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Comment by janmo | Hacker News Reader

https://mobile.twitter.com/FirstName__Last/status/1482259505... I am no expert but this looks huge, perhaps something the size of the Krakatoa eruption. https://en.wikipedia.org/wiki/1883_eruption_of_Krakatoa

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Much smaller than Krakatoa so far. We'll have to see where it comes out on the VEI scale though. Krakatoa was really big, so I think it's pretty unlikely we will get close to that on this one.

The Tsunami they are guessing probably came from an earthquake or underwater landslide caused by the eruption, but the eruption doesn't really need to be huge to cause those. It'll be interesting to see once the eruption stops (if it's a landslide, you can usually see a crescent shaped formation on the volcano, although it may be underwater).

From the Krakatoa page:

"The third explosion has been reported as the loudest sound heard in historic times. The loudness of the blast heard 160 km (100 mi) from the volcano has been calculated to have been 180 dB. Each explosion was accompanied by tsunamis estimated to have been over 30 metres (98 feet) high in places. ...The energy released from the explosion has been estimated to be equal to about 200 megatonnes of TNT, roughly four times as powerful as the Tsar Bomba"

The terminator in this video provides a good sense of time elapsed.

Wow I'd never have known the line between day and night ever had a name, before you used that word! :)

In some alternate universe 1984's "The Terminator" is a movie with a similar plot to "Pitch Black" in our universe (yes I know it's an eclipse in "Pitch Black").

The Ecliptic Terminator - "I'll be back!"

And you can be pretty sure it will be back, inevitably.

That seems unlikely, since the magnitude was only 4.0. The relation between magnitude and actual impact is complex, but big ones tend to be 6+ and really big ones 8 or even 9.

The current magnitude estimate from the USGS is 5.8, with the caveat that, "...this event is calculated using techniques calibrated for earthquakes. The current magnitude is only a preliminary estimate for this volcanic event." [1]

  1: https://earthquake.usgs.gov/earthquakes/eventpage/pt22015050/executive

What is the magnitude scale for volcanoes vs earthquakes? The tsnumai.gov site says this is magnitude 1.0 but without units or type. So I wonder if it's a tsunami potential specific scale?

I think the 1.0 magnitude is there as a placeholder. The advisories say to ignore it:

>Please disregard earthquake parameters

What are you basing your comparison of the two on I wonder?

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