Indian astronomers discovered 34 new giant radio sources (GRSs) utilising the Tata Institute of Fundamental Research’s Giant Metrewave Radio Telescope (GMRT). This major discovery, from the TIFR GMRT Sky Survey Alternative Data Release 1 (TGSS ADR1) at 150 MHz, includes some of the most distant GRSs known and calls into question current beliefs regarding the conditions in which GRSs develop.
The GMRT, located in Khodad village, approximately 90 km north of Pune, is a cutting-edge facility managed by TIFR’s National Centre for Radio Astrophysics. From 2010 to 2012, the GMRT conducted a 150 MHz sky survey, spanning 90% of the sky, resulting in discoveries such as these 34 new GRSs.
GRSs are among the universe’s largest structures, spanning millions of light years and fuelled by supermassive black holes at their cores. They emit jets of hot plasma, forming huge radio lobes. Detecting GRSs is difficult due to their large size and weak emissions, however low-frequency surveys such as TGSS help overcome these challenges.
Two GRSs, J0843+0513 and J1138+4540, call into question the idea that GRSs exclusively occur in low-density environments, implying that other factors influence their formation. The study team, including PhD students Netai Bhukta and Souvik Manik, aims to conduct additional investigations to better understand these cosmic giants’ formation and evolution.
