In this week's Ask an Expert Live, curator James David will discuss the Galactic Radiation and Background (GRAB) satellite, the world's first successful reconnaisance satellite. Tune in on Facebook Live. 

Every Wednesday at 12:30 p.m. we will go live on the National Air and Space Museum Facebook page with an Ask an Expert talk. We’ll select a different aviation or space topic each week, and a Museum staff member will discuss the history, stories, or personalities related to a specific artifact or exhibition in the Museum. Tune in on Facebook Live each week to join the talk and ask our experts questions.