The Ask An Expert lecture series at the National Mall building is presented every Wednesday at noon. A Museum staff member talks to the public about the history, collection, or personalities related to a specific artifact or exhibition in the Museum.

This artifact is a full-scale model of the Thematic Mapper (TM) instrument first used on Landsat 4, which launched in 1982 and operated until 1993. As the instrument flew over the Earth it "saw" only selected wavelengths of light that, when processed, provided information on the condition of land, water, and vegetation.

How to attend

National Air and Space Museum in Washington, DC

6th St. and Independence Ave SW. Washington, DC 20560