Medieval Astrolabe

Widely used in medieval times, an astrolabe is a disc-shaped device used for finding latitude and measuring time by sighting on stars, like a sextant.

introduction

The stars and nebulae visible to our unaided eyes all lie within our own galaxy, the Milky way. Binoculars and small telescopes expand our horizons to other galaxies millions of light-years beyond, while modern instruments have stretched our visual limits to a few hundred thousand years from the Big Bang, the cosmic eruption that marked the birth of space and time, some 13.7 billion years ago.

Dating the big bang has been one of the great achievements of modern cosmology, but along with this

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