Mark IB Astrograph

The British-invented astrograph helped navigators determine the altitude curves of principal stars by projecting reels of film corresponding to certain latitudes. Suspended above the chart table in medium and heavy American bombers, the astrograph quickly fell out of favor because it was heavy and unreliable.

Caption:
This compact projector used film strips to overlay star curves onto special plotting charts to determine lines of position.
Type: Artifact
Image Date: 2012
Credit: National Air and Space Museum, Smithsonian Institution
Origin: National Air and Space Museum, Smithsonian Institution
Creator: Eric Long
NASM2012-02187
Innovations
Navigation Methods
 
This compact projector used film strips to overlay star curves onto special plotting charts to determine lines of position.