Would it be possible to.....

[PJay_A]

<p>Ever since I was a kid, I've wondered but never asked and through the years never read anything any where that would neither ask the same or even remotely even hint at an answer. So, here I am writing this, hoping one of you all might know enough to answer the question I've wondered about since my childhood...</p><p>Would it be possible, once space telescope become a great deal more powerful than what they are today, to find reflective (i.e. "natural mirrors") thousands of light years away that's reflecting our own light and would it be possible to capture that reflective light (with extremely powerful future space telescopes) to get a "window of Earth from the past". Future space telescope technology permitting and if these telescopes are ever powerful enough, would Google Earth-style pre-historic surveyance of our planet be possible?</p><p>I don't see it being used following the daily lives of people, but possibly things such as.... Was there a Tower of Bable? Was there a world-wide flood? Did a comet hit our planet 13,000 years ago? Were there lost civilizations such as Atlantis that today&nbsp;are buried under seas or oceans of water or buried deep under volcanic ash?</p>

 

[michaelmozina]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Ever since I was a kid, I've wondered but never asked and through the years never read anything any where that would neither ask the same or even remotely even hint at an answer. So, here I am writing this, hoping one of you all might know enough to answer the question I've wondered about since my childhood...Would it be possible, once space telescope become a great deal more powerful than what they are today, to find reflective (i.e. "natural mirrors") thousands of light years away that's reflecting our own light and would it be possible to capture that reflective light (with extremely powerful future space telescopes) to get a "window of Earth from the past". Future space telescope technology permitting and if these telescopes are ever powerful enough, would Google Earth-style pre-historic surveyance of our planet be possible?I don't see it being used following the daily lives of people, but possibly things such as.... Was there a Tower of Bable? Was there a world-wide flood? Did a comet hit our planet 13,000 years ago? Were there lost civilizations such as Atlantis that today&nbsp;are buried under seas or oceans of water or buried deep under volcanic ash? <br /> Posted by PJay_A</DIV></p><p>Light tends to dissipate and become less intense over time based upon the inverse square law.&nbsp; Even if there was something in deep space that reflected all the arriving photons back at us, by the time it arrived back at Earth, the intensity of the light would dissipated to the point of being useless.&nbsp; I guess the short answer is "no". </p><p>In a "perfect" world, with "perfect" equipment, in "theory" at least, your idea does have merit and it's actually been done (sort of).&nbsp;&nbsp; I remember reading a recent article about astronomers seeing a reflection of a SN1A supernova from plasma cloud.&nbsp; In that case the light source was extremely bright.&nbsp; I'll see if I can find you a link to the supernova article.&nbsp; </p> <div class="Discussion_UserSignature"> It seems to be a natural consequence of our points of view to assume that the whole of space is filled with electrons and flying electric ions of all kinds. - Kristian Birkeland </div>

 

[michaelmozina]

<p>http://blog.wired.com/wiredscience/2008/12/ancient-superno.html</p><p>&nbsp;</p> <div class="Discussion_UserSignature"> It seems to be a natural consequence of our points of view to assume that the whole of space is filled with electrons and flying electric ions of all kinds. - Kristian Birkeland </div>

 

[BoJangles]

<p style="margin-top:0cm;margin-left:0cm;margin-right:0cm" class="MsoNormal"><font face="Calibri" size="3">It&rsquo;s an interesting thought, but unfortunately no. Ignoring all the fundamental physics problems you would encounter and the fact the earth&rsquo;s light would be overpowered by that of the sun; here are some logical issues with your proposal. </font></p><p style="margin-top:0cm;margin-left:0cm;margin-right:0cm" class="MsoNormal"><font face="Calibri" size="3">For every amount of time you wanted to look back, you would have to find a reflective surface at precisely the right distance away, additionally, even if any such reflective phenomenon did exist <span>&nbsp;</span>(at a fixed distance) , they would need to be accompanied by some really big lenses(positioned perfectly). Inverse squares 0wnz j00</font></p><font face="Calibri" size="3">&nbsp;</font> <p style="margin-top:0cm;margin-left:0cm;margin-right:0cm" class="MsoNormal"><font size="3"><font face="Calibri">Though why put a good thought to waste you could always add some more and&nbsp;write some sci-fi <span>&nbsp;</span></font><span style="font-family:Wingdings"><span>J</span></span><font face="Calibri"> </font></font></p><p>---</p><p>Oops beaten to it..</p><p>What michaelmozina said ^</p> <div class="Discussion_UserSignature"> <p align="center"><font color="#808080">-------------- </font></p><p align="center"><font size="1" color="#808080"><em>Let me start out with the standard disclaimer ... I am an idiot, I know almost nothing, I haven’t taken calculus, I don’t work for NASA, and I am one-quarter Bulgarian sheep dog.  With that out of the way, I have several stupid questions... </em></font></p><p align="center"><font size="1" color="#808080"><em>*** A few months blogging can save a few hours in research ***</em></font></p> </div>

