Educated in the capital cities of Luoyang and Chang'an , he achieved success as an astronomer , mathematician , seismologist , hydraulic engineer , inventor , geographer , cartographer , ethnographer , artist , poet , philosopher , politician, and literary scholar. Zhang Heng began his career as a minor civil servant in Nanyang.
His uncompromising stance on historical and calendrical issues led to his becoming a controversial figure, preventing him from rising to the status of Grand Historian. His political rivalry with the palace eunuchs during the reign of Emperor Shun r.
Zhang returned home to Nanyang for a short time, before being recalled to serve in the capital once more in He died there a year later, in Zhang applied his extensive knowledge of mechanics and gears in several of his inventions. He invented the world's first water-powered armillary sphere to assist astronomical observation; [1] improved the inflow water clock by adding another tank; [2] and invented the world's first seismoscope , which discerned the cardinal direction of an earthquake km mi away.
In addition to documenting about 2, stars in his extensive star catalog , Zhang also posited theories about the Moon and its relationship to the Sun : specifically, he discussed the Moon's sphericity, its illumination by reflected sunlight on one side and the hidden nature of the other, and the nature of solar and lunar eclipses.
His fu rhapsody and shi poetry were renowned in his time and studied and analyzed by later Chinese writers. Zhang received many posthumous honors for his scholarship and ingenuity; some modern scholars have compared his work in astronomy to that of the Greco-Roman Ptolemy AD 86β Born in the town of Xi'e in Nanyang Commandery north of the modern Nanyang City in Henan province , Zhang Heng came from a distinguished but not affluent family.
