The Earth has to be at the gym in 26 seconds

Why is Earth pulsating every 26 seconds, and why can’t scientists explain it after 60 years? This is an enigma wrapped in a periodically predictable mystery motion. It could be a harmonic phenomenon, a regular seismic chirp caused by the sun’s energy, or a beacon drawing scientists to its source to begin a treasure hunt.

In the early 1960s, a geologist named Jack Oliver first documented the pulse, also known as a "microseism," according to Discover. Oliver, who worked at Columbia University's Lamont-Doherty Geological Observatory at the time, heard the noise, but didn't have the advanced instruments seismologists have now at his disposal.

Since then, scientists have spent a lot of time listening to the pulse and even finding out where it comes from: “a part of the Gulf of Guinea called the Bight of Bonny,” Discover says.