Synergy Between Atmospheric Studies and Radio Astronomy: Use of Passive Mode Operation of Weather Radar

Abstract

This article explores the application of passive radar techniques for radio astronomy, utilizing the CU-ST Doppler Radar at the University of Calcutta, Kalyani, for celestial observations. Traditional radar systems, designed for atmospheric studies, were adapted to operate in passive mode, enabling the detection of cosmic radio sources without active signal transmission. Observations focused on well-known radio sources, such as Taurus-A (the Crab Nebula) and Virgo-A (a supergiant elliptical galaxy), were conducted to test the radar’s capability in capturing astronomical data. By employing beamforming techniques and processing binary data, significant radio signals were detected, confirming the radar’s ability to observe celestial objects in passive mode. The results demonstrate the radar’s potential as a complementary tool to conventional radio telescopes, offering a novel approach to space weather monitoring and radio astronomical studies. These findings suggest that passive radar can effectively contribute to long-term astronomical research and transient celestial phenomena monitoring without interference from active transmissions. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2026.