4 ms·

A bit frustratingly, they mean "geologically instanteously" which is not the same as "instaneous as per human perception". I'm not sure how long rock takes to

A bit frustratingly, they mean "geologically instanteously" which is not the same as "instaneous as per human perception". I'm not sure how long rock takes to cool after an asteroid impact, maybe days, maybe months or years depending on how large of an impact and how cold the surroundings (no atmosphere soooo....) These mechanics are not discussed in the article and are instead just dismissed as "negligible"

wahern 6y ago
Wouldn't molten rock simply flow and flatten? Even if not yet rigid, I'd assume the mountains do effectively form instantaneously (i.e. seconds or minutes), possibly flattening some as they slowly cool. EDIT: The PBS NOVA special "The Day the Dinosaurs Died" describes the mechanics of the Chicxulub impact starting at about the 33 minute mark. It's as instantaneous as one would intuit, given the magnitudes involved: > NARRATOR: The asteroid had punched a hole nearly 20 miles deep, gouging a crater 124 miles wide. Over 40,000 cubic miles of rock were displaced, rising into towering mountains. > JOANNA MORGAN: So, this is an absolutely amazing event, because that happened in less than two minutes, and if you think of it, mountains the size of the Himalayas were formed in seconds. > NARRATOR: As the mountains collapsed, they formed what's known as a "peak ring," found only in the largest of super craters. It's the only peak ring left on Earth; the next nearest is on the moon. https://www.pbs.org/wgbh/nova/video/day-the-dinosaurs-died/ https://www.pbs.org/wgbh/nova/video/day-the-dinosaurs-died/
- sushshshsh 6y ago
  See, now this is an enjoyable fact. It is interesting to think that all of the forces involved in the collision will finish propelling themselves into each other within 2 minutes. One would think that it would be a little bit longer than that, because the transfer of energy between two cars in a car crash is over in a few seconds. But an asteroid colliding with a planetoid seems like it would take longer, given the amount of mass involved and the amount of deceleration that needs to take place (x km/s to 0.0000000 km/s)
  - wahern 6y ago
    Another cool fact: IIRC, the heat was so intense it basically incinerated all flora and fauna across distances that effectively encompassed most of the Americas. The rest of the planet burned more slowly, relatively speaking, as material fell back from outer space and forests burned in a planet-wide conflagration.
    - rraghur 6y ago
      If you liked that, also listen to radiolabs 'dinopocalypse'. it's on YouTube as well. Another interesting fact, some of the ejecta from that impact went as far as the moon!
- Simon_says 6y ago
  They want me to pay $25 to watch something my tax dollars already paid for? Edit: Nevermind, there's a torrent.
  - wahern 6y ago
    Sorry, I didn't realize there was a paywall/geo-block. It works for me in Chrome Incognito after confirming that KQED is my local affiliate, so it might just be regional. (I do donate to KQED, partly so I can access PBS TV on Roku, but account login is just... I don't have the words... so I don't actually login on my computer, and my Roku account link invariably, mysteriously deactivates sometime between the last time I watched something and the next time I want to watch something.)
  - jws 6y ago
    US federal tax dollars no longer fund a significant portion of public broadcasting. Only about 1/7th is federally funded.
    - Simon_says 6y ago
      If 1/7th that doesn't entitle me to watch it, it should be 0.
- JumpCrisscross 6y ago
  > Wouldn't molten rock simply flow and flatten? Flattening is a battle between gravity and a material's binding energy. The Moon's mass permits steeper slopes with similar material. (There are still limits, of course.)
tunesmith 6y ago
That drove me a bit batty. I skimmed the entire article for a time estimate, and am now in a negligibly worse mood for it.
- sushshshsh 6y ago
  Geologically negligible, or? :)

wahern 6y ago

Wouldn't molten rock simply flow and flatten? Even if not yet rigid, I'd assume the mountains do effectively form instantaneously (i.e. seconds or minutes), possibly flattening some as they slowly cool. EDIT: The PBS NOVA special "The Day the Dinosaurs Died" describes the mechanics of the Chicxulub impact starting at about the 33 minute mark. It's as instantaneous as one would intuit, given the magnitudes involved: > NARRATOR: The asteroid had punched a hole nearly 20 miles deep, gouging a crater 124 miles wide. Over 40,000 cubic miles of rock were displaced, rising into towering mountains. > JOANNA MORGAN: So, this is an absolutely amazing event, because that happened in less than two minutes, and if you think of it, mountains the size of the Himalayas were formed in seconds. > NARRATOR: As the mountains collapsed, they formed what's known as a "peak ring," found only in the largest of super craters. It's the only peak ring left on Earth; the next nearest is on the moon. https://www.pbs.org/wgbh/nova/video/day-the-dinosaurs-died/ https://www.pbs.org/wgbh/nova/video/day-the-dinosaurs-died/

sushshshsh 6y ago
See, now this is an enjoyable fact. It is interesting to think that all of the forces involved in the collision will finish propelling themselves into each other within 2 minutes. One would think that it would be a little bit longer than that, because the transfer of energy between two cars in a car crash is over in a few seconds. But an asteroid colliding with a planetoid seems like it would take longer, given the amount of mass involved and the amount of deceleration that needs to take place (x km/s to 0.0000000 km/s)
- wahern 6y ago
  Another cool fact: IIRC, the heat was so intense it basically incinerated all flora and fauna across distances that effectively encompassed most of the Americas. The rest of the planet burned more slowly, relatively speaking, as material fell back from outer space and forests burned in a planet-wide conflagration.
  - rraghur 6y ago
    If you liked that, also listen to radiolabs 'dinopocalypse'. it's on YouTube as well. Another interesting fact, some of the ejecta from that impact went as far as the moon!
Simon_says 6y ago
They want me to pay $25 to watch something my tax dollars already paid for? Edit: Nevermind, there's a torrent.
- wahern 6y ago
  Sorry, I didn't realize there was a paywall/geo-block. It works for me in Chrome Incognito after confirming that KQED is my local affiliate, so it might just be regional. (I do donate to KQED, partly so I can access PBS TV on Roku, but account login is just... I don't have the words... so I don't actually login on my computer, and my Roku account link invariably, mysteriously deactivates sometime between the last time I watched something and the next time I want to watch something.)
- jws 6y ago
  US federal tax dollars no longer fund a significant portion of public broadcasting. Only about 1/7th is federally funded.
  - Simon_says 6y ago
    If 1/7th that doesn't entitle me to watch it, it should be 0.
JumpCrisscross 6y ago
> Wouldn't molten rock simply flow and flatten? Flattening is a battle between gravity and a material's binding energy. The Moon's mass permits steeper slopes with similar material. (There are still limits, of course.)

tunesmith 6y ago

That drove me a bit batty. I skimmed the entire article for a time estimate, and am now in a negligibly worse mood for it.

sushshshsh 6y ago
Geologically negligible, or? :)