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I know its just a coincidence that the meteor hit during a lunar eclipse while millions of people might have been watching (and probably not seeing it). But, it

I know its just a coincidence that the meteor hit during a lunar eclipse while millions of people might have been watching (and probably not seeing it). But, it gives me chills to think that lump of rock has been orbiting through the solar system for possibly billions of years with its unknown fate already sealed. All it took was for the Sun and all the planets and moons to go through their cycles an uncountable number of times to bring it to its ultimate conclusion. Now, unknown asteroid, your watch is done.

anonytrary 8y ago
If you think about it, the Earth and Moon and every other lump of rock in the universe are not fundamentally different than this one. Eventually their watches will end, too.
- balabaster 8y ago
  Yeah, it's weird like the light from some of the stars takes so long to get to us that when it left home, the dinosaurs were still roaming the earth... and then after some 65 million years, it hits us allowing us to see that star which was once there in its place in the sky, and one assumes still is, but we can't be sure, and that's that. Done. Over. Gone. Though, I supposed given that energy can neither be created nor destroyed it somehow changes form and is absorbed in some fashion. Crazy for something to spend so long travelling in a straight(ish) line and the BAM! Finished.
  - quakeguy 8y ago
    Some light that reaches us was sent out when earth wasn't even formed... And some light will never reach us, the universe is expanding at a higher rate, future astronomers will find the sky empty. That's crazy as well.
  - gowld 8y ago
    Light travels in perfectly straight lines (geodesics in spacetime). The trip takes 0 time and 0 distance for the photon, from emission til absorption.
    - balabaster 8y ago
      Light's path is affected by gravity of the bodies it passes in space, so technically it doesn't travel in perfectly straight lines at all.
      - saagarjha 8y ago
        The parent commenter mentions this when discussing "geodesics in spacetime".
    - peanutz454 8y ago
      0 time due to time dilation, but 0 distance?
      - 12298765 8y ago
        Yeah, due to length contraction
      - jstanley 8y ago
        I think the reason it experiences 0 time is actually because of length contraction. The photon experiences the entire universe contracted to 0 length, so of course it travels along its path in 0 time.
        Retra 8y ago
        "For the photon" and "the photon's experience" are nonsense concepts. There is no such frame of reference, so it makes no sense to postulate what things would look like from it.
        warent 8y ago
        Unless you have a better theory of spacetime and gravity than Einstein, it's safe to say frames of reference are a fundamental aspect of the nature of the universe. https://en.m.wikipedia.org/wiki/Observer_(special_relativity) https://en.m.wikipedia.org/wiki/Observer_(special_relativity...
  - warent 8y ago
    Light that traveled across trillions of trillions of kilometers, passing endless galaxies, nebulae, planets, (possibly extraterrestrial lifeforms) and other breathtaking interstellar objects, all so that it can end its journey on the bum of a random tourist at on a beach. What a world!
    - JCharante 8y ago
      Fortunately for the light, its trip was pretty instantaneous.
      - mark-r 8y ago
        Relatively speaking.
      - balabaster 8y ago
        It's a hard concept to wrap your head around. Eons of time have passed for us, planets have formed, entire species have evolved, flourished and become extinct, ice ages have happened, wars, humanity has grown up and has reached a point where we're on the cusp of escaping the boundaries of this rock we call home... but for the light, it blinked into existence and out again, in a moment, time and distance completely irrelevant to its existence... it's as if instead of traveling across our space and time, it is merely passing through from some other dimension.
  - sethammons 8y ago
    The one that gets me: in the future, the expanded universe will be so spread out that there will be no detectable anything outside of your immediate solar neighborhood. No stars. No nothing. There will be no reason to assume the rest of the universe even exists. We live at an amazing time in our universe's history where we can see stars and learn from them.
    - dredmorbius 8y ago
      The expansion constant is weaker than gravity, such that gravitationally-bound structures, including everything from asteroids up through galactic clusters, will survive. Beyond the local galactic cluster though -- quite possibly nothing.
      - ValleyOfTheMtns 8y ago
        > Beyond the local galactic cluster though -- quite possibly nothing. Do you mean the Local Group? https://en.wikipedia.org/wiki/Local_Group https://en.wikipedia.org/wiki/Local_Group Or the Local Supercluster? https://en.wikipedia.org/wiki/Virgo_Supercluster https://en.wikipedia.org/wiki/Virgo_Supercluster
        dwaltrip 8y ago
