How to make a Sun (Ottomani) Compass

In the previous post, we have seen that the shadow of an object casts a straight line. So what can we do with this info? what use can we make of this? well, based on the line the shadow would have made, we could now make a sun compass. Instead of being indicative of North such as the magnetic compass, the sun compass would be indicative of East-West direction.

Making a Sun compass:

To make a Sun compass, we will need a simple piece of wood. In the piece of wood, we will need a sharp object to cast a shadow. In our case, I have used a nail that has been planted in the middle of the piece of wood.
Prior to make a sun compass, it is important to know which direction is the East-West. For that, you will need to refer to my  previous post and have the points traced on the floor.
The sun compass will use the nail's shadow, but it is important that the compass is inclined at a certain angle, and most important, that we keep the same angle for the later observations. This is why I have used another piece of wood to act as a support, and the same piece of wood would give the same slope if I put one side of the sun compass on top of it.

Sun compass : use reference line that would have been drawn in previous step.

Sun compass - Keep it at a constant angle always to take measurements. Whatever slope you would give it, make sure you keep the same slope always.

Marking the shadow of tip of the nail on the sun compass. From this point, we will draw a line parallel to the one on the ground.

Reference line on Sun compass.

Sun compass - keep always the same side of the sun compass facing towards you for all subsequent measurements

Using Sun compass.

Using the Sun compass: keep the holder flat and rotate right/left to make the shadow touch the reference line.

Sun compass and confirmation with magnetic compass. Direction East-West easily established

Once we align the tip of the shadow with the reference line, we know that we now have the direction East-West

Ottomani compass:
So using a sun compass is nothing really complicated. This sun compass is also called "Ottomani compass", for people who would like to know more about this, they can google this subject and find many vids on You tube for additional information.

Why is a Sun compass important:
If someone was to get lost, the possibility to have a magnetic compass handy in the pocket is very slim, unless you were really prepared when you undertook the trip.

In the movie "The Edge",  Anthony Hopkins gets lost in Alaska and tries to make a magnetic compass using a paper clip and a leaf. Their compass was not of great use and the group ends by turning around in a big circle and gets back to their first spot.
If they would have used a Sun compass instead, their directions could have been easily deducted throughout the day, but, in Alaska, the sun might not show all day long, not like here in Oman where we enjoy long long long sun hours during the year.
Still, I wanted to highlight the importance of having a simple way to navigate, even if the sun was to appear few minutes during the day, one can certainly draw on the soil/sand a reference line using a stick, then get a piece of wood and trace/ carve a parallel line on the wood, use a pen/smaller stick to cast a shadow and create an Ottomani compass that could be used as and when Sun is appearing to know the directions.

Magnetic Vs. Sun compass:
During a recent trip to Houston, I wanted to locate the Qiblah direction inside the airport. As my watch contains a built in magnetic compass, I thought I would just use it. But because the airports are full of metallic armature and electrical cables, it was very interesting to note that in Houston's airport, the North direction was shifted by almost 90 degree!...Fortunately, our gate was close to the window so I just glimpsed outside, used the shadow that the jets were casting on the ground to know exactly my directions, and thus, the Qiblah direction.
So at the end of the day, always trust the Sun and do not always trust the Magnetic compass, as it could be giving you erratic bearing due to metallic/electrical fields interfering with the correct readings.

We should be very thankful to Allah that He put Sun for us to seek directions, and that He Taught us how to make use of it.