March 11 • High Tech Tour • 3:30 p.m.  • NRAO, Green Bank • 304-456-2150 • gb.nrao.edu. Winter hours: Thurs. - Mon. 10 a.m. - 5 p.m. Take a guided tour through parts of NRAO normally off limits to visitors, like lab areas where sensitive receivers are designed and built.  Space is limited to 15 participants per program. The tour lasts approximately one hour; reservations required.