It gets the name because totality on 2 August 2027 will reach 6 min 23 s, and so far in the 21st century only one eclipse has lasted longer: the one on 22 July 2009, with 6 min 39 s. That makes it the second-longest totality of the century. “Eclipse of the century” is a press nickname, and Space.com uses it in several of its headlines about this eclipse. From Spain it will be a good deal shorter: 4 min 48 s in Ceuta, the Spanish city on the African side of the Strait of Gibraltar and the longest in the country.
What NASA’s catalogue says
NASA’s catalogue of solar eclipses from 2001 to 2100, compiled by Fred Espenak, gives the duration of totality for each eclipse on the central line, at the point of greatest duration. Of the century’s total eclipses, only four go beyond six minutes:
| Total eclipse | Maximum duration | Where the maximum falls (NASA catalogue) |
|---|---|---|
| 22 July 2009 | 6 min 39 s | Pacific, 24° N 144° E |
| 2 August 2027 | 6 min 23 s | Egypt, 26° N 33° E |
| 2045 | 6 min 06 s | 26° N 79° W |
| 2096 | 6 min 06 s | 27° N 153° E |
There are 16 seconds between the 2009 and 2027 eclipses, and both have been given the same nickname. Space.com admits as much in an article about the name: in 2009 everyone was already talking about the “eclipse of the century”, so strictly speaking the 2027 one can’t be it.
The same family as 2009
They are alike because both belong to saros 136, the same series of eclipses: NASA’s table says so for 2027 and Wikipedia for 2009. A saros lasts about 18 years, 11 days and 8 hours; after that, the Sun, the Moon and the Earth return to almost the same geometry and a very similar eclipse repeats. Those extra 8 hours mean the Earth has turned a third of the way round, so the next eclipse falls about 120 degrees further west: the 2009 eclipse had its maximum in the Pacific, south of Japan, and the 2027 one has it in Egypt.
The long totalities of recent decades come from this series. According to English Wikipedia, the previous eclipses lasted 6 min 53 s (11 July 1991), 7 min 04 s (1973) and 7 min 08 s (1955). Each turn of the saros has come out a little shorter than the one before, which is why 2027 falls short of 2009.
What about “the longest over land”?
In 2009 the maximum duration fell in the open ocean, south of the Bonin Islands, and anyone who wanted to see it up close had to go by boat. In 2027, NASA puts the maximum duration, 6 min 23.2 s at 10:00:21 UT, at 26° 49’ N 31° 08’ E: on land, in the desert west of Sohag, in Egypt. And Luxor, with its temples inside the path, will get 6 min 23 s according to our engine.
Space.com goes further and writes that, without question, it is the longest eclipse of the century over land. We don’t claim that, because English Wikipedia gives Akusekijima, an inhabited Japanese island, 6 min 26 s of totality in 2009: three seconds more than the 2027 maximum. Nor do we say until what year there won’t be a longer one, because the dates going around don’t agree with each other.
And in Spain?
In the Spanish part of the path totality is shorter, partly because the shadow moves almost twice as fast over the Strait of Gibraltar as over Egypt (we explain why here). With the durations published by the IGN (Spain’s National Geographic Institute):
- Ceuta: 4 min 48 s, the longest in Spain.
- Tarifa: 4 min 38 s.
- Melilla: 4 min 34 s.
- Algeciras: 4 min 26 s.
- Cádiz: 2 min 54 s. Málaga: 1 min 49 s.
The shadow comes in over the coast of Cádiz province and leaves over the coast of Almería: the maximums for the 105 municipalities with totality run from 10:46 to 10:51 mainland Spanish time (CEST, UTC+2), with the Sun high in the sky. In Will I see it? you’ll find the seconds for your town. The whole route, from the Atlantic to the Indian Ocean, is in the shadow’s journey, and the six-plus minutes in Egypt are covered in the eclipse in Egypt.
Sources: Catalog of Solar Eclipses: 2001 to 2100 — NASA (the century’s totalities over six minutes and where their maximum falls); Solar Eclipses: 2021 - 2030 — NASA (type, duration and saros 136 for the 2027 eclipse); Path of the Total Solar Eclipse of 2027 Aug 02 — NASA (maximum duration, time and coordinates); Path of the Total Solar Eclipse of 2009 Jul 22 — NASA (where the 2009 maximum duration fell); Solar eclipse of July 22, 2009 — Wikipedia (saros 136, the earlier eclipses in the series, the maximum over the ocean and the 6 min 26 s at Akusekijima); Why is the 2027 total solar eclipse being called the ‘eclipse of the century’? — Space.com (the nickname, the boats of 2009, the length of the saros and its shift westwards); IGN — eclipses.ign.es (in Spanish: durations of totality in Spain); eclipseando data (skyfield engine + DE440s: Luxor and the times of maximum in Spain).
If you would like something to keep from the eclipse, the shop prints T-shirts, mugs and posters with the name of your town, the time of its maximum and its seconds of totality. See the merchandise →
Remember: never look at the Sun without proper eye protection (filters made to EN ISO 12312-2). The official reference for safe viewing in Spain is the IGN (in Spanish): eclipses.ign.es.