Michael A’Hearn ’61, the principal investigator on NASA’s Deep Impact Project, spoke with students in professor Paul Haines’s “Introduction to Modern Physics” class on April 11 in Higgins Hall 310. On the previous evening, A’Hearn spoke to a capacity crowd as part of the Master Class: Alumni in Residence series. Michael Naughton, interim associate vice president for research, moderated the conversation with A’Hearn, who told students and faculty about his career in physics and his work on the Deep Impact Project. In July 2005 he led a team of physicists and engineers that sent a rocket to the comet Tempel 1, some 83 million miles from Earth—the first time that humans had touched a comet in space. The group’s goal was to learn about the formation of the solar system and the composition of comets. To read a profile about A’Hearn, Distinguished University Professor in the University of Maryland’s astronomy department, see “Mission control” in Boston College Magazine. A’Hearn’s visit to Boston College was sponsored by the magazine and cosponsored by the physics department.