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Author Topic: Optical Illusion ?  (Read 1209 times)

Offline Quark

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Optical Illusion ?
« on: 15/09/2012 12:37:39 »
What really is it about the Hubble telescope that brings light to it's lens faster than the speed of light itself ?


 

Offline JP

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Re: Optical Illusion ?
« Reply #1 on: 15/09/2012 14:03:41 »
Hi Quark,

Could you elaborate a bit?  Light everywhere is limited by the speed of light, including in the Hubble.
 

Offline Quark

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Re: Optical Illusion ?
« Reply #2 on: 15/09/2012 14:31:31 »
If a telescope can enable us to instantly see the light from galaxies 11 billion light years away then what is the actual scientific explanation for this ?
 

Offline JP

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Re: Optical Illusion ?
« Reply #3 on: 15/09/2012 14:35:11 »
Ah.  Good question. 

It actually takes the light 11 billion years to reach us, so we're seeing light that left the galaxy 11 billion years ago, which has been traveling at the speed of light to reach us.
 

Offline Quark

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Re: Optical Illusion ?
« Reply #4 on: 15/09/2012 15:46:59 »
Excellent answer JP, now for the million dollar question, if that light that we can see 11 billion light years away originated from a person holding a very powerful flashlight, then would we also be able to see the person even though he died billions of years ago ?
 

Offline JP

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Re: Optical Illusion ?
« Reply #5 on: 15/09/2012 16:11:48 »
Yep.  In fact, this happens a lot with stars we observe.  Many of them have gone supernova, but we haven't seen it yet because the light from the supernova hasn't gotten here yet.  We see the star as it was millions or billions of years go
 

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Re: Optical Illusion ?
« Reply #5 on: 15/09/2012 16:11:48 »

 

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