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Solar eclipses have gone through many phases throughout history. First they became objects of worship or spreaders of panic, depending on the civilization we are talking about. Later, once their origin was better understood, they became a very specific but extremely useful tool for astronomers, as it was the only way they could study the solar corona. Nowadays, no one (or almost no one) fears eclipses and scientists have tools that can replace them when studying the corona. However, they have not stopped being special. Now we have entered a new phase. A stage in which society enjoys them Instead of fearing them, scientists witness from the outside how the love of heaven that one day led them to choose their profession arises in other people. I have talked about this and much more with David Galadiastronomer, professor at the University of Córdoba and member of the Scientific and Advisory Commission of the Trio of Eclipses. The end of an era For a long time, solar eclipses have been used to study qualities of the Sun or Moon that are not normally measurable or visible. A solar eclipse was even used to prove Einstein’s Theory of Relativity. However, possibly those that stand out the most are the studies on the solar crown. That is, the outermost layer of the solar atmosphere. It is composed mostly of plasma, an ionized gas, whose atoms have gained or lost electrons, acquiring an electrical charge. This moving gas is what makes up the solar winds. It is also in the corona that coronal mass ejections are formed, which serve as the origin of geomagnetic storms. For all this, studying the solar corona is essential for scientists. However, there is a problem. The center of the Sun is so bright and it has such a dim glow that normally cannot be seen with conventional observation instruments. There is only one exception: a total solar eclipse. When the Moon completely covers the Sun, its brightness can no longer hide the solar corona from us and it suddenly appears in the sky. For decades, scientists had a few minutes with each eclipse to study it. Nowadays, fortunately, it is no longer necessary, since there are coronagraphsinstruments that have the ability to artificially “eclipse” both the Sun and other stars, revealing what we normally cannot see. However, there are still a few qualities that can only be studied in eclipses. “Coronographs cover not only the solar disk, but must also cover, due to unavoidable design needs, the chromosphere and the lowest part of the solar corona,” explains Galadí. “However, these regions can be observed well during a total solar eclipse.” On the other hand, “the coronagraph removes light from the solar photosphere, but does not reduce the brightness of the overall sky, so the outermost and faintest parts of the corona are also lost using these instruments.” Therefore, today we know the Sun and the Moon much better. The theory of general relativity continues to be constantly tested with new discoveries in the field of astronomy. And yes, you can study the solar corona without having to see a solar eclipse. However, these instruments prevent us from seeing it with the same clarity that we see it when the Moon completely eclipses the Sun. “Here we have the only two residues of heliophysics for which eclipses are still useful: the study of the link between the solar photosphere and the middle corona through the chromosphere and the lower corona, and to analyze the outermost coronal regions”. Now, in the future solar eclipses will not be necessary even for that; Well, there are already two missions underway aimed at solving the problem. “The observation of the external corona from space, with coronagraphs on artificial satellites, such as the Solar and Heliospheric Observatory (SOHO) of the European Space Agency in collaboration with NASA, avoids all the disadvantages due to the Earth’s atmosphere and its brightness,” says the astronomer from the University of Córdoba. “In addition, we have great technological innovations such as those of the mission Proba-3 (also from ESA), which are already allowing us to study the chromosphere and the lower corona from space, precisely by creating artificial eclipses.” Does all this mean that scientists will no longer have anything to study during a solar eclipse? Perhaps for astronomers there will come a time when they can focus only on looking at the sky and enjoying themselves. For other scientistssuch as those specialized in animal behavioralthough some studies had already been published previously, the real party begins now. “In animal ethology it is interesting study behavior when a sudden night occurs, uncoupled from other circadian rhythms,” says Galadí. “The behaviors of species when ‘turning off’ the Sun suddenly can only be due to the change in ambient light and temperature, but not to other external or internal factors.” The solar eclipse is now for society This August 12, 2026, there will be thousands or even millions of people who will travel or look for the best places near their homes to view the solar eclipse. These astronomical phenomena have become milestones that transcend far beyond science. It is time for society to enjoy them. David Galadí is clear about it: “Total solar eclipses are no longer science, or have almost ceased to be science, but they continue to constitute great natural spectacles with enormous potential to surprise people.” This can occur at many levels. “They have power as a source of artistic inspiration, tourist resourcean inexhaustible source of didactic or informative applications, and the ability to awaken vocations.” In fact, the latter is something in which he himself sees himself reflected. “Great astronomical events mark people, I myself am a product of the astronomical fever of Halley’s comet in the eighties.” In Spain we have a great opportunity, because It is not a single eclipse. Next year we will have another total solar eclipse and in 2028 an annular eclipse, which will provide new opportunities to enjoy them … Read more