        The Local Group is gravitationally bound, but that isn't the case with the local supercluster. I believe that most (all?) superclusters are not gravitationally bound. In fact, the entire local group will eventually be a single galaxy I believe, mostly composed of the contents of the Milky Way and Andromeda galaxies.
  - harshulpandav 8y ago
    Seeing dinosaurs could be possible if a 4 light year wide telescope is sent via a worm hole to one of the galaxies in the Virgo cluster (65m light years away) and live imagery of Earth (not via worm hole) is sent back via the worm hole to Earth.
    - balabaster 8y ago
      I think this would give us all kinds of insight we're totally wrong about at the moment.
  - swebs 8y ago
    Energy is created all the time in the form of Dark Energy.
SiempreViernes 8y ago
Well, it is not that much coincidence that it was seen during an event where millions paid extra close attention and the moon itself was less bright.
cwkoss 8y ago
ASTEROID is evolving... ... ... BOOM! ASTEROID is now CRATER. triumphant music
jessriedel 8y ago
> for possibly billions of years with its unknown fate already sealed Probably not for quite that long. The path of a meteor is only going to be deterministic on a timescale given roughly by the largest Lyapunov exponent associated with its orbit. On longer timescales, even the very tiny irreducible quantum uncertainty in its initial state would be enough to cause it to miss the Moon. Not sure what the Lyapunov time is for these meteors, but typical time scales for planets are 2M-200M years. For small things like meteors, there are likely other sources of noise (e.g., solar wind pressure) with quantum uncertainty that lead to non-determinism even faster.
- gerdesj 8y ago
  >> for possibly billions of years with its unknown fate already sealed >Probably not for quite that long. No, you are right "Probably not for quite that long" - way longer. Parent was looking deep in wonder at something and frankly the bits that make up the meteor are as old as they are old. Those atoms have been hanging around the place for quite a while but I'm not too sure that anyone can really decide when they should be considered as "existing" as a meteor.
  - azernik 8y ago
    GP was talking about determinism (chaos theory), not the Ship of Theseus problem. i.e. the same meteor has existed for a long time, but orbital dynamics in the real solar system aren't really deterministic on such long time scales.
- bellerose 8y ago
  Quantum uncertainty doesn’t change the outcome from being deterministic.
- nonbel 8y ago
  >"The path of a meteor is only going to be deterministic on a timescale given roughly by the largest Lyapunov exponent associated with its orbit. On longer timescales, even the very tiny irreducible quantum uncertainty in its initial state would be enough to cause it to miss the Moon." My understanding is that chaotic systems are still deterministic, the state at some later time is just very sensitive to the initial conditions (which it may be impossible to know with much precision). "Irreducible quantum uncertainty" is something else that has nothing to do with Lyapunov time. I also see Lyapunov died in 1918,[1] while the uncertainty principle was introduced in 1927.[2] [1] https://en.wikipedia.org/wiki/Aleksandr_Lyapunov https://en.wikipedia.org/wiki/Aleksandr_Lyapunov [2] https://en.wikipedia.org/wiki/Uncertainty_principle https://en.wikipedia.org/wiki/Uncertainty_principle
miyhhbftdx 8y ago
Dr. Brian Greene steadfastly believes that all future events are already scripted. There is no free will. ^_^
noonespecial 8y ago
Something the size of a football hit the moon so hard we saw it happen 238,900 miles away... That's a spectacular end if you ask me.
samstave 8y ago
Why dO we not have a continuous high def stream of the moon period One should be able to go to moon.com and literally see the state of the moon at that exact moment i. Real time, i. High def
- justinator 8y ago
  I think we do it's just called, "the sky"
  - samstave 8y ago
    If I run really fast, I can keep the moon in my vision continuously... Why are your legs so weak?
    - SmellyGeekBoy 8y ago
      What are you planning exactly, just checking up on the moon during the day? Get back to work! ;)
    - justinator 8y ago
      Why are your legs so weak? I get that this is a joke, but it's funny you're asking someone like me about being out of shape/weak. I'm laughing, just in a different way than you may have expected.
- dotancohen 8y ago
  Who is "we"? If you mean your local space agency, then ask whoever is funding them why they don't fund a continuous moon stream.
lholden 8y ago
Meteor impacts happen way more frequently than you might realize... and they hit Earth all the time too. :) Heck, last year we had a notable meteor come down where I live in Michigan. Obviously though... having significantly more people watching the moon at the time lends itself to this kind of thing being a lot more likely to be noticed.
IAmGraydon 8y ago
Well, technically every atom in your body has been waiting around for billions of years to become an animated meatbag. Everything has an impressive history if you think about it.

