Maghrib: the prayer that moves five hours
In Paris, Maghrib is at 16:56 in late December and 21:58 in late June. No other prayer travels that far.
Five hours, and no angle to argue about
Fajr and Isha depend on how far below the horizon the sun has dropped, and authorities disagree about the figure. Maghrib does not have that problem: it begins at sunset, and sunset is sunset. It is the one prayer time that almost every method agrees on to within a minute.
What it gives up in ambiguity it makes up in movement. In Paris, Maghrib falls at 16:56 on 21 December and 21:58 on 21 June — just over five hours of travel. Nothing else in the day moves that far, which is why an evening routine built around it in winter bears no resemblance to the same routine in summer.
The sun you can see has already set
When the lower edge of the sun appears to touch the horizon, the sun is geometrically already below it. The atmosphere bends light around the curve of the earth and lifts the image by roughly half a degree — about its own width. You are looking at a sun that is not there.
Calculations account for this; the standard definition of sunset sits a little under a degree below the true horizon precisely to absorb refraction. So a timetable is not being pedantic when it disagrees with your eyes by a couple of minutes. It is describing the same moment with the distortion removed.
And the horizon in front of you is probably not flat
The calculation assumes an unobstructed sea-level horizon. Hills to your west hide the sun early; a high floor reveals it for longer. Two people in the same postcode can watch the sun disappear several minutes apart, and both are seeing something real.
This is the honest limit of any calculated time. It is right about where the sun is, and it cannot know what is in the way. Where a local mosque publishes a timetable, it usually carries a small margin for exactly this, and it is the one to follow.
In Ramadan it is two obligations at once
For eleven months Maghrib is a prayer. In Ramadan it is also the moment the fast ends, and a single time carries both. That is why people who never think about the difference between one app and another suddenly care about a two-minute discrepancy in the last hour of a fast.
The sensible practice is to settle on one source before the month begins — your mosque, or one app you trust — and stay with it. Comparing three timetables while waiting to eat produces anxiety and no additional accuracy.