Now unexpected powerful tunes have been discovered in this hum. These new findings could shed light on the source of this enigma.
The planet emanates a constant rumble far below the limits of human hearing, even when the ground isn't shaking from an earthquake. (It does not cause the ringing in the ear linked with tinnitus.) This sound, first discovered a decade ago, is one that only scientific instruments - seismometers - can detect. Researchers call it Earth's hum.
Investigators suspect this murmur could originate from the churning ocean, or perhaps the roiling atmosphere. To find out more, scientists analyzed readings from an exceptionally quiet Earth-listening research station at the Black Forest Observatory in Germany, with supporting data from Japan and China.
Different types
In the past, the oscillations that researchers found made up this hum were "spheroidal" - they basically involved patches of rock moving up and down, albeit near undetectably.
Now oscillations have been discovered making up the hum that, oddly, are shaped roughly like rings. Imagine, if you will, rumbles that twist in circles in rock across the upper echelons of the planet, almost like dozens of lazy hurricanes.
Scientists had actually expected to find these kinds of oscillations, but these new ring-like waves are surprisingly about as powerful as the spheroidal ones are. The expectation was they would be relatively insignificant.
New thinking
This discovery should force researchers to significantly rethink what causes Earth's hum. While the spheroidal oscillations might be caused by forces squeezing down on the planet - say, pressure from ocean or atmospheric waves - the twisting ring-like phenomena might be caused by forces shearing across the world's surface, from the oceans, atmosphere or possibly even the sun.
Future investigations of this part of the hum will prove challenging, as "this is a very small signal that is hard to measure, and the excitation is probably due to multiple interactions in a complex system," said researcher Rudolf Widmer-Schnidrig, a geoscientist at the University of Stuttgart, Germany.
Still, a better understanding of this sound will shed light on how the land, sea and air all interact, he added.
Edição francesa de 1963. Conteúdo:
EP de edição portuguesa de 1960. Conteúdo:
Na época eles chamavam-se "The Beat Brothers" e acompanhavam Tony Sheridan em todas as músicas do álbum, excepto na 1ª, cantada por John Lennon. Programa:
Quando passei no exame da 3ª classe, a prenda que a minha avó materna me deu foi o cartão de sócio do Benfica. Ela era uma "doente" pelo clube e achou ser essa a melhor prenda do mundo, "porque o Benfica é o melhor do mundo" — dizia.
Edição francesa original de 1961. Conteúdo:
Edição portuguesa de 1966. As duas músicas principais, 98.6 e Tell it to my face, são excelentes.
Eu com 22 anos e a Heather com 18 acabados de fazer e sem falar uma palavra de português, enfrentámos durante cerca de 2 anos um clima implacável (quente e húmido), uma guerra estúpida e tremendamente sangrenta, doenças tropicais medonhas e uma disciplina militar intolerável, ministrada por oficiais e sargentos corruptos, incompetentes e desonestos (dos que, mais tarde vieram a fazer o 25 de Abril). Eu fui um simples alferes miliciano, um civil fardado contra a sua vontade e violentado nas suas convicções.
