research, he has studied the history of astronomy. In the 1950s, he researched Charles Messier’s life and the Messier Catalog. Gingerich found notes by Messier on two additional Objects, discovered by Pierre Méchain, which he added to the Messier Catalog: M108 (NGC 3556) and M109 (NGC 3992). He investigated the missing Messier Objects, concluding that M91 was probably a comet and that M102 was probably a duplication of M101. The first conclusion was later dismissed as W. C. Williams brought up evidence that M91 is probably NGC 4548, but the second is still open (M102 may be NGC 5866). Gingerich is a recognized authority on both Johannes Kepler and Nicolaus Copernicus, especially in regard to his De revolutionibus orbium coelestium. He is also an expert on Galileo's astronomical observations, and took a leading role in establishing that the watercolor lunar images in a celebrated copy of Galileo's Sidereus nuncius were modern forgeries and not made by Galileo. In 1959, in chapter II of The Sleepwalkers, titled "The System of Copernicus", Arthur Koestler wrote that: "The book that nobody read – the Revolutions of the Heavenly Spheres – was and is an all-time worst-seller." After reading in the Royal Observatory in Edinburgh a thoroughly annotated copy previously owned by Erasmus Reinhold, a prominent sixteenth-century German astronomer who worked in University of Wittenberg shortly after Copernicus' death, Gingerich was inspired to check Koestler's claim and to research who had owned and studied the book's first two editions, published in 1543 and 1566 in Nuremberg and Basel respectively. He discovered, from marginal annotations, that the book was widely read after all. Gingerich also documented where and how the book was censored. Due largely to Gingerich’s work, De revolutionibus has been researched and catalogued better than any other first-edition historical text except for the original Gutenberg Bible. His three-decade-long personal survey of Copernicus’ great book De revolutionibus was recounted in The Book Nobody Read, published in 2004 by Walker & Co. These Copernican researches earned him the Polish government’s Order of Merit in 1981. His most recent books, God's Universe (Harvard, 2006) and God's Planet (Harvard, 2014), deal with the intersection of science and religion. Science and religion Since he is a Christian as well as a historian of science and a cosmologist, Gingerich has been asked several times to comment on matters concerning the interplay between science and faith. One of these, Intelligent