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The Jantar Mantar in Jaipur, India, completed in 1734 for the Rajput king Sawai Jai Singh II, is a collection of giant stone instruments for measuring the sky with the naked eye. Its largest sundial stands about 27 metres high.

Jaipur, 1734

ArchitectureScienceHistory

The story behind the card

Jai Singh, who founded the city of Jaipur in 1727, wanted more accurate astronomical tables for calendars and eclipse predictions, and built five observatories across northern India: at Delhi, Jaipur, Ujjain, Mathura and Varanasi. Jaipur's is the largest and best preserved. The name is usually explained as 'calculating instrument'. Its nineteen main instruments measure time, the height of the Sun and the positions of stars by shadows and sightlines. On the giant sundial, the Samrat Yantra, the shadow moves about six centimetres a minute, which lets it tell local time to within about two seconds. UNESCO added the observatory to its World Heritage List in 2010.

Türkçe oku
Hindistan'ın Jaipur kentindeki Jantar Mantar, Racput hükümdarı II. Sawai Jai Singh için 1734'te tamamlanmış bir gözlemevidir; gökyüzünü çıplak gözle ölçmeye yarayan dev taş aletlerden oluşur. En büyük güneş saatinin yüksekliği 27 metreyi bulur.
Jaipur, 1734

1727'de Jaipur kentini kuran Jai Singh, takvimler ve tutulma hesapları için daha doğru astronomi tabloları istiyordu. Bu amaçla Kuzey Hindistan'da beş gözlemevi yaptırdı: Delhi, Jaipur, Ujjain, Mathura ve Varanasi'de. Bunların en büyüğü ve en iyi korunanı Jaipur'dakidir. Adı genellikle “hesap aleti” diye açıklanır. On dokuz ana alet, gölgeler ve nişan çizgileri yardımıyla zamanı, Güneş'in yüksekliğini ve yıldızların konumunu ölçer. Samrat Yantra adlı dev güneş saatinde gölge dakikada altı santimetre kadar ilerler; bu sayede yerel saat iki saniyeye yakın bir hassasiyetle okunabilir. UNESCO, gözlemevini 2010'da Dünya Mirası Listesi'ne aldı.

Sources and further reading

Background reading: Jantar Mantar, Jaipur
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