 

[cosmictraveler]

<p><font size="5">Earth doesn't make its own light, it is only reflecting the light from the sun which would make it very, very dim a few lightyears away so dim in fact it wouldn't even be seen. </font></p><p>&nbsp;</p><p>&nbsp;</p> <div class="Discussion_UserSignature"> <p>It does not require many words to speak the truth. Chief Joseph</p> </div>

 

[DrRocket]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Ever since I was a kid, I've wondered but never asked and through the years never read anything any where that would neither ask the same or even remotely even hint at an answer. So, here I am writing this, hoping one of you all might know enough to answer the question I've wondered about since my childhood...Would it be possible, once space telescope become a great deal more powerful than what they are today, to find reflective (i.e. "natural mirrors") thousands of light years away that's reflecting our own light and would it be possible to capture that reflective light (with extremely powerful future space telescopes) to get a "window of Earth from the past". Future space telescope technology permitting and if these telescopes are ever powerful enough, would Google Earth-style pre-historic surveyance of our planet be possible?I don't see it being used following the daily lives of people, but possibly things such as.... Was there a Tower of Bable? Was there a world-wide flood? Did a comet hit our planet 13,000 years ago? Were there lost civilizations such as Atlantis that today&nbsp;are buried under seas or oceans of water or buried deep under volcanic ash? <br />Posted by PJay_A</DIV></p><p>To do what you propose you would need a surface that produces specular reflections (like a mirror as opposed to just a white reflective surface) located at a precise distance depending the the time frame for whatever it is that you wish to observe, precisely oriented to reflect the light from the Earth in its position a the time to be observed to Earth in its position now, and a telescope with sufficient resolving power (not magnifying power, but resolving power) to be able to see the events unfold.</p><p>Let's consider your hypothetical event from 13,000 years ago. You would need to be able to resolve at a distance of 13,000 light years (that is now far the light would have traveled in the trip to the mirror and back) objects that would be difficult to resolve&nbsp;with the Hubble telescope at a distance of a couple of hundred miles.&nbsp; Pile on top of that the loss of brightness with distance and the effect of anything less than a perfect reflecting surface, the lack of any reflecting surface, perfect or not, at the required distance, and you can quickly conclude that such an observation would be impossible as a practical matter. <br /></p> <div class="Discussion_UserSignature"> </div>

 

[derekmcd]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Ever since I was a kid, I've wondered but never asked and through the years never read anything any where that would neither ask the same or even remotely even hint at an answer. So, here I am writing this, hoping one of you all might know enough to answer the question I've wondered about since my childhood...Would it be possible, once space telescope become a great deal more powerful than what they are today, to find reflective (i.e. "natural mirrors") thousands of light years away that's reflecting our own light and would it be possible to capture that reflective light (with extremely powerful future space telescopes) to get a "window of Earth from the past". Future space telescope technology permitting and if these telescopes are ever powerful enough, would Google Earth-style pre-historic surveyance of our planet be possible?I don't see it being used following the daily lives of people, but possibly things such as.... Was there a Tower of Bable? Was there a world-wide flood? Did a comet hit our planet 13,000 years ago? Were there lost civilizations such as Atlantis that today&nbsp;are buried under seas or oceans of water or buried deep under volcanic ash? <br /> Posted by PJay_A</DIV></p><p>You might have better luck using a medium to capture and slow light down and, in a sense, store it. </p> <div class="Discussion_UserSignature"> <div> </div><br /><div><span style="color:#0000ff" class="Apple-style-span">"If something's hard to do, then it's not worth doing." - Homer Simpson</span></div> </div>

