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The '''astrolabe''' is a compact round disc used to observe and calculate the position of [[celestial bodies]], commonly used before the invention of the [[sextant]]. It was the most widely used astronomical instrument of the Islamic and [[Medieval]] periods. The word "astrolabe" comes from the Greek ἀστρολάβος, "astrolabos", which translates as "star-taker".<ref>http://www.oed.com/view/Entry/12253?redirectedFrom=astrolabe#eid Astrolabe, Oxford English Dictionary</ref>

The '''astrolabe''' is a compact round disc used to observe and calculate the position of [[celestial bodies]], commonly used before the invention of the [[sextant]]. It was the most widely used astronomical instrument of the Islamic and [[Medieval]] periods. The word "astrolabe" comes from the Greek ἀστρολάβος, "astrolabos", which translates as "star-taker".<ref>http://www.oed.com/view/Entry/12253?redirectedFrom=astrolabe#eid Astrolabe, Oxford English Dictionary</ref>

Astrolabes usually consist of a flat disc with a sighting rod that could be pivoted to point at the [[Sun]] or bright stars. From the altitude of the Sun or star above the horizon, the local time or position could be estimated. <ref>A presentation for the Man & Technology Course (ES103) @ SUNY Farmingdale,by Gary Agranat & Dave Delligati, Fall 1980.</ref> Astrolabes were usually constructed of light metals, such as [[copper]] or [[zinc]], however elaborate ornamental gold and silver astrolabes were created for wealthy rulers such as [[Pope Alexander VI]] and [[Suleiman the Magnificent]].

Astrolabes usually consist of a flat disc with a sighting rod that could be pivoted to point at the [[Sun]] or bright stars. From the altitude of the Sun or star above the horizon, the local time or position could be estimated.<ref>A presentation for the Man & Technology Course (ES103) @ SUNY Farmingdale,by Gary Agranat & Dave Delligati, Fall 1980.</ref> Astrolabes were usually constructed of light metals, such as [[copper]] or [[zinc]], however elaborate ornamental gold and silver astrolabes were created for wealthy rulers such as [[Pope Alexander VI]] and [[Suleiman the Magnificent]].

There is a common misconception in the appearance of the astrolabe. Most people are more familiar with the mariner's astrolabe, a similar device invented to make reading location easier on the rough seas.<ref>Waters, David Watkin, The Art of Navigation in England in Elizabethan and Early Stuart Times, Yale University Press, 1958</ref>

There is a common misconception in the appearance of the astrolabe. Most people are more familiar with the mariner's astrolabe, a similar device invented to make reading location easier on the rough seas.<ref>Waters, David Watkin, The Art of Navigation in England in Elizabethan and Early Stuart Times, Yale University Press, 1958</ref>