For the team of mathematician Miloslav Druckmüller it was already the tenth solar eclipse expedition, but still, it was unique: "This year, for the first time, we captured the corona at a time when the activity of the Sun is approaching the minimum. Even an amateur, looking at our photo, can recognize that the Sun is like a huge magnet with two poles. The power-lines of magnetic field come out at the northern magnetic pole and then enter the opposite pole. If the Sun is at its near the maximum of its activity, as was the case in the year 2013, even an expert has almost no chance to find out where the magnetic poles are, because the magnetic field has a very complicated structure, " said Miloslav Druckmüller, the leader of the expedition.

Professor Druckmüller has created an unique software for mathematical image processing of data obtained during total solar eclipse expeditions. One of the most important results are high resolution images of the K-corona, which is a light scattered on free electrons and images showing the distribution of different iron, nickel and argon ions, which allow a perfect diagnosis of conditions in the Sun´s corona.

This year, another member of the expedition, mathematician Pavel Starha, created a new software for cameras control. "This software is specially developed for observing total solar eclipse of the Sun and it is designed to make it as easy as possible to work at different observation spots with different climatic conditions. There was a different equipment at each of the five observation places, so the software had to be flexible to work with a variety of cameras," Pavel Starha explained. Thanks to this unique software and the perfect weather that prevailed during the time of the solar eclipse in the US, Czech mathematicians received the largest amount of valuable data in history of Czech solar expeditions which occupy about 3 TB.

The Tenth Total Solar Expedition was supported by grants from NASA, NSF, the American Astronomical Society to the PI, Shadia R Habbal of the Institute for Astronomy at the University of Hawaii, and from Peter Aniol ASTELCO. The researchers were located on five different places in the US. The main observing place where worked Miloslav Druckmüller and Pavel Starha was in Oregon, where the team rented a private plot from a local farmer for the scientific observation. "Thanks to that, we stayed away from the crowds of tourists who were attracted by a huge media and marketing campaign of the Great American Solar Eclipse. The Sun's eclipse became a well traded item in the US, and we have never seen it before," added Druckmüller.

The most physically challenging journey was undergone by mathematician Jana Hoderova. Her observation place was high on the Whiskey Mountain (3 400 meters above the sea level). So all the equipment and devices had to be brought on the horses. "We would not be able to get the equipment to that place because of the terrain. We had to ride horses for almost two hours. The horses were not interested in the fact that they carry a huge and bizarre suitcases with very expensive equipment. Fortunately, we transported everything with no damage," said Jana Hoderova, who had taken several riding lessons before the expedition.

Each expedition means many months of preparation and enormous stress, but mathematicians from Brno University of Technology agreed that the total solar eclipse itself is worth it. "But the truth is that I never enjoyed those tens of seconds of total solar eclipses. I had a deep feeling of responsibility for the entire expedition. We have had been working intensively for many months and the project itself is very demanding because we were working continuously and under big pressure even 16 hours a day. Unique images of the solar corona can only be resolved after returning to my office," explained Druckmüller, whose photos of the Sun's corona were published on the front page of prestigious Nature magazine and also in the Editors' Choice of Science magazine.

Another total solar eclipse will happen on 2nd July 2019 in South American Chile and the Czech team led by Professor Druckmüller will be there as well. "We are going to the Chilean expedition because it is definitely the best place to observe the solar eclipse in the coming years.