Moon clouds. The illuminated area of the visible sphere (degree of illumination) is given by formula_3, where formula_4 is the elongation (i.e., the angle between Moon, the observer (on Earth) and the Sun). The gravitational attraction that masses have for one another decreases inversely with the square of the distance of those masses from each other. As a result, the slightly greater attraction that the Moon has for the side of Earth closest to the Moon, as compared to the part of the Earth opposite the Moon, results in tidal forces. Tidal forces affect both the Earth's crust and oceans. The
Jim Berkland G" system: 1) "the gravity gradient, or the forces exacted on the Earth by the gravitational pull of the Sun and the Moon." 2) "Gone Gatos" (missing cats) as indicated by advertisements in several newspapers. 3) "Geyser Gaps", seen as irregularities in the behavior of a geyser in the Napa Valley. Berkland's method has been said to also involve "a hodge-podge of factors". McClellan provides the most detailed description. Berkland starts with two lunar syzygies each month where the Sun, Moon, and Earth are aligned (corresponding to the new Moon and full Moon). He then sets a "seismic window" eight