Product images of Mariner's astrolabe: obverse
We use a 280gsm fine art paper and premium branded inks to create the perfect reproduction.
Our expertise and use of high-quality materials means that our print colours are independently verified to last between 100 and 200 years.
Read more about our fine art prints.
Manufactured in the UK
All products are printed in the UK, using the latest digital presses and a giclée printmaking process.
We only use premium branded inks, and colours are independently verified to last between 100 and 200 years.
Mariner's astrolabe: obverse
The mariner's astrolabe was a simplified version of an instrument originally developed by Arab astronomers for measuring the height of heavenly bodies above the horizon and came into use in navigation by about 1470. In order to keep it steady when used on board ship, the mariner's version was heavier and had parts of the disc cut away to reduce wind resistance.
The instrument was used to help determine the ship's latitude from the height of the Pole Star or of the sun. At night, the Pole Star was sighted directly through small pinholes in the two vanes mounted on the pivoting alidade or rule. The altitude in degrees was then read off from the scale on the outer edge of the instrument. To measure the Sun's position during the day, the astrolabe was held below the waist and the alidade was adjusted so that a beam of sunlight passed through the top pinhole onto the bottom one.
- Image reference: 8450
- National Maritime Museum, Greenwich, London