anonytrary 8y ago

If you think about it, the Earth and Moon and every other lump of rock in the universe are not fundamentally different than this one. Eventually their watches will end, too.

balabaster 8y ago
Yeah, it's weird like the light from some of the stars takes so long to get to us that when it left home, the dinosaurs were still roaming the earth... and then after some 65 million years, it hits us allowing us to see that star which was once there in its place in the sky, and one assumes still is, but we can't be sure, and that's that. Done. Over. Gone. Though, I supposed given that energy can neither be created nor destroyed it somehow changes form and is absorbed in some fashion. Crazy for something to spend so long travelling in a straight(ish) line and the BAM! Finished.
- quakeguy 8y ago
  Some light that reaches us was sent out when earth wasn't even formed... And some light will never reach us, the universe is expanding at a higher rate, future astronomers will find the sky empty. That's crazy as well.
- gowld 8y ago
  Light travels in perfectly straight lines (geodesics in spacetime). The trip takes 0 time and 0 distance for the photon, from emission til absorption.
  - balabaster 8y ago
    Light's path is affected by gravity of the bodies it passes in space, so technically it doesn't travel in perfectly straight lines at all.
    - saagarjha 8y ago
      The parent commenter mentions this when discussing "geodesics in spacetime".
  - peanutz454 8y ago
    0 time due to time dilation, but 0 distance?
    - 12298765 8y ago
      Yeah, due to length contraction
    - jstanley 8y ago
      I think the reason it experiences 0 time is actually because of length contraction. The photon experiences the entire universe contracted to 0 length, so of course it travels along its path in 0 time.
      - Retra 8y ago
        "For the photon" and "the photon's experience" are nonsense concepts. There is no such frame of reference, so it makes no sense to postulate what things would look like from it.
        warent 8y ago
        Unless you have a better theory of spacetime and gravity than Einstein, it's safe to say frames of reference are a fundamental aspect of the nature of the universe. https://en.m.wikipedia.org/wiki/Observer_(special_relativity) https://en.m.wikipedia.org/wiki/Observer_(special_relativity...
- warent 8y ago
  Light that traveled across trillions of trillions of kilometers, passing endless galaxies, nebulae, planets, (possibly extraterrestrial lifeforms) and other breathtaking interstellar objects, all so that it can end its journey on the bum of a random tourist at on a beach. What a world!
  - JCharante 8y ago
    Fortunately for the light, its trip was pretty instantaneous.
    - mark-r 8y ago
      Relatively speaking.
    - balabaster 8y ago
      It's a hard concept to wrap your head around. Eons of time have passed for us, planets have formed, entire species have evolved, flourished and become extinct, ice ages have happened, wars, humanity has grown up and has reached a point where we're on the cusp of escaping the boundaries of this rock we call home... but for the light, it blinked into existence and out again, in a moment, time and distance completely irrelevant to its existence... it's as if instead of traveling across our space and time, it is merely passing through from some other dimension.
- sethammons 8y ago
  The one that gets me: in the future, the expanded universe will be so spread out that there will be no detectable anything outside of your immediate solar neighborhood. No stars. No nothing. There will be no reason to assume the rest of the universe even exists. We live at an amazing time in our universe's history where we can see stars and learn from them.
  - dredmorbius 8y ago
    The expansion constant is weaker than gravity, such that gravitationally-bound structures, including everything from asteroids up through galactic clusters, will survive. Beyond the local galactic cluster though -- quite possibly nothing.
    - ValleyOfTheMtns 8y ago
      > Beyond the local galactic cluster though -- quite possibly nothing. Do you mean the Local Group? https://en.wikipedia.org/wiki/Local_Group https://en.wikipedia.org/wiki/Local_Group Or the Local Supercluster? https://en.wikipedia.org/wiki/Virgo_Supercluster https://en.wikipedia.org/wiki/Virgo_Supercluster
      - dwaltrip 8y ago
        The Local Group is gravitationally bound, but that isn't the case with the local supercluster. I believe that most (all?) superclusters are not gravitationally bound. In fact, the entire local group will eventually be a single galaxy I believe, mostly composed of the contents of the Milky Way and Andromeda galaxies.
- harshulpandav 8y ago
  Seeing dinosaurs could be possible if a 4 light year wide telescope is sent via a worm hole to one of the galaxies in the Virgo cluster (65m light years away) and live imagery of Earth (not via worm hole) is sent back via the worm hole to Earth.
  - balabaster 8y ago
    I think this would give us all kinds of insight we're totally wrong about at the moment.
- swebs 8y ago
  Energy is created all the time in the form of Dark Energy.

