The United Nations General Assembly during its 74th Plenary Meeting proclaimed 2019 as the International Year of the Periodic Table of Chemical Elements (IYPT 2019) on 20 December 2017.

1869 is considered as the year of discovery of the Periodic System by the Russian scientist, Dmitri Mendeleev. The IYPT 2019 also commemorates the 150th anniversary of the establishment of the Periodic Table of Chemical Elements. The IYPT aims to recognize the importance of the Periodic Table of Chemical Elements as one of the most important and influential achievements in modern science reflecting the essence not only of chemistry, but also of physics, biology and other basic sciences disciplines.

http://www.unesco.org/new/en/brasilia/about-this-office/prizes-and-celebrations/2019-international-year-of-the-periodic-table-of-chemical-elements

https://web.lemoyne.edu/giunta/EA/MENDELEEVann.HTML