Open the project’s own municipality table and look up Madrid or Barcelona on 12 August 2026, and the magnitude column reads 1 — the same rounded figure that shows up for cities squarely inside the totality band. And yet, in the very same record, the field that actually decides the headline — totalidad — reads false for both. No corona, no darkness, no diamond ring. A number that looks identical to the towns that get the full show, attached to a flag that says they don’t get it at all.
What the numbers actually say
Eclipse magnitude measures how much of the Sun’s diameter the Moon covers, with 1.000 as the threshold: below it, a sliver of the photosphere always remains uncovered, however thin. In the project’s data, totality cities — A Coruña, Oviedo, Santander, Bilbao, Burgos, Zaragoza, Castelló, València, Palma — all carry a magnitude of 1.03: the Moon’s disc is comfortably larger than the Sun’s from those vantage points, with margin to spare. Madrid and Barcelona’s entries show 1 flat, and totalidad: false.
That combination only makes sense one way: the real magnitude at those two cities sits a hair under 1.000 — in the thousandths, not visible at the two-decimal precision the public dataset stores. Close enough to round up to a number that looks total. Not close enough to actually be total. The astronomical definition of totality is binary — either the disc is fully covered or it isn’t — and Madrid and Barcelona land on the wrong side of that line by a margin too small for this dataset to spell out in digits, but large enough for the flag to be unambiguous.
Why a sliver ruins the whole effect
This isn’t a rounding curiosity — it changes the entire experience. As long as any part of the Sun’s photosphere is exposed, it outshines the corona by a factor of hundreds of thousands: no darkening sky, no visible corona, no drop in temperature, nothing that reads as “total” to an observer on the ground, no matter how thin that remaining crescent gets. A 99%-covered partial eclipse and a 20%-covered one look, to the naked eye and without proper filtration, essentially the same: dimmer daylight, an odd crescent shape if you check through eclipse glasses, and nothing else. The entire spectacle people travel for — the corona, the sudden dusk, the horizon glow in every direction — switches on only at the instant the last sliver disappears. Madrid and Barcelona never reach that instant.
What Madrid and Barcelona get instead
According to the site’s own FAQ, both cities “will see a very high partial eclipse, but the solar disc will never be fully covered at any point” — with the Sun at just 7° altitude over Madrid and 4° over Barcelona at maximum, and eclipse-glasses-only viewing running the entire time, from first contact (19:36:41 in Madrid, 19:34:59 in Barcelona) through to sunset itself (21:16:20 and 20:54:49), since the partial phase in both cities is still running when the Sun sets.
The actual lesson
If your goal is to experience totality — the corona, the darkness, the whole reason people call this a bucket-list event — magnitude alone won’t tell you whether a city qualifies; you have to check the boolean, not just eyeball a number that rounds the same as everywhere else. The band itself, not proximity to two big cities, is what decides who gets the real thing.