Address: 3450 Massachusetts Ave. NW
Washington, DC 20392
When: August 11, 10 a.m. Allow for extra time in advance of the tour because of security checks entering the grounds.
Details: Tour; 25 people per group; pre-registration required
About: The James M. Gilliss library staff will host a tour of its reading room and a visit to a telescope. The library is the largest astronomy library in the United States.
Contact: Sally Bosken, www.usno.navy.mil/USNO/library