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The Earth Is Pulsating Every 26 Seconds, and Seismologists Don't Agree Why

discovermagazine.com

11–20 of 112 posts

Re: The Earth Is Pulsating Every 26 Seconds, and Seismologists Don't Agree Why

#13
post #5

Why haven’t I heard about this before? This seems too important a detail for my school textbooks to have left out and for popular culture to lack any references to it whatsoever. What am I missing?

> But nearly 60 years after the pulse was first observed, no one has managed to figure it out. That may be because, as far as seismologists are concerned, it’s just not really a priority. “There are certain things that we concentrate on in seismology,” explains Wiens. “We want to determine the structure beneath the continents, things like that. This is just a little bit outside what we would typically study … [since] it doesn’t have anything to do with understanding the deep structure of the Earth.”

> That doesn’t mean it’s not worth studying, Ritzwoller adds.

The same reason it's not important enough to finish the article ;)

Re: The Earth Is Pulsating Every 26 Seconds, and Seismologists Don't Agree Why

#14
post #5

Why haven’t I heard about this before? This seems too important a detail for my school textbooks to have left out and for popular culture to lack any references to it whatsoever. What am I missing?

> Why haven’t I heard about this before?

It's probably just part of the "Earth's hum", which is waves.

(Don't confuse this with the world wide paranormal hum people claim to hear)

You probably should have learned of the hum at school, if you did, you'd have probably forgotten. As a 10 year old you'd either find it amazing and think of it forever or just forget.

It would be interesting to rank it on the importance level though. Or, it'd be interesting to work out how you could rank it. What are important things to know... in order... for personality types.

Re: The Earth Is Pulsating Every 26 Seconds, and Seismologists Don't Agree Why

#15
post #5

Why haven’t I heard about this before? This seems too important a detail for my school textbooks to have left out and for popular culture to lack any references to it whatsoever. What am I missing?

> For popular culture to lack any references to it whatsoever As the first paragraph of the article has mentioned, at least xkcd has a reference [0]. [0] https://xkcd.com/2344/

Is there really any subject on which there is no xkcd? They are the Simpsons of web cartoons.

Re: The Earth Is Pulsating Every 26 Seconds, and Seismologists Don't Agree Why

#16
Never heard of this, so I had to do some digging. My money is on this being an ocean wave phenomenon.

The Gulf of Guinea, specifically the Bight of Bonny, is up to ~20,000ft deep. Average ocean waves have a period less than 15s and the average ocean depth of the Atlantic is ~11,000ft. Oddly similar ratios! So it's plausible this 26s wave period is caused by the increase in depth [0]. The abnormally large seismic amplitude can be similarly attributed, as pressure patterns conditionally form along the bottom of the ocean (in either direction) due to combined features of both the wave and the ocean bottom topography. [1]

[0] https://en.wikipedia.org/wiki/Wind_wave#Physics_of_waves

[1] https://en.wikipedia.org/wiki/Microseism#Generation_of_secon...

Re: The Earth Is Pulsating Every 26 Seconds, and Seismologists Don't Agree Why

#17
post #5

Why haven’t I heard about this before? This seems too important a detail for my school textbooks to have left out and for popular culture to lack any references to it whatsoever. What am I missing?

> Why haven’t I heard about this before? It's probably just part of the "Earth's hum", which is waves. (Don't confuse this with the world wide paranormal hum people claim to hear) You probably should have learned of the hum at school, if you did, you'd have probably forgotten. As a 10 year old you'd either find it amazing and think of it forever or just forget. It would be interesting to rank it on the importance lev…

Huh, I feel like that’s something I’d remember learning.

Did many other people here learn that?

Re: The Earth Is Pulsating Every 26 Seconds, and Seismologists Don't Agree Why

#20

That's CPU cycles in the computer built to discover the the ultimate question of life, the universe and everything.

Rather slow clock rate in our perception, but not that bad if you're computing for millions of years.
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