Science & Discovery in the 7th century

19 sourced entries, 614 CE to 698 CE, oldest first. Also see Science & Discovery across every century or everything else in the 7th century.

• 614First year that didn't happen, according to the phantom time hypothesis.source
• 619The calculation of the Chinese calendar begins to use true motions of the sun and moon, modeled using two offset opposing parabolas.source
• 624The Yiwen Leiju encyclopedia is completed during the Tang dynasty, by the Chinese calligrapher Ouyang Xun.source
• 628Brahmagupta writes the Brāmasphuțasiddhānta, an early, yet very advanced, math book.source
• 632January 27 – An annular eclipse of the sun occurs.source
• 637Queen Seondeok of Silla (Korea) builds an astronomical observatory near Gyeongju (Cheomseongdae), one of the oldest in East Asia.source
• 638The Islamic calendar is introduced by Abu Musa al-Asha'ari. He convinces Umar I to make notes of an era for Muslims.source
• 645The first nengō, derived from the Chinese system of eras (nianhao) begins with the Taika era. (Unclear significance. Needs more explanation as to why this belongs in the list of major events of the year)source
• 646Xuanzang completes his book Great Tang Records on the Western Regions, which later becomes one of the primary sources for the study of medieval Central Asia and India.source
• 647A stone tower astronomical observatory (named Cheomseongdae) at Gyeongju is constructed in Silla (South Korea) around this time.source
• 656September 24 – A total solar eclipse is observable from Easter Island. The next at this location would not occur until July 11, 2010.source
• 6641 May – A solar eclipse affects areas along a line from Central America, through eastern North America, the North Atlantic, Ireland, Great Britain and Germany.source
• 671December 7 – An annular solar eclipse is visible from Tibet to the Maghreb.source
• 675January 5 – In Japan, a platform to observe the stars for astrologers is erected for the first time.source
• 682The first entry is made in the Welsh chronicle Brut y Tywysogion.source
• 683According to Bar Hebraeus, a great comet appeared for eleven days, and there was a severe winter, and the Euphrates froze over, and olive groves and vineyards withered, and beasts, and cattle, and birds came to an end.source
• 684September 7 – A large comet is observed in Japan (it's Japan's oldest observation record of Halley's Comet).source
• 690The approximate date of the earliest known blindfold chess, played by Sa'id ibn Jubayrsource
• 698Princess Taki is sent to Saikū, as a Saiō of the Ise Shrine (Japan).source