 

[derekmcd]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Earth doesn't make its own light, it is only reflecting the light from the sun which would make it very, very dim a few lightyears away so dim in fact it wouldn't even be seen. &nbsp;&nbsp; <br /> Posted by cosmictraveler</DIV></p><p>You're point is valid, but I'd like to point out that the Earth does generate is own internal heat that escapes into space.&nbsp; Given a powerful enough scope, Earth's own infrared radiation could be seen at quite some distance.&nbsp; Infrared radiation is light... just not visible to the human eye.</p> <div class="Discussion_UserSignature"> <div> </div><br /><div><span style="color:#0000ff" class="Apple-style-span">"If something's hard to do, then it's not worth doing." - Homer Simpson</span></div> </div>

 

[vogon13]

<p>&nbsp;</p><p>This doesn't make the task any easier, but even Stephen Hawking is convinced (and I somewhat agree) the information in the photons reflected from earth cannot be destroyed.</p><p>&nbsp;</p><p>&nbsp;</p> <div class="Discussion_UserSignature"> <p><font color="#ff0000"><strong>TPTB went to Dallas and all I got was Plucked !!</strong></font></p><p><font color="#339966"><strong>So many people, so few recipes !!</strong></font></p><p><font color="#0000ff"><strong>Let's clean up this stinkhole !!</strong></font> </p> </div>

 

[centsworth_II]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'> ...Stephen Hawking is convinced (and I somewhat agree) the information in the photons reflected from earth cannot be destroyed.&nbsp;&nbsp; <br /> Posted by vogon13</DIV></p><p>What about when the photon is absorbed? </p><p><font color="#800000">"Photons are absorbed in a solid through a process known as the photoelectric effect<strong> </strong>whereby a photon interacts with an electron by giving all its energy to the electron. In effect, the photon disappears and energy is transferred to an electron."</font> http://acept.asu.edu/PiN/rdg/visnxray/visnxray.shtml</p> <div class="Discussion_UserSignature"> </div>

 

[DrRocket]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>&nbsp;This doesn't make the task any easier, but even Stephen Hawking is convinced (and I somewhat agree) the information in the photons reflected from earth cannot be destroyed.&nbsp;&nbsp; <br />Posted by vogon13</DIV></p><p>Sure, all you need to do is recover all of the pristine photons and all of the particles with which the other photons interacted, and emissions from those interactions and ther interactions, ......&nbsp; Then reconstruct the original quantum state.&nbsp; That might prove to be a formidable undertaking. </p> <div class="Discussion_UserSignature"> </div>

 

[Bflowing]

<p>Its a wonderful idea, especially for a sci fi story.&nbsp; The photons from the asteroid that wiped out the dinosaurs are still out there.&nbsp; Imagine a lens placed well into space, and connected to the most powerful computer imaginable.&nbsp; One that can discriminate among all of the billions of photons per second received and produce a usable image.</p><p>Wow, I see a series of great stories!</p> <div class="Discussion_UserSignature"> </div>

 

[DrRocket]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Its a wonderful idea, especially for a sci fi story.&nbsp; The photons from the asteroid that wiped out the dinosaurs are still out there.&nbsp; Imagine a lens placed well into space, and connected to the most powerful computer imaginable.&nbsp; One that can discriminate among all of the billions of photons per second received and produce a usable image.Wow, I see a series of great stories! <br />Posted by Bflowing</DIV></p><p>How did you conclude that the photons are out there ?&nbsp; They are unless they happened to hit an atom somewhere, and there are a lot of atoms out there.</p><p>Also, the ones that are out there have traveling away from us at the speed of light for about 65 million years, and that means they are pretty far away now, say 25 times as far as the Andromeda galaxy.&nbsp; How do you intend to catch them ?&nbsp; How do you intend to, at a very great distance, discriminate between photons from the Earth and photons from somewhere nearby, like the sun ?&nbsp;All photons of a given wavelength are identical, not just kind of similar, but absolutely identical.&nbsp; You are talking distances at which&nbsp;we can't&nbsp;generally resolve individual stars, even with the Hubble telescope, and you are talking about trying to resolve&nbsp;features of a meter or so in length with luminosity rather puny when compared to a star. &nbsp; </p> <div class="Discussion_UserSignature"> </div>

