Without a NASA aircraft or U.S. funding. Mathematicians from the FME BUT are setting out to observe a total solar eclipse

Europe will witness a total solar eclipse on Wednesday, 12 August. The path of totality will cross the westernmost parts of Iceland, Greenland and Spain. The Solar Wind Sherpas team, led by mathematician Miloslav Druckmüller from the Faculty of Mechanical Engineering BUT, will travel to five observation sites. Due to significant cuts to science funding by the Trump administration, the Czech-American team lost part of its funding as well as the opportunity to use a specialised NASA aircraft. Nevertheless, the expedition will take place as originally planned thanks to a grant from the Czech Ministry of Education and financial support from the faculty.

A total solar eclipse occurs when the Moon completely covers the Sun's disc, briefly revealing the solar corona, which is normally hidden by the Sun's intense light. Bright stars and some planets also become visible in the sky. "The fact that we can observe a total solar eclipse is an incredible coincidence. No other body in the Solar System can create a total solar eclipse – they are either larger or smaller than the Sun. But from the Earth's perspective, the Moon appears to be exactly the same size as the Sun, making this breathtaking phenomenon possible," explained Miloslav Druckmüller.

The Brno mathematicians are setting off in pursuit of a total solar eclipse for the sixteenth time. For this year's expedition, they selected five observation sites in Spain and Iceland. Depending on the location, they will have approximately two minutes to capture their images. The sites were therefore chosen with regard to both the eclipse path and the likelihood of favourable weather conditions.

The Brno mathematicians have been collaborating since 2006 with the team of astrophysicist Shadia Habbal from the University of Hawaiʻi Institute for Astronomy on research into the solar corona. "The final image I create after the eclipse using specialised software is produced by processing photographs totalling around 100 GB of data. Despite the fact that we observe eclipses through the Earth's atmosphere and therefore under less favourable conditions than a space probe, our expertise combined with American funding has resulted in research demonstrating that total solar eclipses can produce images that still cannot be obtained from space by any other means," Druckmüller explained.

The data collected help astrophysicists better understand the physical processes that determine the structure of the solar corona and the sources of the solar wind.

The expedition affected by U.S. government funding cuts

During the most recent total solar eclipse over the United States and Mexico in April 2024, the Czech-American team was able for the first time to use a specialised NASA aircraft designed for high-altitude scientific research. The scientists had originally planned to use the aircraft for this year's eclipse as well as the following two. However, the extensive cuts to science funding introduced by the Trump administration have changed those plans. "Unfortunately, we lost the opportunity to use the NASA aircraft for our observations. The University of Hawaiʻi has also lost a substantial portion of its research funding," explained Druckmüller.

The Czech part of the team was able to partially compensate for the loss of funding thanks to a project awarded CZK 9 million over three years by the Czech Ministry of Education. The project, Investigation of Physical Processes Determining Coronal Structures and Solar Wind Sources Based on Observations of Heavy-Ion Emission During Total Solar Eclipses, began in March 2026 and will continue until 2029. It is funded under the INTER-EXCELLENCE II programme, INTER-ACTION subprogramme (Czech Republic–USA bilateral projects).

"This year, thanks to the project, we were able to acquire 16 equatorial mounts, cameras, lenses and laptops," added Pavel Štarha, the project's principal investigator and coordinator of the expedition's technical operations. The expedition also received financial support from the Brno University of Technology's Faculty of Mechanical Engineering.

Across the five observation sites, the team will operate a total of 15 DSLR cameras, 40 cooled cameras, 55 lenses and 20 control laptops. "This year's technical innovation is motorised focusing for manual lenses, which significantly speeds up equipment preparation, especially when weather conditions change rapidly," Štarha summarised. Students from the university's Fotoklub Technika also contributed to the development of the new components.

"Even if we hadn't secured the project funding, we would still have gone on the expedition. We probably wouldn't have travelled to Iceland, where prices have become extremely high because of the eclipse, but we would have travelled to Spain on a much smaller scale and covered the costs ourselves," said Druckmüller. "In 2008, we financed our expedition to Mongolia in exactly the same way. The PhD student who travelled with me earned the money by playing online poker," he added.

Students from BUT's Fotoklub Technika will also travel to Spain

A total of 28 expedition members will travel to Iceland and Spain. In addition to Czech and American scientists, BUT graduates and students will also take part in the expedition. Václav Široký, a student and head of the university's Fotoklub Technika, will be joining the expedition for the second time. "A total solar eclipse is an incredibly beautiful and irreplaceable visual experience, so it wasn't difficult to find enthusiastic club members willing to join me. For me personally, its appeal also lies in how demanding it is as a photographic discipline," said Široký, adding that managing as many as five cameras simultaneously is no easy task.

