A unique ninety seconds in the 21st century: Spain prepares for historic eclipse trio

Up to 12 regions will witness an astronomical event not seen on the peninsula for more than a century, bringing a major economic boost to inland Spain. On 15 April 1912, just two days after the sinking of the Titanic in North Atlantic waters, Spain experienced its last total solar eclipse for just a few seconds, classified as hybrid because of the unusually narrow width of its path of totality. Issue 33 of the magazine of SAE, the Spanish Astronomical Society, recorded the event with testimonies from several Galicians who witnessed this fleeting phenomenon. "The landscape looked sad and wan, and the cold was quite intense. The hens were looking for their roost and one that I saw, which had her chicks, sheltered them beneath her wings," recounted Tomás Martínez, a teacher from O Barco de Valdeorras, about the event he witnessed at 11:49 from his latitude in Ourense. For the first time since then, the country is preparing to host this phenomenon in two consecutive years (on both 12 August 2026 and 2 August 2027), plus a third annular solar eclipse on 26 January 2028, which together will form a unique trio of eclipses in 21st-century Europe. The next solar episode will only be seen in totality from northern Siberia, the east coast of Greenland and western Iceland before crossing Spain through up to 12 autonomous communities in a band 293 kilometres wide. A real astronomical lottery, yes, though also an economic one because of the geographical circumstances.From Canada, the north-east coast of the United States and north-west Africa it will also be visible, but only partially. The term eclipse comes from the Greek 'ekleipsis', meaning disappearance, and has several forms. Solar eclipses occur only at new moon, when the disc of our satellite exceptionally manages to cover the Sun completely. This produces a sudden spell of darkness for a few moments while a black sphere can be seen. If the Moon's orbit were not tilted, this phenomenon would occur twice a month in specific areas of the Earth, both at new and full moon. _"_As soon as the Moon completely covers the Sun, the brightness decreases. We can start to pick out the brightest stars and planets in the sky. If we are in the countryside, we will hear the birds singing. And just as totality begins, the birds stop singing because they think night is falling," explains César González, an astronomy populariser at the Madrid Planetarium, putting into professional words the testimony that teacher Martínez gave 114 years ago to the SAE. "The temperature drops. It can fall by as much as five degrees, and a slight breeze always starts to blow," adds this scientist. It is in that brief moment that lucky observers can remove their special, fully approved glasses (this can be checked by the ISO 12312-2:2015 certification on one of the arms), since during the partial phases the risks to eyesight are high. Without the glasses, ultraviolet radiation will damage the eye's photoreceptors (cones and rods), while infrared energy will produce a direct thermal effect on the retina, causing solar retinopathy. The symptoms of this condition, which will take time to appear, can include blurred vision, spots or scotomas at the point of greatest visual acuity, metamorphopsia (a distorted perception of shapes) and a reduced tolerance to light, or photophobia, which can cause headaches. The total phase will not exceed 1 minute and 48 seconds - the closer you are to the line of totality, the more seconds you will be able to enjoy the phenomenon - anywhere along its path over Spain, so it is important to time it and to bear in mind that, depending on where it is observed, the event will start and end at different times. The trajectory of the eclipse enters Spain through north-west Galicia at around 19:27 and will end in the Balearic Islands at around 20:35. Cities just outside the band, such as Madrid or Salamanca, will see a deep partial eclipse (at least 92% dimming across the whole Peninsula) but not totality. So how do scientists calculate all this? "We know the laws that govern the movement of planets and satellites and, in inverted commas, it is not too difficult to work out when they are going to happen, even in the distant future (...) By using computer tools to find out about eclipses in the past and comparing them with historical events, it is possible to link phenomena together," explains César González. Long before modern calculations, scientists already knew that eclipses follow certain patterns. González points out that the Sumerians, around 5,000 years ago, may already have identified them. The best-known cycle is the Saros, of approximately 18 years, 11 days and 8 hours, because after that period the geometry between the Sun, the Earth and the Moon becomes very similar again, but there is also the exeligmos, which is equivalent to three Saros cycles and makes it possible to calculate more precisely from the place where it is observed. Hotel bookings fully taken in Spain's emptied-out interior The eclipse passes directly over provinces such as Soria, Guadalajara and Teruel - the area known as Spain's Siberia because of its low population density - as well as the four Galician provinces, all of Castile and León except Salamanca, the Principality of Asturias, Cantabria, the Basque Country, Navarre, Aragon, Castile-La Mancha (in Guadalajara and Cuenca), the south-west of Catalonia, the Valencia region (Castellón and Valencia) and all of the Balearic Islands. The Spanish Rural Development Network estimates that the trio of eclipses could generate an economic impact of close to 1.4 billion euros, which, with the exception of the coastal provinces, will be spread across areas generally far removed from the interests of the bulk of foreign tourists. The second solar eclipse, in 2027, will last longer (up to five minutes) but over a smaller geographical area (Cádiz, Málaga, Granada, Almería, Ceuta and Melilla), and will also be competing with other Maghreb countries. In April, the Presidency Councillor of Castile and León put the estimated number of visitors to the region attracted by this first eclipse at two million. And the tourism portal of the Generalitat Valenciana forecast an 80% surge in bookings in inland Castellón, in a region where tourism is concentrated on the Valencian and Alicante coasts. For those visitors who cannot come to Spain to enjoy the total eclipse, ESA will broadcast the phenomenon live from the Javalambre Astrophysical Observatory in Teruel, as well as organising a free public observation programme in the city of León in collaboration with the university and the city council. \n