The 2027 total solar eclipse in Tunisia

Which towns are inside the path

The path of totality crosses Sfax, the Kerkennah Islands, El Jem, Djerba and Gabes. It does not cross Tunis, Sousse, Monastir, Hammamet, Sidi Bou Said or Matmata, which see a partial eclipse only. NASA's own pages list Tunisia among the countries where the eclipse is total (NASA Science), and its path table puts the path 246 to 248 km wide across the country (NASA path table).

NASA publishes the path and the elements that describe it, and no table for a town. The figures below marked "our working" are the result of running NASA's own published calculation, the code behind its eclipse explorer, with the elements on its page for this eclipse. We checked it first at NASA's point of greatest eclipse, in Egypt, where it returns 10:06:38 UT and 6 minutes 22.5 seconds against NASA's published 10:06:37.7 UT and 6 minutes 22.6 seconds. These are our figures and not NASA's, and where a published figure exists we print it beside ours.

Places inside the path

Times are Tunisian time, which is UTC+1 all year with no daylight saving (timeanddate), cut to the minute as the published tables print them. Coordinates are Wikipedia's for the towns, except Sfax, which is NASA's own city list, and Galaxy Tours' GPS for the three Star Wars sites and Maguer Gorge, so those are approximate. Published figures are Spain Solar Eclipse's. Close to the edge of the path, a few kilometres change the duration by many seconds, which is why Tozeur is 1 min 39 s on our working and 1 min 46 s published. Treat a duration near the edge as approximate.

The Mos Espa set, Ong Jemel and Maguer Gorge are inside the path on these coordinates, with about two to three minutes of totality. The sites around them are not, as the next table shows. Which sites are which, and what was filmed at each, is in Star Wars filming locations in Tunisia.

Places outside the path

A place outside the path sees a partial eclipse, however close to the edge it is. The fraction of the Sun's diameter covered at the maximum is the eclipse magnitude, and below 1.0000 the Sun is never fully covered. Some sources print instead the share of the Sun's disc that is covered, which is the share of its area and not of its width, and which reads a little higher for the same place.

Our working, with the same coordinates as above. The share of the disc is as Spain Solar Eclipse publishes it. Hammamet's coordinates are approximate and not from a source. Even 99.93 percent of the disc, which is Monastir's figure, is not totality.

Nefta, the Hotel Sidi Driss at Matmata, the Lars homestead dome and Gour Beni Mzab are all outside the path, at magnitudes from 0.9974 to 0.9993. With margins this small, a few kilometres can settle it, so if you are coming for totality, ask us about any place that is not in these tables.

How long totality lasts, source by source

Published durations for Sfax and Kerkennah run from 5 minutes 38 seconds up to about 5 minutes 45 seconds. None of them is wrong. They answer slightly different questions.

Three things cause the spread. The sources choose different observing points: a town centre, or the centre line of the path, which runs some 15 to 30 km farther south than those two places. They use different values of delta T, the difference between Terrestrial Time and Universal Time: 71.7 seconds on NASA's page for this eclipse, 72.8 seconds on EclipseWise, 76.0 seconds in NASA's explorer and 0 seconds on timeanddate. And they model the edge of the Moon slightly differently.

What time it is

Tunisia is on UTC+1 all year. On our working, totality starts between about 10:05 and 10:12 in the morning anywhere in the country, and the Sun stands 53 to 57 degrees above the horizon.

Our working at Sfax and Kerkennah, from NASA's elements, cut to the minute. The sources named print the events listed.

The spread of published times comes from three things that are easy to mix up.

• Different events. Space.com's "10:09 CET" at Kerkennah matches the start of totality there. Most other sources quote the maximum, 10:11 to 10:12. Neither is wrong. They are different events.
• Two kinds of time. NASA lists the greatest eclipse at 10:07:49.4 Terrestrial Dynamical Time, which is 10:06:37.7 UT. EclipseWise writes "10:07:50 TD (10:06:37 UT1)". Quoting the first as though it were a clock time overstates it by about 72 seconds.
• Different places. A time or a duration worked out on the centre line of the path and one worked out for a town are not the same figure, because they are different places.

NASA's own centre line across the country, with the Tunisian time beside NASA's Universal Time:

From the NASA path table. The centre line passes near Kasserine and Sidi Bouzid, and then just south of Sfax and Kerkennah, on our reading of the coordinates. The greatest eclipse of all is in Egypt, with 6 minutes 22.6 seconds on NASA's page, and the greatest duration, 6 minutes 23.2 seconds, is also in Egypt.

Where sources disagree

• Durations. 5 min 38 s to about 5 min 45 s, as above, and for the reasons above.
• Whether Tunisia is on the list. EclipseWise's summary page lists the regions where the eclipse is total as Morocco, Spain, Algeria, Libya, Egypt, Saudi Arabia, Yemen and Somalia, and leaves Tunisia out (EclipseWise). NASA's pages include Tunisia and its path table crosses the country.
• One outlier. A search excerpt of another site put totality at Sfax about 85 minutes after every other source and our working. We did not open the page and we treat it as an error.

Weather

It is midsummer. In August the weather service's average daytime high is 102.7F (39.3C) at Tozeur and 92.3F (33.5C) on Djerba. The Kairouan station, the closest to El Jem, reads 99.5F (37.5C). Its table has no station for Sfax or Kerkennah (Institut National de la Météorologie).

Cloud is a separate question, and two published statistics speak to it. They are not forecasts, and they do not measure the same thing, so they cannot be compared. Space.com puts the chance of cloud on Kerkennah at 21 percent. timeanddate records that day as cloudy for 2 percent of the time at Sfax since 2000.

Watching safely

NASA says you can look at the eclipse without eye protection only during totality, when the Moon completely obscures the Sun's bright face. During the partial phases before and after totality, eclipse glasses or a solar viewer must stay on, and they ought to comply with the international standard ISO 12312-2. Regular sunglasses, no matter how dark, are not safe for viewing the Sun (NASA Science).

The trip

For the trip built around the path, see our eclipse expedition page. We confirm availability on the call.

What we could not verify

• A static NASA table for Sfax or Kerkennah. None exists. The figures marked "our working" are the result of NASA's own calculation and are not published by NASA.
• What NASA's explorer prints for Sfax in a browser. Our run uses the same code and elements, so it should agree to within seconds.
• The coordinates each third party site used, which is part of why their figures differ.

Sources