Watch a time-lapse of the 2024 total solar eclipse captured by Václav Široký.

Members of Fotoklub Technika will join Professor Druckmüller at the observation site on Mount Trigaza in Spain. The main observation site will be located near a former mountain hut at an altitude of 1,658 metres above sea level. If weather conditions are favourable, the researchers plan to carry lighter equipment to the summit at an altitude of 2,035 metres.

"The hut is abandoned, but it provides us with basic shelter. We can sleep inside in sleeping bags, prepare our meals on large gas stoves and collect water from mountain springs. We also have access to electricity thanks to a nearby transmitter," Široký described the practical arrangements for the expedition. The team also had to obtain all the necessary permits from the local authorities for their stay on the mountain.

About total solar eclipses The next total solar eclipse will occur on 12 August 2026. In the Czech Republic, it will only be visible as a partial eclipse, with the Moon covering approximately 85 per cent of the Sun's disc. The phenomenon will be observable in the early evening, around 7 p.m. The previous total solar eclipse occurred on 8 April 2024 and was visible primarily across the United States, Mexico, Canada and the central Pacific Ocean. The next total solar eclipse will be visible on 2 August 2027 and will be exceptionally long – lasting up to 6.5 minutes in places such as Egypt. The path of totality will begin in Spain and continue across North Africa (Morocco and Egypt) to Saudi Arabia. The Czech Republic will have to wait until 7 October 2135 for the next total solar eclipse.

The Solar Wind Sherpas is an international team of scientists who travel around the world to observe and collect data during total solar eclipses. The team – aptly named because of the enormous amount of equipment they transport to each (usually remote) observation site – is led by Shadia Habbal from the Institute for Astronomy at the University of Hawaiʻi in Honolulu. To date, the Solar Wind Sherpas have completed 15 eclipse expeditions, including to India (1995), Syria (1999), Libya (2006), China (2008), the Arctic (2015), Indonesia (2016) and Australia (2023).

The team is one of only a handful in the world to exploit the diagnostic potential of observing coronal emission lines at multiple wavelengths, leading to a number of discoveries and successful scientific publications. The researchers also study the invisible "colours" of the solar corona. Using cameras equipped with specialised filters and a custom-built spectrometer, they observe the behaviour of elements that have lost most of their electrons and emit light at very specific wavelengths. The most prominent of these elements include hydrogen, helium, iron, nickel, oxygen, carbon and calcium. Each contains clues to understanding the hot corona that escapes from the Sun and shapes the solar wind. More information about the Solar Wind Sherpas is available on the University of Hawaiʻi website.

Collecting the data is only the beginning of another demanding stage – data processing. This responsibility rests entirely with Professor Miloslav Druckmüller. The software he has been developing since 1999 extracts the maximum possible information from the data using mathematically precise methods. The remarkable level of detail revealed by combining dozens or even hundreds of images enables astrophysicists at the University of Hawaiʻi to gain new insights into the solar corona.

Solar eclipse is an astronomical phenomenon that occurs when the Moon passes between the Earth and the Sun, partially or completely obscuring it. This can only happen during a new Moon. Because the Sun is approximately 400 times larger than the Moon but also about 400 times farther away from the Earth, the Sun, Moon and Earth align in a straight line every 12 to 18 months. The Moon's shadow, around one hundred kilometres wide, darkens part of the Earth's surface even during daytime, causing temperatures to drop by several degrees. The glowing solar corona becomes visible around the Moon, while bright stars and some planets appear in the sky. Path of totality is the strip of the Earth's surface from which a total solar eclipse can be observed. Depending on the Moon's size and distance from the Earth, its width ranges from approximately 112 to 270 kilometres. Researchers always try to select observation sites with the highest probability of clear skies. Even a single cloud at the crucial moment can jeopardise an entire expedition, which is why several observation sites are usually prepared. White light is what we see with the naked eye during a total solar eclipse in the darkened sky. It consists of photons scattered by free electrons moving along the Sun's magnetic field lines. The Sun is, in essence, a giant magnet. Many people may remember a simple school experiment: placing a sheet of paper over a magnet and sprinkling iron filings on top. The filings arrange themselves into curved patterns connecting the magnet's north and south poles, making the magnetic field visible. During a solar eclipse, the role of the iron filings is played by electrons. Because they carry a negative electric charge, they are forced to follow the magnetic field lines of our nearest star.

Images of the solar corona by Miloslav Druckmüller are available at http://www.zam.fme.vutbr.cz/~druck/.

Source: Faculty of Mechanical Engineering BUT

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Author	Mgr. Radka Španihelová
Published	2026-07-29 12:19
Link	https://www.vut.cz/en/but/f19528/d351405