Alignments to Mecca

From a presentation by Martin Rickman BSc MRICS FRGS, Chartered Land Surveyor, to delegates at the ICCM Conference, Chesford Grange Hotel, Kenilworth on 28 September 2010.

Recently I was surveying a cemetery to produce a new graves layout diagram, and part of the specification for my survey was to check the alignment to Mecca of the Muslim burials area. As there are an ever increasing number of Muslim burials in the UK I thought it would be useful if I were to give some guidance showing how this can be done fairly accurately, and easily, and also how the alignment to Mecca can be established for new cemeteries.

Christian churches are mostly aligned roughly to the east toward the Holy Land, but there are also examples of churches facing north, south and west; and modern Christian burials need no particular alignment. Islam is probably unique in that it has a specific requirement that all mosques and graves be aligned to a precise focal point in Mecca.

Mecca is situated on the western side of Saudi Arabia in the foothills of the Hejaz mountains, and the exact focal point is located at:-

Latitude 21.422508N = 21d 25m 21s N

Longitude 39.826138E = 39d 49m 34s E

Originally these alignments were calculated by using spherical trigonometry to derive a magnetic compass bearing, and this method is still in use today. You would need to remember to add or subtract the magnetic variation, and this information can be found on your local Ordnance Survey map. The Islamic community prints published tables for various locations across specific countries giving the correct magnetic compass alignment to Mecca on certain dates, because the magnetic variation correction value changes over time. More recently, the web-site at www.qibla.com.br will give an alignment to Mecca from any point in the world, but please note that it mistakenly refers to the magnetic variation as compass "declination".

Magnetic compass bearings have more recently been superseded by the Global Positioning System (GPS) which is the newer military and civilian high-tech navigation system, and it is this which enables the sat-nav in your car (or in your hand) to find your position and also your route direction. If you enter the latitude and longitude given above into a GPS or sat-nav (and also some Blackberries, mobile phones, etc.) these can show you the alignment to Mecca. Also, there are some specific GPS devices with the latitude and longitude of Mecca embedded permanently for locating the alignment.

There is a third method of checking or establishing an accurate alignment to Mecca that can easily be done with minimal training and virtually no equipment. Unfortunately this method can only be used on 29 May and 16 July each year - or the day before (or after) if it is cloudy. This method is based on the fact that Mecca lies within the tropics, to the south of the Tropic of Cancer (approx. 23.5 degrees N), and so there are two days of the year when at noon (local time) the sun is directly overhead of Mecca. As Mecca is 39.826138 degrees east of the Greenwich meridian, so the sun is directly over Mecca at 9:21 a.m. Greenwich Mean Time which is 10:21 a.m. British Summer Time.

To undertake this method within the UK, use the following procedure:-

1. Install a (tall) pole in the area where you want to establish or check the Mecca alignment, and ensure that it is vertical with a spirit bubble. Alternatively you could use an existing tall object such as a flag-pole, church spire, lamp-post or telegraph pole, etc.

2. On 29 May or 16 July at precisely 10:21 a.m. insert a stake (or make a mark with chalk or paint) on the line of the middle of the shadow. This method saves you looking into the sun and is therefore much safer! The line from the stake to the pole is the alignment to Mecca.

3. If, having marked the alignment, you need to transfer it elsewhere, use a magnetic compass to measure the bearing of the alignment from the stake to the pole. You can then stand anywhere in the cemetery and repeat this bearing to establish a line parallel to the original alignment. This has nothing to do with the compass bearing method I have described above, because here we are using the compass only as a convenient method of transferring the alignment, and we can ignore the magnetic variation as it will be the same for both parallel lines.

4. This process is a sundial in reverse – with a sundial we use known alignments to tell the time, however here we are using a known time to determine the alignment.

In doing my research for this paper I tried to quantify the acceptable accuracy for Mecca alignments, but was unsuccessful. In Islam the mosques and graves are aligned by the Imam, or priest, and he is not a surveyor or navigator. The grave alignments I have seen being established were done by an Imam with a small hand-held compass, and I would guess that these were aligned correctly within a degree or two. When I worked at Yanbu in Saudi Arabia, we could see that some adjacent mosques were not constructed exactly parallel, but it didn’t seem to matter that the alignments were not perfect. So in my opinion, it is not absolutely critical that alignments be exact, however, I think it would be worth spending some time and money getting the alignment fairly accurate if you are setting-out a new cemetery, or starting a new section of an existing cemetery to be reserved specifically for Muslim burials.

Normally, a Muslim grave should be perpendicular (not parallel) to the alignment with the body "asleep" on the right side looking towards Mecca (pictured above), but please check with the Imam and the Muslim community for specific local customs as there may be some differences in traditions between the different sects of Islam.

As a final word I would say it is not critical to establish absolutely perfect alignments to Mecca but we should all use our best efforts out of respect for the customs and traditions of all the various faiths that employ our services