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The Baghdad and Samarkand observatories refined star positions and instruments. The figure is taken from Britannica, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.

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Yes. It sits on the Space shelf, one of 2,600 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.

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The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.

Mondo Knows Facts

Medieval observatories measured the sky for centuries

The Baghdad and Samarkand observatories refined star positions and instruments Islamic astronomers built large instruments such as quadrants and armillary spheres and compiled detailed star catalogues. Ulugh Beg's fifteenth century observatory in Samarkand had a sextant with a radius of about 40 metres. Their star names still appear in modern atlases. It sits in Mondo's space collection, one of 200 facts that each trace back to the reference below.

Where this comes from

Britannica

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Tags: observatories, history, astronomy

Medieval observatories measured the sky for centuries: the short answers

Where does this come from, and can I check it?: The Baghdad and Samarkand observatories refined star positions and instruments. The figure is taken from Britannica, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.
Is this really a space fact?: Yes. It sits on the Space shelf, one of 2,600 sourced facts grouped into space, animals, the human body, history, science and more. Category pages collect every fact in the same field.
What else can I read about it?: The links under the fact point to a quiz, game, puzzle or calculator on the same subject, and the shelf below shows related facts. The wording here is original, and quoted phrases are marked as quotations.