What is Galileo Galilei?
{{Infobox scientist | name = Galileo Galilei | birth_name = Galileo di Vincenzo Bonaiuti de' Galilei<ref>{{Cite book|url=https://books.google.com/books?id=sFiJFuzRVFQC&pg=PA83|title=Science: The Definitive Visual Guide|publisher=DK Publishing|year=2009|isbn=978-0-7566-6490-9|location=United Kingdom|pages=83|language=en}}</ref> | image = Justus Sustermans - Portrait of Galileo Galilei, 1636.jpg | caption = 1636 portrait by [[Justus Sustermans]] | birth_date = {{birth date|1564|02|15|df=y}}{{sfn|Drake|1978|p=1}} | birth_place = [[Pisa]], [[Duchy of Florence]] | death_date = {{death date and age|1642|01|08|1564|02|15|df=y}} | death_place = [[Arcetri]], [[Grand Duchy of Tuscany]] | field = [[Astronomy]], [[physics]], [[engineering]], [[natural philosophy]], [[mathematics]] | work_institutions = {{ubl|[[University of Pisa]]|[[University of Padua]]}} | patrons = {{plainlist| * [[Cosimo II de Medici]] * [[Federico Cesi]] * [[Ferdinando II de Medici]] * [[Fra Paolo Sarpi]] * [[Francesco Maria del Monte]]}} | education = [[University of Pisa]]<!--no degree--> | academic_advisors = [[Ostilio Ricci da Fermo]] | notable_students = {{ubl|[[Benedetto Castelli]]|[[Mario Guiducci]]|[[Vincenzo Viviani]]}} | known_for = [[Analytical dynamics]], [[heliocentrism]], [[kinematics]], [[observational astronomy]] | signature = [[File:Galileo Galilei Signature 2.svg|130px]]<br>'''Coat of arms'''<br>[[File:Blason de Galilée (Galileo Galilei).svg|100px]] }} {{Physical cosmology|scientists}} '''Galileo Galilei'''{{Efn|{{IPA-it|ɡaliˈlɛːo ɡaliˈlɛi}}}} (15 February 1564{{efn|name=birthdate|[[#Reference-Drake-1978|Drake (1978, p. 1).]] The date of Galileo's birth is given according to the [[Julian calendar]], which was then in force throughout [[Christendom]]. In 1582 it was replaced in Italy and several other Catholic countries with the [[Gregorian calendar]]. Unless otherwise indicated, dates in this article are given according to the Gregorian calendar.}}&nbsp;– 8 January 1642)<ref>{{cite book|author=Evans I.O.|year=1962|title=''Inventors of