JoinScope on the Skies: Tidal forces
Tidal forces are gravitational and vary between objects; in this case between the Moon and Earth. With an elliptical orbit, the Moon's gravitational influence, its tidal force, on the Earth varies with each apogee and perigee. At perigee, one would expect tides to be higher, which, in fact, was true during the month of October 2006. In this issue of Scope on the Skies, you'll discover the "ins" and "outs" of tidal forces. This article also presents some lesson ideas for use in your middle school science classroom.