Science & Discovery in the 9th century

11 sourced entries, 800 CE to 863 CE, oldest first. Also see Science & Discovery across every century or everything else in the 9th century.

• 800The ci, a new type of lyric poetry with irregular lines, is set to a melody during the Tang Dynasty (approximate date).source
• 812Charlemagne issues the Capitulare de villis, concerning the rights of a feudal landholder and the services owed by his dependents. It also contains the names of some 89 plants, of which most are used medically.source
• 813The Baghdad School of Astronomy is opened by al-Ma'mun.source
• 837April 10 – Halley's Comet passes approximately 5 million km from Earth, its closest ever approach.source
• 841December 17 – Comet X/841 Y1 is first sighted in Chang'an by the Japanese monk Ennin.source
• 842February 13 – Last reported sighting of the comet X/841 Y1 according to the Annals of Fontenelle.source
• 850Coffee is discovered (according to legend) by the Ethiopian goatherder Kaldi in East Africa, who notices that his goats become energetic after chewing the red berries from certain wild bushes (approximate date).source
• 853Tuan Ch'eng-Shih, Chinese author and scholar during the Tang Dynasty, publishes Miscellaneous Offerings from Yu-yang.source
• 861Al-Mutawakkil (r. 847–861) orders the construction of a Nilometer on Rhoda Island in central Cairo, supervised by the Persian astronomer Ahmad ibn Muhammad ibn Kathir al-Farghani.source
• 862The first written record (according to the Primary Chronicle) is made of the towns of Belozersk and Murom (Northern Russia).source
• 863The first written record is made of Smolensk (according to the Primary Chronicle).source