“One of the oldest modern observatories was first set up in Madras by William Petrie. Known as the Madras Observatory, it was what gave birth to the Kodaikanal Solar Observatory (KSO) which has been collecting images of the sun for over a hundred years,” said professor Siraj Hasan, former director of Indian Institute of Astrophysics, Bengaluru.
He was speaking at the inaugural function of the symposium of the International Astronomical Union in Jaipur on Monday. There are other observatories, such as the ones at Mount Wilson Observatory and Kitt Peak, where similar long-term data sets have been collected, and the theme of the symposium is to work towards eliminating discrepancies across various such sets. The symposium was inaugurated by Ajit Khembavi, chairperson of the governing council of Indian Institute of astrophysics (IIAP).
Cross-calibration
Referring to an earlier conference, Dipankar Banerjee of IIAP, the host institute, said, “We are in the early days of this cross-calibration of various data sets. The Kodaikanal image set is special because it not only has long term data, but there are three different types of images that overlap with other data sets.”
The digitisation of the images from KSO has been happening since 2006. The raw data has been available for the general public. Now the team, including members of IIAP, have processed it and made it searchable at three levels.
Professor Hasan further said that two major initiatives were on the horizon. He was referring to the Aditya-L1 solar physics space mission and the National Large Solar Telescope project at Merak in Jammu and Kashmir. The symposium witnessed the gathering together of nearly 250 participants from across the world.
A satellite meeting organised by CESSI, Kolkata, on February 18, commemorated the contributions made by astrophysicist Arnab Rai Choudhuri.
