Science & Discovery in the 12th century

12 sourced entries, 1100 CE to 1192 CE, oldest first. Also see Science & Discovery across every century or everything else in the 12th century.

• 1100Checkers is invented (approximate date).source
• 1106February 2 – A comet (the Great Comet of 1106) is seen and reported by several civilisations around the world. Lasting for 40 days, the comet grows steadily in brightness until finally fading away.source
• 1120Walcher of Malvern, an English astronomer and mathematician, creates a system of measurement for the Earth using degrees, minutes and seconds of latitude and longitude.source
• 1125A collection of Zen Buddhist koans is compiled, in the Chinese Blue Cliff Record.source
• 1126Adelard of Bath, an English philosopher, translates Muḥammad ibn Mūsā al-Khwārizmī's arithmetic and astronomical works into Latin.source
• 1163The Norwegian Law of Succession is introduced.source
• 1173Algebraic chess notation is first recorded.source
• 1178June 18 – Five monks from Canterbury see what is possibly the Giordano Bruno crater being formed.source
• 1180Alexander Neckam becomes a lecturer in Paris and begins writing De Natura Rerum, one of the earliest Western European works to mention chess (approximate date).source
• 1181Chinese and Japanese astronomers observe what has come to be understood as supernova SN 1181. One of only eight supernovae in the Milky Way observed in recorded history. It appears in the constellation Cassiopeia and is visible in the night sky for about 185 days. The radio source 3C58 was thought to be the remnant from this event, but opinion is shifting towards the recently discovered nebula Pa 30 (ref : Arxiv 2105.12384).source
• 1185May 1 – The Solar eclipse of 1 May 1185, visible across Central America, Northern and Eastern Europe and Kazakhstan, occurs.source
• 1192January 7 – Venus occults Jupiter.source