Gif Sun on major trunk - Riccioli Astronomia reformata 1665
GB Riccioli's loop theory for the Sun
According to Giovanni Battista Riccioli (Astronomia reformata 1665), the Sun goes on spire after spire through the following points L, M, N, O starting from Cancer. The sun apogee is in G and Sun moves westwards along spirals: each spire is ellipse-like. Riccioli measures the solar distance to the cone’s axis DE (coincident with the horizon). The trunk QRIG contains the solar spiral during the boreal motion, the trunk QRSh those of the austral one. For the eastwards motion is apparent, the only true motion is westwards. Besides, the spiral-like motion has the kind of motion of all the planets, too. The point K traces Sun’s spirals on the truncated cone’s surface. Distances are enlarged here to be the image clear. Vistas are from outside (a) to inside (b) the major section of the truncated cone. See also the motion of point M in the transversal
section of the major truncated cones’s at URL: <https://www.geogebra.org/m/vtgsn37t>.
See F. Marcacci, P. Bussotti, HOW TO USE KEPLER’S FIRST AND SECOND LAWS IN A GEO-HELIOCENTRIC SYSTEM? ASK TO G.B. RICCIOLI, "Archive for the History of Exact Sciences", forthcoming.