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looking to the past
is it theoretically possible to sense from earth the qualities of the light
that was reflected into space in the past from earth could we focus on a certain distance in space say 1000 light years away to build a visual image of the past |
#2
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"Mr Jherek Chamaeleo" wrote in message ... is it theoretically possible to sense from earth the qualities of the light that was reflected into space in the past from earth could we focus on a certain distance in space say 1000 light years away to build a visual image of the past First, we can't even 'see' a planet at stellar distances (for a nearby star, let alone one at 1000 light years away), both in terms of the amount of light reflected from a local star, and in terms of the resolution needed. Then add the fact that you can't 'see' reflected light, until it reflects off something else. Add the albedo of the surface involved, and the fact that the distances involved then double (and the amounts of light then 'quarter' - good old inverse square law), and the answer is 'no'. Not even close... Best Wishes |
#3
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"Mr Jherek Chamaeleo" wrote in message
... is it theoretically possible to sense from earth the qualities of the light that was reflected into space in the past from earth could we focus on a certain distance in space say 1000 light years away to build a visual image of the past You'd need to have something focus the light to form an image on a surface of some sort. Perhaps a gravitational lens could provide the focusing, but what of the projection screen? Light is scattered from nebulae, so that won't do it. And to add to the difficulties, the flux of light from our Earth at the required distance would be so pitifully low as to be entirely swamped by background light. You'd never be able to make out an image. |
#4
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"Mr Jherek Chamaeleo" wrote in message
... is it theoretically possible to sense from earth the qualities of the light that was reflected into space in the past from earth could we focus on a certain distance in space say 1000 light years away to build a visual image of the past Only by imbibing more Rebel Yell than is legal. Clear Skies Chuck Taylor Do you observe the moon? Try the Lunar Observing Group http://groups.yahoo.com/group/lunar-observing/ ************************************************** ********** |
#5
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"Mr Jherek Chamaeleo" wrote in message ... is it theoretically possible to sense from earth the qualities of the light that was reflected into space in the past from earth could we focus on a certain distance in space say 1000 light years away to build a visual image of the past Yeah it is called red shift and CBR |
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