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India observatory Jantar Mantar 1

Location: Jaipur, Rajasthan

Vrihat Samrat Tantra:




Sundial, Arc type 




The staircase has a gradation scale to tell day in a year, or sun declination, using sun shadow of roof in southern end

 To reduce diffraction of shadow, can use a pin hole device near the hour line side

Site plan 

Astronomicalheritage. 

Curiosityunlocked 

Jantamantar by Barry Perlus

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