Sunset and sunrise times vary with altitude. This has consequences for the timing of prayers and breaking of the fast on skyscrapers and mountains,as well as in planes (How much? We’ll see shortly.) But this is not as new a phenomenon as one might think, and even people on the ground might need to make some adjustments regarding sunset time. Read on if you are interested!
About 1,100 years ago, the Hanafi jurist Ibn Abi Musa was asked by the people of Alexandria (Egypt) about the time of iftar (breaking the fast), given that someone atop the Lighthouse of Alexandria would be able to see the sun for a significant length of time after it had clearly set (disappeared) for people on the ground. He replied that those on the ground can break their fast when they see the sun as having set, but those atop the lighthouse are not allowed to break the fast as long as they can still see the sun. [Badai` al-Sanai`, DKI, 2/576]
The lighthouse (منارة) of Alexandria (a.k.a Pharos) was built in the 3rd century BC, commissioned by Ptolemy I (although various legends attribute it to Alexander the Great and others). It was over 100m high, probably built from limestone, and was one of the Seven Wonders of the Ancient World. According to a legend reported by historian Yaqut al-Hamawi (d. 1229CE / 626H), there was a hot spring inside that could heal leprosy and other diseases. [Yaqut al-Hamawi, Mu`jam al-Buldan]
Ibn Abi Musa (d. ca. 946CE/334H) was the chief justice of Baghdad, and a man respected for his piety and ascetic lifestyle. He wrote several books on fiqh, including commentaries on some of the works of al-Shaybani, an abridgment of the work his contemporary al-Karkhi, and a work on usul al-fiqh. His full name is Abu `Abdillah Muhammad ibn `Isa). He was found dead, apparently killed by burglars, around the year 334H. [al-Jawahir al-Mudi’ah fi Tabaqat al-Hanafiyyah, 3/295-6 and 4/63]
Yaqut al-Hamawi (historian, belletrist and grammarian, d. 1229CE / 626H) gave the lighthouse’s height as 230 cubits (i.e. 105m), but by his time, the top 20m or so had already collapsed due to an earthquake in 956CE / 345H. So, at the time of Ibn Abi Musa’s fatwa, the lighthouse was likely to have measured around 120m tall, which is approximately the height of a 25 – 30 floor modern building. This is taller than the National Shrine of the Immaculate Conception,in Washington DC (100m), and comparable to the Willis Building (125m, UK’s 36th tallest).
Variations in Sunset Times
So, how much difference does it make for prayer and fasting times Experts today tell us (see here and here) that sunset time gets later by approximately one minute for every 1,500m. That means the sunset delay from the top of the Pharos of Alexandria (150m), and indeed even from the top of today’s Burj Khalifah (828m), would be less than a minute. Some contemporary fatwas advise people atop the Burj to add 2-3 minutes (to the time used by people at ground level), probably to include a safety margin.
Uncertainties at Ground Level Too!
It is worth noting that exact sunset time can vary not only due to altitude, but also due to atmospheric conditions and other factors (see here and here for further details). Many Hanafi jurists therefore advise those who are using calculated sunset times to wait an additional 3 minutes before breaking the fast or performing the Maghrib prayer. Those living at high latitudes (beyond 60 degrees north of the Equator) would be well-advised to allow for a greater error-margin.
The popular IslamicFinder.org website for prayer-time calculation allows you to adjust the settings specify how many minutes to add to the calculated sunset time to produce the listed Maghrib time. But if you do this, make sure you don’t end up praying `Asr too late as a result! While `Asr time ends at sunset, and in light of the uncertainties and variations, it would be advisable to finish `Asr at least 3 minutes before the calculated sunset time, just as it is advised to pray Maghrib only 3 minutes after the calculated time. Of course, if you were inescapably delayed (or even if you were a bit negligent), such that less than three minutes remain before sunset time, you should go ahead and pray immediately; the prayer might still be on time.
A couple of final comments before we close.
One: What happened to the lighthouse? The remnants of the Pharos Lighthouse were removed, and a fort built on its platform in 1480CE / 885H by Mamluk Sultan Qaitbay.
The tallest building in Alexandria today is the San Stefano Grand Plaza measuring in at 135m high; approximately the same height as the original lighthouse!
May these and other current monuments of human achievement be preserved, and serve as sources of benefit to humankind. And may terrorists, and others who seek wanton destruction, be foiled.
Eventually, all material things of this world pass away in the natural course of time. As the famous poetess Khansa’ (d. 645CE/24H) wrote:
All men shall with Fate's hearthstones be assailed,
And lofty homes too one day shall come down.
May we, in these remaining days of Ramadan and thereafter, reflect on reality, and what we are building in the spiritual realm.
Burj Khalifah: By Donaldytong – commons:File:Burj Khalifa.jpg, originally from the author as noted below. Deleted from Commons by admin King of Hearts 5 November 2012., CC BY-SA 3.0, https://en.wikipedia.org/w/index.php?curid=37469604
Airbus: By Laurent ERRERA from L’Union, France – Airbus A320-200 Airbus Industries (AIB) “House colors” F-WWBA – MSN 001, CC BY-SA 2.0, https://commons.wikimedia.org/w/index.php?curid=29541313
Deglet Noor Dates: By M. Dhifallah – M. Dhifallah, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=5008481
Pharos depiction in a medieval Arabic text: From a 15th-century Arabic collectaneous manuscript known as Kitab al-bulhan. – Altered version of http://bodley30.bodley.ox.ac.uk:8180/luna/servlet/detail/ODLodl~23~23~96907~137112:Wonders–the-lighthouse-of-Alexandr, CC BY 4.0, https://commons.wikimedia.org/w/index.php?curid=40875410
Pharos scale comparison: By Emad Victor SHENOUDA, Attribution, https://commons.wikimedia.org/w/index.php?curid=29222659
(Qaitbay) Citadel By ASaber91 – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=63990734
San Stefano Plaza: By Sowr – https://www.flickr.com/photos/87153764@N08/7976239604/, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=35704265
Image of Khansa poetry snippet: screenshot from https://www.aldiwan.net/poem21132.html
Sunset (apparently in Alexandria, Egypt): AhmadAms, https://pixabay.com/photos/sunset-sea-alexandria-egypt-water-2363323/