Our Moon Phases application
to see the moon under the words "Current Moon" inside the box just below...
More information about our moon
Formation of Earth-Moon system in the course of solar system formation:
The probability of the moon formation and dynamical effects of moon on obliquity of terrestrial spin
are great. Earth is formed by coagulation between portoplanets that are formed
through runaway growth. Kokubo and Ida (1998,2000, Icarus) showed that portoplanets have
masses of Mars (0.1 Earth mass). The protoplanets become isolated when they acquire such
masses. They, however, start orbital crossing and mutual collisions when nebula gas is depleted
to some extent (Kominami and Ida 2002, Icarus). As a result, Earth is formed. Moon formation
is a by-product of a collision between protoplanets (giant impact hypothesis). Giant impacts
do occur, but they do not necessarily produce a large satellite like the moon. The probability of
forming a large satellite like the moon exists. The moon's gravity precess terrestrial spin axis. The
precession may control evolution of obliquity of Earth (Laskar et al.1993, Nature). The
obliquity should affect the global climate of Earth. Obliquity change of Earth according to tidal
orbital evolution of Moon is apparent.