MD Gaithersburg Latitude Observatory

This wooden building doesn’t look like much from the outside, but it was actually part of an international cooperative astronomical study of the earth's precession (wobble) on its polar axis of rotation. This Gaithersburg Latitude Observatory was built in 1899 as part of a system of six international latitude observatories; highly remarkable scientific cooperation during a period of terrible international warfare. The observatory and grounds are now designated a National Historic Landmark.

The "Skywatching" programs are held evenings at the Latitude Observatory, and admission is free. Get this on your calendar now: International Observe the Moon Night will be observed on Saturday, October 28, starting at 7pm. The calendar of events is on the museum's Facebook page.

This pagoda-looking thing was used for precisely calibrating the orientation of the telescope. The telescope was aimed through a window in the side of the building (see picture of observatory above) at crosshairs in these windows to ensure that it was correctly oriented, since orientation of the base and mounting of the telescope could drift from day to day. In this way, the measurements at this telescope could reliably be compared with similar measurements at the sites in the cooperating locations internationally, to create findings that could be relied on.