The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 22, 2002
Filed:
Jan. 03, 2000
W. Daniel Hillis, Toluca Lake, CA (US);
The Long Now Foundation, Sausalito, CA (US);
Abstract
In the astrolabe herein, both the rete and the plate rotate, although around different centers. The stars are drawn onto the plate, and the coordinate system is represented by the rete. In contrast to the conventional astrolabe, where the stars and the coordinate system are projected onto a plane parallel with the earth's equator, the improved astrolabe projects stars and the coordinate system using a stereographic projection onto a plane parallel with the plane of the ecliptic. This projection puts the celestial pole at the center of the rete, and the line orthogonal to the ecliptic is projected onto the center of the plate, which points about 23.5 degrees off the earth's axis. As with a conventional astrolabe, the rete is rotated to represent the sidereal motion of the stars. In contrast to the conventional astrolabe, the plate may also be rotated to represent the precession of the earth's axis. Thus, by the combined rotations of the rete and plate the correct position of the stars for any time may be indicated. Although the embodiment described here places the stars on the plate and the coordinate system on the rete, it will be apparent to anyone skilled in the art of astrolabes that the arrangement can easily be reversed, putting stars on the rete and the coordinate system on the plate.