Harford Community College's Black Student Union and Student Activities Office will co-sponsor the college's third annual Martin Luther King Jr. Celebration Thursday, Jan. 31, at 7 p.m. in the college's Chesapeake Theater. The guest speaker will be Dr. Samuel D. Proctor, professor emeritus at Rutgers University. The event is free and open to the public. Information: Barbara Laster, director of student activities and minority affairs, 836-4140 or 879-8920, Ext. 140.