Astronomy
T1
Modern radar measures Mars's sidereal period as 686.971 days. The Surya-Siddhanta (~5th c. CE), pre-telescopic, gives a parameter that derives to 687.05 days — accurate to 2 hours in a 23-month orbit. The text gives the same kind of accuracy for every planet in the system, derived from accumulated naked-eye observations stretching back ~1,000 years before the text was compiled.
From the source
“of Mars, two million, two hundred and ninety-six thousand, eight hundred and thirty-two ”
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