Trivandrum Observatory Study Revisits 1859 Carrington Event

A study based on historical magnetic observations from the Trivandrum Astronomical Observatory has provided new data on the 1859 Carrington Event, a geomagnetic storm of 19th-century solar-terrestrial science. The research was published in Astrophysics and Space Science on 20 September 2026 and was led by R. Jayakrishnan, Head of the Department of Physics and Honorary Director of the observatory.

Carrington Event and Geomagnetic Storms

The Carrington Event occurred in 1859 and is classified among the most intense geomagnetic storms recorded in modern scientific history. Geomagnetic storms are disturbances in Earth’s magnetosphere caused by solar activity, especially coronal mass ejections and solar plasma ejections.

The study places the 1859 event within a sequence of solar eruptions and magnetic disturbances that affected Earth over several weeks. The analysis identifies geomagnetic activity between 14 August 1859 and 15 September 1859, with the strongest phase on 2 September 1859.

Trivandrum Observatory Records

The research used bifilar magnetometer records from the Trivandrum Observatory, a historic observatory in Kerala. These records were preserved in Scotland for more than 160 years after being taken there by John Allan Broun, who served as a former director of the observatory in the 1870s.

The archived observations allowed researchers to reconstruct a multi-phase chronology of the storm. The study records comparable geomagnetic magnitudes for the events of 29 August 1859 and 2 September 1859, with ΔH values of approximately −1851 nT and −1926 nT respectively.

Scientific Context and Space Weather

Space weather refers to conditions in space driven by solar activity that can affect satellites, communication systems, navigation systems, and power infrastructure. Geomagnetic storm studies use historical magnetometer data, solar observations, and magnetic field measurements to reconstruct past solar events.

Anna Szolucha of Jagiellonian University, Poland, supported the rediscovery of the archived records after visiting the observatory in April 2025. The study also refers to an earlier geomagnetic disturbance on 28 August 1859 that preceded the main Carrington phase.

Important Facts for Exams

• The Carrington Event of 1859 is one of the strongest geomagnetic storms recorded in scientific history.
• Bifilar magnetometers measure changes in Earth’s magnetic field and were used in 19th-century observatories.
• The Trivandrum Astronomical Observatory is one of the oldest observatories in India and has historical magnetic records.
• Geomagnetic storms can affect satellites, radio communication, navigation systems, and electric grids.

Historical and Scientific Significance

The Carrington Event is named after British astronomer Richard Carrington, who observed a major solar flare in 1859. Historical magnetic records from observatories remain important sources for studying long-term solar activity and extreme space-weather events.