1001 Space Earth Earth Rocks and Minerals Landscape Sea Weather and Climate Natural Disasters Resources Nature History Human World Science and Technology

Choose a Page:How long has there been life in th...How much of the Earth is covered b...Why does seawater taste salty?Is the ocean floor flat?What causes waves?What is an iceberg?Are tidal waves caused by the tides?What are ocean currents?How has the ocean bed been measured?How does the sea affect the climate?How do coral reefs form?Are there currents at great depths?*Why does the tide come in and go out?* Why does the tide come in and go out? As the Moon and the Earth swing round each other, ocean water is thrown to the side of the Earth away from the Moon. At the same time, the moon's gravity attracts water to the side facing the Moon, resulting in two periods of high tide every 24 hours. The Moon is relatively close to the Earth!   Previous: Back Book: 1001 Section: Earth Chapter: Sea