In 2013, the wreck of a Portuguese ship belonging to Vasco da Gama's second expedition to India in 1502 was discovered off the coast of Oman.
In 2016 the ship was finally identified as one of those captained by the Sodré brothers, and we already told then how it was the oldest found of the age of discoveries . Now, the study of some of the remains extracted from the ship holds new surprises.
First of all, the ship's bell, whose date 1498 was already visible at the time of discovery, and which has turned out to be the oldest of its kind in the world.
But perhaps more interesting is a piece of nautical astrolabe, whose date of manufacture has been estimated between 1496 and 1501, which also makes it the oldest of its kind.
Do not confuse the nautical astrolabe with the astrolabe proper, as they are slightly different, the nautical being more of a kind of inclinometer . The oldest astrolabe was made by the Persian astronomer Nastulus in the year 927 and is kept in the National Museum of Kuwait.
But the find is important because nautical astrolabes are rare pieces in the archaeological record. Only 104 of them have appeared so far.
Their first documented use dates back to 1481, in a Portuguese expedition to the West African coast, and from then on they would be common in all the important explorations of the late fifteenth century.
It is also the only piece whose origin is verifiable, since it bears the royal coat of arms of Portugal.
The disk, 175 millimeters in diameter and weighing 344 grams, is a transitional instrument between the classic planispheric astrolabe and the open-wheel astrolabe that came into use shortly before 1517.
The analysis of the object was carried out by experts from the University of Warwick and Texas A&M University, finding 18 scale marks spaced at uniform intervals along the disk, not visible to the naked eye, which allowed it to be identified as a nautical astrolabe. .
Previously the oldest official ship's bell was that of the Mary Rose (sunk in 1545), which is dated 1509. The oldest nautical astrolabe was that of the Bom Jesus, another Portuguese ship sunk in 1533 off the coast of Namibia.