Ralph Baldwin was a native of Michigan and a graduate of the University of Michigan. Due to a position as a part-time planetarium lecturer, he developed an interest in lunar topography. During the 1940s, he formulated the principles of current lunar geology: that lunar craters are the result of impact events, not volcanism; that the lack of active lunar erosion means that the craters are very old; that Earth should have been bombarded in the same way; and that there should be impact structures, large and small, still preserved on Earth. His first book "The Face of the Moon" (1949) was the generating force behind modern research in both terrestrial impact craters and lunar surface features. Seldom has a single book had such far-reaching consequences in the progress of science. Although the scientific community was slow to show interest in his ideas, today Baldwin is regarded with awe because he got so much so right so early! Also remarkable is that Baldwin's primary employment was, for many years, as an officer and then president of a manufacturing company, the Oliver Machinery Company. He is a past-president of the Wood Machinery Manufacturers of America.

Deceased 2010 October 23.