Since the establishment of the first magnetic observatory in Gottingen, Germany `by Carl Friedrich Gauss in 1832, establishment of a network of observatories spread over Europe, Canada, South Africa, Australia, India, Singapore, Russia, China recording measurements 5 minute intervals. By 1841 a world wide network of 53 observatories was operational, which grew over the next century. These observatories record the variations of the geomagnetic field and the absolute values of the inclination and declination at each location to form the database for the study of changes in the Earth’s core, ionosphere, magnetosphere. The magnetic observatory (HYB) of NGRI was commissioned in 1964, just three years after the establishment of the Institute. As part of the global INTERMAGNET observatory network, it provides 1 minute and 1 second three component variation data (near real time) as well as absolute baselines (annually). Another Observatory has been established at Choutuppal campus 65 km away to study special phenomena. Additional observation sites have been set up in Kanyakumari, Lakshadweep and Andaman-Nicobar for the dual purposes of studying induction responses and equatorial ionospheric phenomena.

The Observatories produce high precession Vector and Absolute Scalar magnetometers for recording the geomagnetic field variations with 0.001 to 0.01 nT and real-time data transmission to global scientific community and is an archiver of historical (over 50 years) of 3-component variation and baseline records, K-indices, principal magnetic storms and short-period events of the geomagnetic field and more than 30 years of ultra-low frequency magnetic and earth current records in equatorial region over several decades. Calibration facility for Declination-Inclination and Proton Precession Magnetometers. Research on ionospheric variability at Equatorial latitudes, pulsation patterns from ground and satellite and induction studies in Andaman-Nicobar have recently been conducted.