Solar loop theory in Riccioli, Astronomia reformata 1665
GB Riccioli's loop theory for the Sun
According to Giovanni Battista Riccioli (Astronomia reformata 1665), the Sun moves westwards along spirals: each spire is ellipse-like. 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 G.B. RICCIOLI, Archive for the History of exact sciences, 79, 4 (2025) DOI: <https://doi.org/10.1007/s00407-024-00343-3>.
Exercise: Enlarge or shrink the loops by changing the speed of the M point.