500-year-old astrolabe in shipwreck is our earliest known navigation tool

[Buster's Uncle]

500-year-old astrolabe in shipwreck is our earliest known navigation tool
Mashable
Yvette Tan •October 25, 2017






Archeologists have found what they believe to be the oldest astrolabe so far, a 500-year-old navigational tool, among a shipwreck led by Vasco da Gama himself.

The tool, believed to have been from the years 1495-1500, was recovered from the shipwreck of a Portugese explorer ship, which sank during a storm in the Indian Ocean in 1503.

The ship, named the Esmeralda, was part of a fleet led by famed Portuguese explorer Vasco da Gama, who was the first person to sail directly from Europe to India.



Image: wmg/university of warwick/mashable composite


The astrolabe measures 17.5cm in diameter and is less than 2mm thick.

The object was recovered by the Blue Water Recovery team from the bottom of the Indian Ocean back in 2014. But it was only revealed to be an astrolabe after 3D scanning carried out by scientists at the University of Warwick.





The scans showed etches around the edge of the disc, each separated by five degrees.

The markings would have allowed navigators to measure the height of the sun above the horizon at noon to determine their location.

"It's a great privilege to find something so rare, something so historically important, something that will be studied by the archaeological community and fills in a gap," David Mearns, from Blue Water Recovery who led the excavation, told the BBC.

"It was like nothing else we had seen and I immediately knew it was something very important because you could see it had these two emblems on it."


https://www.yahoo.com/news/world-apos-apos-earliest-navigational-081614814.html