Earth’s 26-Second Pulse Still Baffles Scientists in 2025

SCIENCE

By Aniket Chakraborty June 4, 2025 Arrow

First recorded in the 1960s, this quiet tremor has echoed unchanged for decades.

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Known as a "microseism", it was initially traced to the equatorial Atlantic Ocean.

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In 2005, digital seismic data revived the mystery and pointed to the Gulf of Guinea.

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One theory blames powerful ocean waves striking the continental shelf.

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Another suspects underwater volcanic activity near São Tomé Island.

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Despite years of study, there’s still no definitive answer to what causes it.

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Some scientists have deprioritized it—yet it continues, steady and unexplained.

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Every 26 seconds, Earth ticks like a geologic metronome in the deep.

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A silent heartbeat beneath the waves—unresolved, uncanny, and still counting.

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