Spain will experience a unique astronomical event this summer: a total solar eclipse. No total eclipse has been visible from the Iberian Peninsula since 1905, although one did pass over the Canary Islands in 1959. It will therefore be an extraordinary occasion for millions of Spaniards, many of whom will be enjoying this unparalleled sensory experience for the first time. Here are the key things you need to know to make sure you don’t miss this phenomenon.

When is the solar eclipse?

The eclipse will take place on Wednesday, August 12, shortly before sunset. The peak of the event will occur at around 8:30 p.m., although the exact timing will vary depending on the location within Spain. The eclipse will first make landfall along the coasts of Galicia and Asturias at around 7:30 p.m., and it will become total nearly an hour later.

Where will this astronomical phenomenon be visible in Spain?

The upcoming solar eclipse will be total across almost 40% of Spain, along a band that crosses the northern part of the country, entering via Galicia and Asturias and exiting over the Mediterranean coast and the Balearic Islands.

The path of totality will pass through 13 of Spain’s 17 regions, covering at least part of 31 of the country’s 50 provinces. In the rest of Spain, the eclipse will still be visible as a deep partial eclipse.

Is the eclipse visible only from Spain?

Spain will be the only country from which the eclipse can be observed under truly favorable conditions, although the path of totality will also cross uninhabited areas of Greenland, the western tip of Iceland and a small corner of Portugal.

How long will it last?

In areas within the path of totality, night will seem to fall twice that day. During the first of those moments, at around 8:30 p.m., weather permitting, observers will see a black sun encircled by a white halo, with totality lasting for up to 1 minute and 50 seconds.

Is it a one-off event?

Spain will experience three top-tier solar eclipses in three consecutive years: on August 12, 2026, August 2, 2027, and January 26, 2028. The first two will be total solar eclipses, while the third will be an annular eclipse.

Which locations should be avoided?

The main drawback is that the eclipse will reach Spain as the sun is setting. As a result, obstacles near the horizon, such as buildings, trees and mountains, may block the view. For example, the eclipse will not be visible from places such as San Lorenzo de El Escorial, near Madrid, which sits on a mountainside that obscures the sunset.

The other factor that could ruin the spectacle is cloud cover, which will depend entirely on local weather conditions on the day.

How can you find the perfect viewing spot?

The standard advice, to find a location with an unobstructed view of the horizon between west and northwest, may leave many people wondering where exactly to go. Three free apps and a website can help eclipse chasers identify the best viewing locations, without necessarily having to use one of the official viewing areas designated by public authorities.

How can you watch it safely?

The only safe way to look directly at the sun during any phase of the eclipse is to use certified eclipse glasses that comply with the ISO 12312-2 standard and are properly marked with both that certification and the European Union’s CE mark.

The glasses must also display the manufacturer’s address, instructions in the language of the country where they are sold, and an expiration date.

“It terrifies me that anyone would even suggest using X-rays or photographic negatives,” warned Juan Cruz Cigudosa, Spain’s secretary of state for science.

Is a 99% eclipse very different from a total eclipse?

Yes. A 99.9% eclipse and a total eclipse are far from the same experience. Only during totality does the solar corona become visible and the sky take on a nighttime appearance.

For example, in central Madrid the sun will be obscured by 99.96%, but experts stress that even such an extreme partial eclipse bears little resemblance to the sensations experienced during totality. Those in some of the city’s northernmost neighborhoods may be able to glimpse totality for a few seconds at around 8:32 p.m., but only from certain streets.

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