Learn
The school of the eclipse
On 12 August 2026 the Moon’s shadow will cross Spain coast to coast. These five short lessons explain — with hand-drawn diagrams and data from the IGN and NASA — exactly what you will see, why, and how to make the most of every second. The full illustrated lessons are on our Spanish pages (the diagrams speak every language); each card below gives you the lesson in English first.
- Lesson 1 · Geometry
How a solar eclipse works
The 400-to-1 coincidence: the Sun is about 400 times wider than the Moon and about 400 times farther away, so their discs match almost exactly. Umbra vs penumbra, and why there is not an eclipse every new moon (the Moon’s orbit is tilted ~5°).
- Lesson 2 · The path
Why total in one village and partial in the next
The path of totality is the narrow strip swept by the umbra; its edge is a hard line. Madrid is the textbook case: 99.9% covered and still no corona, no darkness — the last 0.1% makes all the difference.
- Lesson 3 · The reward
The solar corona
The Sun’s outer atmosphere, a million times fainter than its surface: only visible to the naked eye during totality. Corona, chromosphere and prominences — what you are actually there to see.
- Lesson 4 · The magic seconds
Baily’s beads and the diamond ring
The sequence of the final seconds before totality: sunlight breaking through lunar valleys (the beads), then the single last blaze (the diamond ring) — the visual cue for when the glasses come off, and when they must go back on.
- Lesson 5 · What comes next
2026, 2027, 2028: three eclipses in a row over Spain
A historic run: the total eclipse of 12 August 2026, the great southern total eclipse of 2 August 2027 (Cádiz and Málaga) and the annular eclipse of 26 January 2028. Keep your glasses (source: IGN).
- Tool · For your party
Full-screen countdown
Cast it to the TV: a countdown to the exact second of totality in your municipality, with a totality alert. (Interface in Spanish — it is a clock.)
From theory to your town
Theory is lovely, but what matters is what happens over your head. We have computed the eclipse circumstances for all 8,217 Spanish municipalities (our own computations with JPL DE440s ephemerides, cross-checked against the IGN): exact time, percentage of Sun covered, totality duration and Sun altitude.
Will I see it from my town? See the eclipse map
And remember: to look at the Sun during the partial phases you need certified glasses (EN ISO 12312-2). How to check yours, in our glasses guide and in the official guidance at eclipses.ign.es.