The metal disc found on the sunken ship turned out to be a navigation device. According to scientists, this is one of the oldest instruments of this type.
The navigation device was found on board the sunken ship "Esmeralda", which was found off the coast of Oman. A metal disk with a diameter of 17.5 centimeters was first described back in 2014, but only now scientists have been able to confirm that the disk really served as an astrolabe. Laser scanning showed that its surface is covered with grooves diverging from the center at intervals of five degrees. The find was reported on the University of Warwick website.
The item is dated 1495-1500. According to experts, it is one of the earliest marine astrolabes known today. These instruments were in use until the 17th century, later they were replaced by more accurate instruments. With the help of sea astrolabes, the latitude at which the ship was at a given moment was determined. Unlike classic astrolabes, sea ones could be used in strong winds.
Disc Model / University of Warwick.
Initially, only two large symbols could be distinguished on the surface of the disc: the coat of arms and the stylized armillary sphere, the heraldic symbol of King Manuel I, who came to power in 1495. Researchers at the University of Warwick scanned the disc with a laser and obtained a 3D model that showed indentations radiating from the hole in the center. These indentations made it possible to determine how high the sun was above the horizon at a certain hour. Also, the purpose of the object is indicated by a fragment of a bracket above the coat of arms - on later devices there are rings for which they were hung.
The head of the search for the ship, David Mearns (David Mearns) believes that the find "pushed" the history of the sea astrolabe several decades into the past. The researcher hopes that in the future it will be possible to find other devices of this period.
Esmeralda set off in 1502, Vasco da Gama's second voyage to India. The ship sank during a violent storm in May 1503.
Natalia Pelezneva
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