the Google Doodle celebrates the
Prague Astronomical Clock
-- Prague orloj (Czech Pražský orloj) --
whose first recorded mention was October 9 in the year 1410.
"Prague (Praha, CZ) - Karlsplatz (Karlovo nám) Uhrenturm" by Guido Radig
View the amazing functions that this astronomical clock already had -- more than 600 years ago and more than 100 years PRIOR to the solar-centric 1543 Copernican Revolution of Copernicus.
"Schema Orloj en". Licensed under CC BY-SA 3.0 via Commons.