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I'm starting to wonder if a somewhat similar event could have occurred ~66 million years ago and triggered a series of events leading to the extinction of dinos

by hasenj 12y ago

I'm starting to wonder if a somewhat similar event could have occurred ~66 million years ago and triggered a series of events leading to the extinction of dinosaurs.

Thrymr 12y ago
That is basically the Nemesis hypothesis: http://en.wikipedia.org/wiki/Nemesis_%28hypothetical_star%29 http://en.wikipedia.org/wiki/Nemesis_%28hypothetical_star%29
Sanddancer 12y ago
That's the basis of the Nemesis hypothesis [1]; that supposedly there's a star that roughly orbits the sun and causes havoc every few miillion years. However, it's been pretty much debunked at this point [1]http://en.wikipedia.org/wiki/Nemesis_%28hypothetical_star%29 http://en.wikipedia.org/wiki/Nemesis_%28hypothetical_star%29
- hasenj 12y ago
  Well it doesn't have to be orbiting the sun and causing this periodically. It could've been a one time event.
- tomphoolery 12y ago
  Was gonna come in here to ask...will this explain Nemesis as not a recurring event but rather a one-time event caused by that trailing brown dwarf (or the star itself) flinging comets all over the place. It would also explain a lot of other crater-rich surfaces dating back to that time...
  - vidarh 12y ago
    Not without time travel... This was only 70 thousand years ago.
  - iwwr 12y ago
    If that's true it'd be hard to identify the responsible star since in a few million years it would be thousands of light years away and difficult to measure precise kinematics of it.
  - logfromblammo 12y ago
    Given the distances involved, anything that may have had its orbit altered by this event is extremely unlikely to have struck any solid surface in our system already. It may, however, lead to some additional bombardment a few million years from now. By that time, we might have computers of sufficient power working from an astronomical catalog of sufficient completeness to reverse-propagate the catalog far enough to actually blame the passing stars for kicking out comets in our direction.
- mangeletti 12y ago
  The Nemesis Hypothesis hasn't been debunked.
  - dragonwriter 12y ago
    > The Nemesis Hypothesis hasn't been debunked. I rather thought that Nemesis had become a fairly untenable hypothesis in light of the the facts that: (1) Insofar as there is a periodicity to extinctions to explain (what Nemesis was posited to explain), more recent analysis has shown that it is too consistent for any plausible orbit for Nemesis, and (2) A sensitive enough survey to detect stars (including brown dwarfs) within the radius of Earth in which Nemesis would have to exist has been conducted and failed to detect any such star.
    - mangeletti 12y ago
      I'm not sure I understood point #1. Do you mean that the periodicity is too consistent to support the theory of an orbiting body, because an orbiting body would have a less consistent orbit? If so, that's very interesting. Pertaining point #2, I'm not very confident in any empirical data observed at this point in human evolution. It's not to say that scientists aren't working very hard to learn things, but moments like http://www.theguardian.com/science/2015/feb/26/found-a-black-hole-12-billion-times-the-size-of-the-sun http://www.theguardian.com/science/2015/feb/26/found-a-black... tell me that we're going to go through many more "we're absolutely sure / wait, we were wrong" moments, especially when pertaining astronomy and ontology, both fields with many more unknowns than true facts.
mathattack 12y ago
The current consensus is a Manhattan-sized asteroid. [0] The science behind this is pretty strong. What's come open for question is how fast this happened. A new theory posits that the dinosaurs were wiped out in a matter of hours in the resulting heat wave [1]. Now where did this asteroid come from, and how did it get here? That's another story entirely for which I don't have a good answer. [0] http://en.wikipedia.org/wiki/Cretaceous%E2%80%93Paleogene_extinction_event http://en.wikipedia.org/wiki/Cretaceous%E2%80%93Paleogene_ex... [1] http://www.radiolab.org/story/dinopocalypse/ http://www.radiolab.org/story/dinopocalypse/
- hasenj 12y ago
  I meant that the gravity from the hypothetical star could have caused a disturbance in one of the asteroid belts and that's why that massive asteroid hit the earth.
  - adventured 12y ago
    Which makes me wonder in line with that thought, whether the alien star in question from this article caused any serious asteroid strikes on earth circa 70,000 years ago.
    - hasenj 12y ago
      The article itself mentions that the start is too small to cause any such thin.
    - jarin 12y ago
      I don't think it's very likely, but it might be possible a comet caused the theorized human population bottleneck around 70,000 years ago? https://en.wikipedia.org/wiki/Toba_catastrophe_theory https://en.wikipedia.org/wiki/Toba_catastrophe_theory
  - mathattack 12y ago
    Yes - good point. Gravity or even collisions if this star had planets around it.
sktrdie 12y ago
Well sure. Isn't everything a series of events leading to something? Even my own existence is a series of events: parents born, meeting at the right moment, having sex at the right time...

by hasenj 12y ago

I'm starting to wonder if a somewhat similar event could have occurred ~66 million years ago and triggered a series of events leading to the extinction of dinosaurs.

