Deep water: area where surface waves are not influenced by the sea-bottom.

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TDS-1 payloads include instruments to track ships and monitor the sea surface for freak waves, and even a self-destruct "sail" that will pull the spacecraft out of the sky at the end of its mission.

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Astroseismology is performed when scientists examine the sound waves generated beneath the surface of the star to determine its size.

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When placed on a flat surface, the stack redirects the waves such that reflected waves are exactly as they would be if the stack were not there at all.

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According to Teruyuki Kato, the project's leader, this arrangement can measure a buoy's vertical motion with an accuracy of a few centimetres, which will pick up dangerous tsunamis in the open ocean where they are mere ripples on the surface (they rear up into killer waves only when they reach the shallows).

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If there is any oil suspended underwater, such high waves would bring it to the surface - but it is likely then to be diluted, she says.

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What is needed are specific detectors that take advantage of the fact that tsunamis are felt throughout the ocean's depths, unlike wind-generated waves, which affect only its surface.

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In the sun, the surface of the sea flashes with white-capped waves.

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