2344: 26-Second Pulse

2020-08-11T10:50:01Z

Nuggets: Add link to clock drift correction paper.

{{comic
| number = 2344
| date = August 10, 2020
| title = 26-Second Pulse
| image = 26_second_pulse.png
| titletext = There are some papers arguing that there's a volcanic component, but I personally think they're just feeling guilty and trying to cover the trail.
}}

==Explanation==

In this comic strip, [[Science Girl]] is teaching a class on geology, and explaining some of the non-earthquake signals that seismometers detect. She describes [https://phys.org/news/2011-01-seismometer-noise-south-atlantic-storms.html a mysterious signal that repeats with a 26-second period].
Scientists have exploited this signal to [https://www.researchgate.net/publication/320126150_Assessing_the_short-term_clock_drift_of_early_broadband_stations_with_burst_events_of_the_26_s_persistent_and_localized_microseism correct for clock drift] in historic seismic records.

[[Science Girl]] initially provides a plausible explanation (some kind of natural wave pattern on the coastline of the {{w|Gulf of Guinea}}).
However, she quickly takes a turn for the dramatic when she claims that it might be a giant, murdered by seismologists, whose heart still beats. This is a reference to Edgar Allan Poe's short story ''{{w|The Tell-Tale Heart}}'', in which the main character murders his landlord and hides him beneath the floorboards, and then hears (or believes he hears) his victim's heart continuing to beat; the noise eventually drives the man to confess his guilt to visiting police officers. (The narrator of ''The Tell-Tale Heart'' never uses that phrase in the story; he calls it a ''hideous'' heart.) "The Tell-Tale Heart" was previously referenced in [[740: The Tell-Tale Beat]].

Normal human hearts beat much more rapidly than once every 26 seconds, but [https://www.answers.com/Q/What_animal_has_slowest_heart_rate large animals and hibernating animals] may have much slower heart rates (which would include a giant at the bottom of the ocean).

The title text gives an alternate explanation for the seismic activity: [https://academic.oup.com/gji/article/194/1/362/2006108 volcanic activity], but Science Girl continues to believe in the giant story.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

:[Science Girl is standing in the front of a whiteboard with a pointer. Ponytail, Hairy, and Megan are sitting at desks.]
:Science Girl: When everything is still, seismometers pick up faint tremors we call seismic noise.
:Science Girl: Most of it is from ocean waves, cars, etc. But there's also a mysterious 26-second pulse.

:[Close up on Science Girl, pointing to a map of the world. Africa is in view, and a star is drawn within the country of Ghana.]
:Science Girl: We've triangulated the source to somewhere in the Gulf of Guinea.
:Science Girl: It comes and goes with the seasons, but it's been there since at least the 1980s. It's so regular we use it to sync up seismometers.

:[Science Girl is shown in profile, with the board behind her.]
:Off-panel voice: What causes it?
:Science Girl: Not sure. The most popular theory is that storm-driven waves set up some kind of resonance with the coast.

:[Science Girl has leaned her stick on the board's tray. She has raised her clenched fists.]
:Science Girl: Another theory is that long ago, seismologists murdered a giant and buried the body at sea.
:Science Girl: Now we are haunted by the beating of its telltale heart!
:Science Girl: Could be either.
:Science Girl: Further research is needed.

{{comic discussion}}
[[Category:Comics featuring Science Girl]]
[[Category:Comics featuring Hairy]]
[[Category:Comics featuring Ponytail]]
[[Category:Comics featuring Megan]]
[[Category:Geology]]
[[Category:Fiction]]

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2344: 26-Second Pulse