a cubic kilometre of ice. 2) It is a powerful telescope to search for dark matter 3) It is buried deep in the ice. Which of the statements given above is/are correct?

All three statements are correct, so the answer is D. IceCube is built into roughly one cubic kilometre of clear Antarctic ice at the South Pole. It is the world's largest neutrino detector, and it detects the faint blue Cherenkov light produced when a neutrino interacts in the ice and creates a charged particle. This is statement 1.

Statement 2 is correct too. Neutrinos are used as cosmic messengers, and IceCube searches for neutrinos produced when hypothetical dark matter particles (WIMPs) annihilate, for example in the Sun or the galactic centre. It is an indirect dark matter search.

Statement 3 is correct as well. The sensor strings are lowered into holes drilled between about 1,450 m and 2,450 m below the surface. The ice acts as both the detection medium and a shield against cosmic-ray muons.

The core concept is neutrino astronomy, where Cherenkov detection makes big-volume natural media useful. For Mains GS-III (Science and Technology), it fits frontier research and big science, and it also links to India's Antarctic research presence under the Antarctic Treaty system.

Trap: Many aspirants reject statement 2 because they associate dark matter detectors only with deep underground xenon labs. IceCube's indirect search is still a valid dark matter programme.