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space mirror

A mirror in space to see into the past
  (+4, -1)
(+4, -1)
  [vote for,

Light takes time to reach us, and the further it has to travel, the longer it takes. So when we look in a mirror, we're actually seeing what we looked like a fraction of a second ago. Imagine, then, if we could put a gigantic mirror in space. When we looked at that mirror with a telescope, we would see things that happened on Earth in the past -- and the further away the mirror was, the further into the past we could see. Obviously there are limits to what could be seen -- you'd only be able to get a good view of events that took place outdoors, under clear skies, and in the daytime -- but it would still enable us to revisit many classic sporting contests, military conflicts, and so forth. If the mirror was far enough away, we could use it to watch people and events that were never captured on film. How about it, NASA?
Peller, Aug 23 2001


       so we would finally find out who _really_shot jfk?   

       nice idea, but i think that it would only work for relatively recent events. for example, if you wanted to see something that occurred one year ago, the mirror would have to be postioned one light year away, but then it would take another year to see the reflection. so you would have to wait twice as long as the amount of time that you wanted to go back and see. or something like that.
mihali, Aug 23 2001

       Baked in the oven of sci-fi. It's called retrograde chronoscopy.
The Military, Aug 23 2001

       you can only see things that hapen after you launch the mirror unless you can move it into place at faster than light speed... ie you can't... it could be good for solving crimes thoug if it were far enough away 12 light hours? and you had a good enough telescope you could see exactly what happened somewhere 24 hours ago...
RobertKidney, Aug 23 2001

       Baked in households daily. It's called denial.
thumbwax, Aug 23 2001

       Cute idea, but it does have the limitation that it can only be used to see events that occurred after the launch of the mirror - finding out who shot JFK would (as I understand it) be beyond the scope of this device. That is, of course assuming that we had not already launched a space mirror well before his assassination.   

       [Ooh, I hate it when someone gets an annotation up while I'm still writing mine. Particularly when they say the same thing and especially when I'm having that [PeterSealy] moment. Ooh I could just... Ooh... [annotation-mfd] ]
st3f, Aug 23 2001

       The video tape lobby would never allow it.
pathetic, Aug 24 2001


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