 

[centsworth_II]

What we really need to do is find an intergalactic civilization that visited Jurassic-age&nbsp; Earth and made a visual record which is now buried somewhere in their science archives. <div class="Discussion_UserSignature"> </div>

 

[Bflowing]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>How did you conclude that the photons are out there ?&nbsp; They are unless they happened to hit an atom somewhere, and there are a lot of atoms out there.Also, the ones that are out there have traveling away from us at the speed of light for about 65 million years, and that means they are pretty far away now, say 25 times as far as the Andromeda galaxy.&nbsp; How do you intend to catch them ?&nbsp; How do you intend to, at a very great distance, discriminate between photons from the Earth and photons from somewhere nearby, like the sun ?&nbsp;All photons of a given wavelength are identical, not just kind of similar, but absolutely identical.&nbsp; You are talking distances at which&nbsp;we can't&nbsp;generally resolve individual stars, even with the Hubble telescope, and you are talking about trying to resolve&nbsp;features of a meter or so in length with luminosity rather puny when compared to a star. &nbsp; <br />Posted by DrRocket</DIV><br /><br />Lol, remember I said a sci-fi story!&nbsp; There only has to be a slight plausibility!</p><p>It doesn't matter if they hit other atoms, as long as the atom produces a duplicate photon.&nbsp; And one photon will not give a usefull image, we need several to produce an image.&nbsp; So we need a really, really big and powerful computer, or several scattered over a couple of AU in a phased array.&nbsp; Hey, I'm beginning to see a TV series here...</p> <div class="Discussion_UserSignature"> </div>

 

[michaelmozina]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>You're point is valid, but I'd like to point out that the Earth does generate is own internal heat that escapes into space.&nbsp; Given a powerful enough scope, Earth's own infrared radiation could be seen at quite some distance.&nbsp; Infrared radiation is light... just not visible to the human eye. <br /> Posted by derekmcd</DIV></p><p>Not to mention all the human activity and lights from cities, etc.&nbsp; I guess even our ancestors had fire and campfires. </p> <div class="Discussion_UserSignature"> It seems to be a natural consequence of our points of view to assume that the whole of space is filled with electrons and flying electric ions of all kinds. - Kristian Birkeland </div>

 

[michaelmozina]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Its a wonderful idea, especially for a sci fi story.&nbsp; The photons from the asteroid that wiped out the dinosaurs are still out there.&nbsp; Imagine a lens placed well into space, and connected to the most powerful computer imaginable.&nbsp; One that can discriminate among all of the billions of photons per second received and produce a usable image.Wow, I see a series of great stories! <br /> Posted by Bflowing</DIV></p><p>I can even think of ways of giving it an air of plausibility by using some ficticious sophisticated looking equipment that is designed to separate photons by their redshift pattern so that only the correct photons are used to create the image of Earth.&nbsp; It would make for a good sci-fi episode with a little creativity. </p> <div class="Discussion_UserSignature"> It seems to be a natural consequence of our points of view to assume that the whole of space is filled with electrons and flying electric ions of all kinds. - Kristian Birkeland </div>

 

[michaelmozina]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>What we really need to do is find an intergalactic civilization that visited Jurassic-age&nbsp; Earth and made a visual record which is now buried somewhere in their science archives. <br /> Posted by centsworth_II</DIV></p><p>That would also be a great story line. </p> <div class="Discussion_UserSignature"> It seems to be a natural consequence of our points of view to assume that the whole of space is filled with electrons and flying electric ions of all kinds. - Kristian Birkeland </div>

 

[DrRocket]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>What we really need to do is find an intergalactic civilization that visited Jurassic-age&nbsp; Earth and made a visual record which is now buried somewhere in their science archives. <br />Posted by centsworth_II</DIV></p><p><br /><img src="http://sitelife.space.com/ver1.0/Content/images/store/9/8/398453ec-ba35-4eb3-a830-8d25ca921342.Medium.jpg" alt="" /><br /><br /></p> <div class="Discussion_UserSignature"> </div>