Constellations Thesis Book by Nesrin Zidan

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• Kamal: An Arabian navigational device
used to estimate latitude from the North
Star. With the top edge aligned with the
North Star and the bottom edge aligned
with the horizon, sailors would hold a
rectangular plate in front of their faces.
They could establish the ship’s latitude by
measuring the distance between the plate
and the tip of their noses using a thread
fastened to the plate’s center (History of
Navigation at Sea: From stars to the modern-day
GPS, 2019).
• Sextant: Thomas Godfrey in America
and John Hadley in England separately
developed the sextant in the 18th century.
The sextant is a double-reflecting navigational
tool. It’s employed in celestial navigation
to determine latitude and longitude
and to find the angle between the horizon
and a celestial body, such as the Sun,
the Moon, or a star (What is a Mariner’s
Astrolabe?). The tool consists of a circle
with a degree-marked arc and a revolving
moveable radial arm in the middle. The
horizon is aligned with a telescope that is
rigidly attached to the structure. The sextant’s
arc spans 60°, which is one-sixth of
a circle; thus its name (Britannica, 2019).
Fig. 3.3. A Kamal and how to weild it
Fig. 3.4. A typical Sextant