Welcome to the Kodaikanal Solar Observatory Digitized Data Archive!

Kodaikanal Solar Observatory

The Kodaikanal Observatory of the Indian Institute of Astrophysics is located in the beautiful Palani range of hills in Southern India. It was established in 1899. Solar observations at this observatory over the last 100+ years provide one of the longest continuous series of solar data. Apart from that, simultaneous observations in different wavelengths make this data a unique one and suitable for multi-wavelength studies.

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Data policy: If you use the digitized data in any publications, please refer to these papers and include an acknowledgement to the service:

  1. Kodaikanal Digitized White-light Data Archive (1921-2011): Analysis of various solar cycle features
    Sudip Mandal, Manjunath Hegde, Tanmoy Samanta, Gopal Hazra, Dipankar Banerjee, B Ravindra A&A 2017

  2. Digitized archive of the Kodaikanal images: Representative results of solar cycle variation from sunspot area determination
    Ravindra, B.; Priya, T. G.; Amareswari, K.; Priyal, M.; Nazia, A. A.; Banerjee, D., 2013A&A...550A..19R


Kodaikanal solar observatory is a facility of Indian Institute of Astrophysics, Bangalore, India. This data is now available for public use at http://kso.iiap.res.in through a service developed at IUCAA under the Data Driven Initiatives project funded by the National Knowledge Network.

Note: This site replaces the older site currently available from this link. The present site does not include listings for data obtained from the Twin Telescopes - refer to the old site if you need access to this data.