Gerhana Mata Hari

Tuesday 20th September, 2016


Our speaker was Mike Frost from Coventry and Warwickshire Astronomical Society and he came to tell us about "Gerhana Mata Hari". This was perhaps one of the most unusual titles that a speaker had chosen but it all became clear when he explained that this was a Malay phrase that meant solar eclipse and he had travelled to Indonesia to witness this spectacular event.

The total solar eclipse in March this year was only one of many that he had been lucky enough to witness but he said that this time he was able to enjoy the event wearing a T-shirt. The last one he had witnessed was in freezing conditions in March last year in Svalbard where layers of thermal clothing were essential to his survival as temperatures were below -22° C.

Mike said that he flew first to Jakarta, which is the capital of the Republic of Indonesia and the most populous city of the Indonesia archipelago. From there it was a short hop by another plane to Manado, situated in the Province of North Sulawesi. While in the area he was able to visit various tourist attractions such as volcanoes, wildlife reserves, markets and even see the world's largest flying statue of Jesus.

On the day of the eclipse he travelled to one of the Spice Islands, Tidore, where he would eventually witness the total solar eclipse from the beach where temperatures were 55 degrees warmer than those he had experienced in Svalbard. He had checked the general weather forecast which did not look very promising as it reported overcast skies but the astronomical forecast was more hopeful saying the cloud may be patchy. In the end, for the short time that the Moon totally moved across the Sun to produce a total solar eclipse, the clouds had parted. Yet, shortly after the Sun reappeared the clouds moved quickly in again. He said that for all the lead time up to the eclipse, throughout it and afterwards his views were accompanied by a large group of very loud local drummers.

Mike said that it had been a wonderful experience and that during the total eclipse Venus had become visible along with a large prominence on the left edge of the Sun's disc as well as a very asymmetrical corona. He explained that sometimes the inner planets can be seen during a total solar eclipse as it is only the overwhelming brightness of the Sun that prevents us from seeing them next to the Sun in space. Also, that the reddish prominence would be solar material that had been carried off the Sun's turbulent surface and lifted into space by powerful solar magnetic fields. He then added that the white wispy streaks of the corona that emanated in all directions from the eclipsed Sun were actually the Sun's outer atmosphere heading off into space. Sometimes the streaks were evenly spaced and at other times clumped together like fine strands of hair being blown out in a strong wind. The different shapes of the corona were reflecting the state of the Sun at the time of the solar eclipse.

Mike is already planning his next trip to see a total solar eclipse and this is in August next year in the USA. Its track begins by crossing the west coast in Oregon then curves across the Midwest states before leaving land on the South Carolina coast.


This article was written for the club news column of the Stratford Herald. The actual lecture explained the subject at a deeper level.