Mª Ángela del Castillo Alarcos
This event has not occurred on the Iberian Peninsula since 30 August 1905 (there was another in 1912, but it was a total annular eclipse), although we have had partial eclipses and two annular eclipses. That is why there is so much excitement surrounding this major event. The path of totality will move from west to east across the north of the peninsula, reaching as far as the Balearic Islands. Cities such as Madrid and Barcelona will not be within the path of totality, so they will observe the eclipse during the partial phase, as will the rest of Spain.
The first partial phase will last around 55 minutes until the Sun is completely covered by the Moon and darkness falls, as if night were falling, but this will be very brief: in the central zone, totality will last barely two minutes (1 minute 49 seconds), whilst to the north and south of the central path of totality, the duration of totality will be even shorter. Once this period has passed, daylight will return, and the second partial phase will begin until the Moon has completely moved away from in front of the Sun. This will only happen in the westernmost regions, because in the rest of the country, towards the Mediterranean, as the Sun sets earlier, it will already have disappeared below the horizon by the time the second partial phase begins.
To view it properly – as it will be very close to the horizon during totality – you should find a spot free from obstructions such as houses or mountains, and two or three days beforehand, test the location by watching the Sun set to ensure that the chosen spot offers a clear view at the specified time. Every town and city in Spain (including the Canary Islands) can look up an infographic on the National Geographic Institute’s website containing all the local timing details (IGN Eclipses), which will also provide information on the next solar eclipses that, fortunately, we will be able to see from Spain in the coming years (a total eclipse on 2 August 2027 and an annular eclipse on 26 January 2028).
To observe the eclipse, it is essential to use eye protection, given that we now know how dangerous the sun’s rays can be to our eyesight, even though during the eclipse the Sun will be very close to the horizon and its brightness will appear less dangerous. Approved eclipse glasses (ISO 12312-2) bearing the European Community’s CE mark are ideal, as, as well as being very inexpensive (€2 or €3), they offer maximum protection. These should be used during the first and second phases of the eclipse. As soon as the Sun is blackened and obscured by the Moon, the glasses should be removed so you can enjoy the darkness and the solar corona that will appear around the Sun’s disc – the only way to see this faint corona, which is otherwise impossible to observe (apart from using coronagraphs at astronomical observatories or solar space telescopes).
It is very important that children are protected when watching the totality; they may take their glasses off and put them back on, bend them or throw them on the ground, which could damage them. That’s why a good tip is to make a hole in the arms of the cardboard glasses and tie a small string or elastic through it so that when they take them off, they hang around their neck; or, for a really fun touch, get a cardboard mask of an animal or children’s character – the sort with eye holes – and stick the glasses onto the back of the mask, which will be held in place by the elastic band it usually has.
All that remains is to hope for clear skies and enjoy an event of this calibre, which will make us feel as though it’s night in the middle of the day, allow us to admire the solar corona – the only way to observe it – and see some stars and planets alongside the Sun. Also, sometimes, when the Moon’s edge (known as the lunar limb), just before it covers the Sun, has gaps between mountains or craters, and the Sun’s rays escape through those gaps, forming pearls of light or a flash known as the ‘diamond ring’—another spectacle we’ll see if it occurs.