About

• The Kodaikanal Solar Observatory (KoSO), established in 1899 and owned by the Indian Institute of Astrophysics, is one of India's most significant scientific institutions for solar studies.
• Located near Kodaikanal in Tamil Nadu, its mission originated from the need to understand the link between solar activity and the Indian monsoon, especially after a severe famine in the 1890s.

• The Evershed effect (radial flow of gas in sunspots) was first discovered here in 1909.​
• Pioneered systematic, daily solar observations (notably in Ca II K wavelength since 1904), capturing chromospheric activity and solar magnetism over a century.​
• Equipped with high-powered telescopes, solar tower, spectroheliographs, a solar tunnel telescope, and archival photographic plates.​

Current Research and Applications

• Researchers have reconstructed the Sun's polar magnetic field spanning the last 100 years using KoSO's archive, greatly improving accuracy in predicting solar storms and understanding space weather.​
• KoSO's digitized historical data is now a critical global resource for AI and machine learning studies in solar physics.​
• KoSO regularly conducts ionospheric and geomagnetic observations. Data is shared with the India Meteorological Department and World Meteorological Organization for global weather and climate studies.​

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