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COMMENT PAGE FOR:
  Effect of a giant meteorite impact on Paleoarchean environment and life

 Timwi wrote 2 hours 17 min ago:
 The article perpetuates the widespread misconception that dinosaurs are
 extinct. In reality, (some) dinosaurs survived and evolved into modern
 birds. Everything from penguins to ostriches, hummingbirds to
 albatrosses and woodpeckers to eagles is a dinosaur.
 
 Science communication should do better and clear up this
 misunderstanding.
 
 It would be so much cooler to say that the asteroid killed the
 pterosaurs. Not only is it factually correct, it also opens doors to
 more curiosity. Why do they say pterosaurs instead of dinosaurs? Turns
 out they are separate clades. The pterosaurs, plesiosaurs and mosasaurs
 are all extinct as best as we can tell. The dinosaurs are not.

   bregma wrote 2 hours 8 min ago:
   Dinosaurs are delicious. They taste like chicken.

 dang wrote 9 hours 23 min ago:
 The paper is at [1] . We've adopted its title above.
 
 [1]: https://www.pnas.org/doi/10.1073/pnas.2408721121
 hehehheh wrote 11 hours 32 min ago:
 When is the next one coming? Or what is the probability distributuon
 like?

   patrickthebold wrote 11 hours 17 min ago:
   It's a poisson distribution.

     Arech wrote 5 hours 35 min ago:
     Likely it isn't, because the Solar system today and 3Bln years ago
     are two very different systems.

     nverno wrote 10 hours 49 min ago:
     I imagine it is more of an exponential decay mixed with poisson
     since strikes were far more common back in the day. Also, I'd guess
     an exponential decay in the expected size of impactors over time as
     they've been smashing themselves into pieces.

     dataflow wrote 10 hours 58 min ago:
     Have the data actually been fit a Poisson distribution? Or is this
     is just a guess assuming constant rate and independence?

       glial wrote 10 hours 30 min ago:
       No natural phenomena ever exactly fits any probability
       distribution.

         Q_is_4_Quantum wrote 9 hours 42 min ago:
         except the emission spectra from atoms :)

         dataflow wrote 10 hours 26 min ago:
         Right but I'm saying do we have data showing it's even close?
         (Genuinely asking, I have no idea.)

 1970-01-01 wrote 11 hours 40 min ago:
 Vote for Giant Meteor 2028!
 
 [1]: https://votegiantmeteor.com/
 jeffbee wrote 11 hours 56 min ago:
 The paper also mentions that, at the time, "dinosaur killer"-sized
 objects hit the Earth every 15 million years on average, which must
 have been sort of disruptive.

   kevinkeller wrote 11 hours 50 min ago:
   Likely due to this:
   
   [1]: https://en.wikipedia.org/wiki/Late_Heavy_Bombardment
     jeffbee wrote 11 hours 47 min ago:
     What these authors claimed recently was that prior LHB estimates
     were low by a large factor.
     
     [1]: https://www.nature.com/articles/s41561-021-00835-9
       kevinkeller wrote 11 hours 40 min ago:
       Thanks for the paper link!

 kevinkeller wrote 12 hours 4 min ago:
 I love this type of articles where we can reconstruct what happened so
 long ago just based on careful observations.
 
 Some other instances I've come across:
 
 * The K-Pg extinction event that wiped off dinosaurs had the impact it
 did because the asteroid happened to impact a shallow water region.
 This kicked up a lot of sulfur (in gypsum) that further affected global
 climate: [1] * Earth likely had rings ~466M years ago. We deduced this
 by looking at impact craters from that time period, and seeing that
 they all lie near the equator (accounting for continental drift): [2] *
 Earth's rotation period was probably frozen at 21h, ~600M years ago,
 likely due to interaction between lunar and solar tides. This resonance
 could have been broken by ice ages (!!!). Amazing to think that global
 climate affects earth's rotation:
 
 [1]: https://en.wikipedia.org/wiki/Chicxulub_crater#Effects
 [2]: https://www.sciencedirect.com/science/article/pii/S0012821X240...
 [3]: https://en.wikipedia.org/wiki/Earth%27s_rotation#Resonant_stab...
   Timwi wrote 2 hours 26 min ago:
   The dinosaurs were not “wiped off”, by which I mean they are not
   extinct. This is an extremely widespread misconception that popular
   science articles like this one keep perpetuating. We should do better
   and help people understand that (some) dinosaurs survived and evolved
   into modern birds. Birds are dinosaurs. Dinosaurs are alive today.

     Qem wrote 1 hour 27 min ago:
     When referring to dinosaurs, most people are thinking about
     non-avian, teethed dinosaurs anyway.

   chiefalchemist wrote 10 hours 23 min ago:
   Not to nitpick but the dinosaurs were on already on the way out, the
   asteroid merely finished them off early.
   
   [1]: https://www.theatlantic.com/magazine/archive/2018/09/dinosau...
     Arech wrote 5 hours 39 min ago:
     To the best of my knowledge not everyone agrees to that hypothesis.
     One of the strongest arguments against it is that paleontological
     evidence is always incomplete. Holes in it that are treated in
     favor of the hypothesis are actually smaller or comparable to holes
     that appear just due to incompleteness.

   thangalin wrote 11 hours 13 min ago:
   > reconstruct what happened so long ago just based on careful
   observations.
   
   Me too! My book is filled with them. Like how minerals in lava,
   affected by Earth's magnetic field, lock into place while cooling,
   which provides us with yet another cross-check for radiometric
   dating. See page 23:
   
   [1]: https://impacts.to/downloads/lowres/impacts.pdf
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