Thrymr 12y ago

That is basically the Nemesis hypothesis: http://en.wikipedia.org/wiki/Nemesis_%28hypothetical_star%29 http://en.wikipedia.org/wiki/Nemesis_%28hypothetical_star%29

Sanddancer 12y ago

That's the basis of the Nemesis hypothesis [1]; that supposedly there's a star that roughly orbits the sun and causes havoc every few miillion years. However, it's been pretty much debunked at this point [1]http://en.wikipedia.org/wiki/Nemesis_%28hypothetical_star%29 http://en.wikipedia.org/wiki/Nemesis_%28hypothetical_star%29

hasenj 12y ago
Well it doesn't have to be orbiting the sun and causing this periodically. It could've been a one time event.
tomphoolery 12y ago
Was gonna come in here to ask...will this explain Nemesis as not a recurring event but rather a one-time event caused by that trailing brown dwarf (or the star itself) flinging comets all over the place. It would also explain a lot of other crater-rich surfaces dating back to that time...
- vidarh 12y ago
  Not without time travel... This was only 70 thousand years ago.
- iwwr 12y ago
  If that's true it'd be hard to identify the responsible star since in a few million years it would be thousands of light years away and difficult to measure precise kinematics of it.
- logfromblammo 12y ago
  Given the distances involved, anything that may have had its orbit altered by this event is extremely unlikely to have struck any solid surface in our system already. It may, however, lead to some additional bombardment a few million years from now. By that time, we might have computers of sufficient power working from an astronomical catalog of sufficient completeness to reverse-propagate the catalog far enough to actually blame the passing stars for kicking out comets in our direction.
mangeletti 12y ago
The Nemesis Hypothesis hasn't been debunked.
- dragonwriter 12y ago
  > The Nemesis Hypothesis hasn't been debunked. I rather thought that Nemesis had become a fairly untenable hypothesis in light of the the facts that: (1) Insofar as there is a periodicity to extinctions to explain (what Nemesis was posited to explain), more recent analysis has shown that it is too consistent for any plausible orbit for Nemesis, and (2) A sensitive enough survey to detect stars (including brown dwarfs) within the radius of Earth in which Nemesis would have to exist has been conducted and failed to detect any such star.
  - mangeletti 12y ago
    I'm not sure I understood point #1. Do you mean that the periodicity is too consistent to support the theory of an orbiting body, because an orbiting body would have a less consistent orbit? If so, that's very interesting. Pertaining point #2, I'm not very confident in any empirical data observed at this point in human evolution. It's not to say that scientists aren't working very hard to learn things, but moments like http://www.theguardian.com/science/2015/feb/26/found-a-black-hole-12-billion-times-the-size-of-the-sun http://www.theguardian.com/science/2015/feb/26/found-a-black... tell me that we're going to go through many more "we're absolutely sure / wait, we were wrong" moments, especially when pertaining astronomy and ontology, both fields with many more unknowns than true facts.

mathattack 12y ago

The current consensus is a Manhattan-sized asteroid. [0] The science behind this is pretty strong. What's come open for question is how fast this happened. A new theory posits that the dinosaurs were wiped out in a matter of hours in the resulting heat wave [1]. Now where did this asteroid come from, and how did it get here? That's another story entirely for which I don't have a good answer. [0] http://en.wikipedia.org/wiki/Cretaceous%E2%80%93Paleogene_extinction_event http://en.wikipedia.org/wiki/Cretaceous%E2%80%93Paleogene_ex... [1] http://www.radiolab.org/story/dinopocalypse/ http://www.radiolab.org/story/dinopocalypse/

hasenj 12y ago
I meant that the gravity from the hypothetical star could have caused a disturbance in one of the asteroid belts and that's why that massive asteroid hit the earth.
- adventured 12y ago
  Which makes me wonder in line with that thought, whether the alien star in question from this article caused any serious asteroid strikes on earth circa 70,000 years ago.
  - hasenj 12y ago
    The article itself mentions that the start is too small to cause any such thin.
  - jarin 12y ago
    I don't think it's very likely, but it might be possible a comet caused the theorized human population bottleneck around 70,000 years ago? https://en.wikipedia.org/wiki/Toba_catastrophe_theory https://en.wikipedia.org/wiki/Toba_catastrophe_theory
- mathattack 12y ago
  Yes - good point. Gravity or even collisions if this star had planets around it.

sktrdie 12y ago

Well sure. Isn't everything a series of events leading to something? Even my own existence is a series of events: parents born, meeting at the right moment, having sex at the right time...