Burntcoat Head, Nova Scotia flow back out. Each day the tides times will change approximately by one hour. The reason why the tides fills and empties the Bay of Fundy each day is due to gravitational pull of the moon and the sun on the earth, as well as earths rotation. Spring tides happen twice a month when the sun, moon, and earth are aligned. During this alignment the tides rise higher than average. Neap tides occur during the first and third quarter moon. During this time the high tides heights are lower than average. At low tide the ocean floor becomes exposed allowing
Orbital station-keeping caused by the oblateness of the Earth is a desirable feature that is part of the mission design but the inclination change caused by the gravitational forces of Sun/Moon is undesirable. For geostationary spacecraft the inclination change caused by the gravitational forces of the Sun & Moon must be counteracted by a rather large expense of fuel, as the inclination should be kept sufficiently small for the spacecraft to be tracked by a non-steerable antenna. For spacecraft in low orbits the effects of atmospheric drag must often be compensated for. For some missions this is needed simply to avoid re-entry;