PLANETS ON UMBRELLA MAKE ASTRONOMY EASY (Aug, 1930)
PLANETS ON UMBRELLA MAKE ASTRONOMY EASY
A new invention for amateur astronomers is said to make self-instruction in the secrets of the skies easy and absorbing. It is a homemade planetarium, which reproduces in miniature the dome of the heavens, showing the planets and constellations mapped out in their proper positions.
The unique contrivance was constructed by a New York City inventor from simple frame parts of metal and wood, while an old umbrella hood served for a dome. It rests on wheels so that it can be moved about without difficulty.
Attached to the frame is a series of bar magnets placed in line with the wooden strut which supports the umbrella dome. If the device is held off the ground by a string, these magnets swing the frame so that the center point of the dome points directly at the North Star. The astronomer in this way obtains his bearings, and is ready to study the stars by verifying their positions according to the carefully labeled map on the inner surface of the umbrella dome.