SiempreViernes 8y ago

Well, it is not that much coincidence that it was seen during an event where millions paid extra close attention and the moon itself was less bright.

cwkoss 8y ago

ASTEROID is evolving... ... ... BOOM! ASTEROID is now CRATER. triumphant music

jessriedel 8y ago

> for possibly billions of years with its unknown fate already sealed Probably not for quite that long. The path of a meteor is only going to be deterministic on a timescale given roughly by the largest Lyapunov exponent associated with its orbit. On longer timescales, even the very tiny irreducible quantum uncertainty in its initial state would be enough to cause it to miss the Moon. Not sure what the Lyapunov time is for these meteors, but typical time scales for planets are 2M-200M years. For small things like meteors, there are likely other sources of noise (e.g., solar wind pressure) with quantum uncertainty that lead to non-determinism even faster.

gerdesj 8y ago
>> for possibly billions of years with its unknown fate already sealed >Probably not for quite that long. No, you are right "Probably not for quite that long" - way longer. Parent was looking deep in wonder at something and frankly the bits that make up the meteor are as old as they are old. Those atoms have been hanging around the place for quite a while but I'm not too sure that anyone can really decide when they should be considered as "existing" as a meteor.
- azernik 8y ago
  GP was talking about determinism (chaos theory), not the Ship of Theseus problem. i.e. the same meteor has existed for a long time, but orbital dynamics in the real solar system aren't really deterministic on such long time scales.
bellerose 8y ago
Quantum uncertainty doesn’t change the outcome from being deterministic.
nonbel 8y ago
>"The path of a meteor is only going to be deterministic on a timescale given roughly by the largest Lyapunov exponent associated with its orbit. On longer timescales, even the very tiny irreducible quantum uncertainty in its initial state would be enough to cause it to miss the Moon." My understanding is that chaotic systems are still deterministic, the state at some later time is just very sensitive to the initial conditions (which it may be impossible to know with much precision). "Irreducible quantum uncertainty" is something else that has nothing to do with Lyapunov time. I also see Lyapunov died in 1918,[1] while the uncertainty principle was introduced in 1927.[2] [1] https://en.wikipedia.org/wiki/Aleksandr_Lyapunov https://en.wikipedia.org/wiki/Aleksandr_Lyapunov [2] https://en.wikipedia.org/wiki/Uncertainty_principle https://en.wikipedia.org/wiki/Uncertainty_principle

miyhhbftdx 8y ago

Dr. Brian Greene steadfastly believes that all future events are already scripted. There is no free will. ^_^

noonespecial 8y ago

Something the size of a football hit the moon so hard we saw it happen 238,900 miles away... That's a spectacular end if you ask me.

samstave 8y ago

Why dO we not have a continuous high def stream of the moon period One should be able to go to moon.com and literally see the state of the moon at that exact moment i. Real time, i. High def

justinator 8y ago
I think we do it's just called, "the sky"
- samstave 8y ago
  If I run really fast, I can keep the moon in my vision continuously... Why are your legs so weak?
  - SmellyGeekBoy 8y ago
    What are you planning exactly, just checking up on the moon during the day? Get back to work! ;)
  - justinator 8y ago
    Why are your legs so weak? I get that this is a joke, but it's funny you're asking someone like me about being out of shape/weak. I'm laughing, just in a different way than you may have expected.
dotancohen 8y ago
Who is "we"? If you mean your local space agency, then ask whoever is funding them why they don't fund a continuous moon stream.

lholden 8y ago

Meteor impacts happen way more frequently than you might realize... and they hit Earth all the time too. :) Heck, last year we had a notable meteor come down where I live in Michigan. Obviously though... having significantly more people watching the moon at the time lends itself to this kind of thing being a lot more likely to be noticed.

IAmGraydon 8y ago

Well, technically every atom in your body has been waiting around for billions of years to become an animated meatbag. Everything has an impressive history if you think about it.