|
An
Observatory :
The Jantar Mantar was built in 1710 by Raja Jai Singh II of Jaipur
(1699-1743) in Delhi. This is an observatory consisting of
mason-built astronomical instruments to chart the course of the
heavens. Jai Singh, who was a very scholarly king with a very keen
interest in astronomy and astrology, had other observatories built
too – in Ujjain, Jaipur, Mathura (which no longer survives) and
Varanasi.
The remaining four observatories are at Jaipur, Ujjain, Mathura and
Varanasi. He was disturbed by the finding that the calculated
celestial elements for the Sun, Moon and Planets seemed to disagree
with the observations. These celestial elements were used to
calculate the planetary movements using classical Indian
Astronomical concepts.
The calculating algorithms for celestial object positions had not
been corrected for more than thousand years due to lack of
precessions of earth's axis of rotation. This effect was observed as
far back as the Vedic times ad is called Ayanamasa. Whenever there
was a difference in the calculated and predicted elements due to
precessions, ad-hoc corrections called Bija corrections were applied
so that the calculations and the observations match each other.
These corrections were never organized and classical treatise does
not mention these.
Jayaprakash Yatra Jai Singh felt that corrections were needed to be made
to the existing methods of calculations with precise observations.
Jai Singh constructed a huge observatory of masonry for precise
observation. It is made of brick and plaster and consist of
extruded, interlocked shapes externally. He started with the brass
instruments in his observatory but soon gave them up because of
several inherent flaws. They were too small and their axes were
unstable displacing the center often. He then decided to follow the
style of the renowned Arab astronomer, Prince Ulugh Beg, builder of
the famous 15th century AD observatory at Samarkand, Uzbekistan. The
massive masonry instruments at the observatory at Samarkand suited
Jai Singh's architectural tastes and were far more accurate because
of their size. |
