Weird Patent of the Day
Spherical star chart with indicator
A spherical star chart with an indicator, based on the fact that a majority of the celestial objects maintain a constant angular relationship with each other. Because those objects are so far from the center of the earth, parallax from observations made on the surface is negligible.
Source: United States Patent and Trademark Office, www.uspto.gov. Official PDF: USPTO patent PDF. Also at Google Patents. The drawing on this page is a reduced copy of the official figure; see the original drawing.
