Geophysics to every area of the Earth sciences. To provide a clearer idea of what constitutes geophysics, this section describes phenomena that are studied in physics and how they relate to the Earth and its surroundings. The gravitational pull of the Moon and Sun give rise to two high tides and two low tides every lunar day, or every 24 hours and 50 minutes. Therefore, there is a gap of 12 hours and 25 minutes between every high tide and between every low tide. Gravitational forces make rocks press down on deeper rocks, increasing their density as the depth increases. Measurements
Sun and Moon (Middle-earth) and 'died': the Sun after this for a while left its course, burning a large part of Arda the world (apparently creating the deserts of Far Harad). In writings which are older than the material from which the published "Silmarillion" was drawn, the Moon was described at one point as being created by Morgoth as a mockery of Arda the world, but this notion was abandoned. In the Round World version of the legendarium, the Sun and the Moon were not the fruit of the Two Trees, but actually preceded the creation of the Trees. Instead, the Trees preserved the