Thread: Memory Lane (In my own language)

King Rama IV (1851 – 1868) invited foreign astronomers and important guests to the village of Wa Koh, near the southern port of Prachuap Khiri Khan Province to witness the solar eclipse on 18 August 1868.

The King had determined through astronomical calculations that Ban Wa Koh (the colorized B&W photo courtesy of ‘Page Siam Colorization by Noomrattana’ taken on that day) would be the best site for scientific observations of the event. In order to prepare the event, steamships ferried workers and supplies were carried from Bangkok to build an observatory and residences for hundreds of guests and dignitaries, including almost the entire Thai court, senior French and British diplomats, and a French-led astronomical team.

The King had studied European astronomy and mathematics alongside the traditional Siamese astronomy, used to fix the dates of religious ceremonies, which was based on astronomical texts from India and the Bagan Kingdom of Myanmar.

After taking the throne, the King criticized his court astronomers as old-fashioned and inaccurate, and set about to reform the calendar with the help of scientific astronomy. His predication of the exact timing of the eclipse would be proof of his efforts to reform the Siamese calendar and astronomy and his rebuke to his court astronomers.

According to a report from a French diplomat who was present, the King proudly reported that the French astronomers had confirmed that his predictions were of greater accuracy than their own, says historian Thongchai Winichakul in his book "Siam Mapped". But for the King, this first solar eclipse would also be his last; like many who journeyed to Wa Koh with the King, had caught malaria. The King died in Bangkok a few weeks later.

The date of the 1868 eclipse - 18August - is celebrated as National Science Day in Thailand, and Wa Koh is now a national park and the site of an observatory involved in astronomy public outreach.