On September 9, the Acton Memorial Library’s gallery artist series departed from its usual earthly fare and welcomed Acton resident Marsha Wilcox to show and describe her stunning images of nebulae and galaxies, the current exhibit in the library’s gallery space. Nebulae are interstellar clouds of dust and gas that either emit or reflect light, and galaxies are clusters of stars. In either case, light from these entities travels across vast distances through the universe, to be captured by Wilcox’s telescope. She then processes the captured data into images that straddle the divide between art and science. As she explained…