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Mixed Perception...

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Posted by Joanna on January 26, 2004 01:23:25 UTC

I'm not sure if I understand what you're real scenario is...first off...

You're starting with an object leaving at 90% the speed of light, at 1 lightyear from Earth.
Continuously tracking the object with a telescope, it will arrive in however many days it takes.
Your only frame of reference can be you looking through the telescope watching the journey.
I guess I don't understand how this is "appearing" faster than the speed of light?
Since the images you see in the telescope are basically light being relected back, reaching you at the speed of light,
for the object to "appear" faster than the speed of light, means that "light" would have to travel faster than the speed of light.

And I think your scenario is based on you looking at this from 2 different points of reference.
Obviously the object will reach Earth before you see it happen in the telescope.
While you're seeing the object in space, you can look over next to you and see that the object has just reached Earth.
Well, since we know better, we know that the object didn't travel faster than light.
We just have to look back into the telescope to see that.
So it could never "appear" as though it had. Unless you allow yourself see it that way.
You can't use 2 points of reference for this.

I'm really not sure if this is what you were getting at or not. But basically...

Using multiple points of reference only distorts your perception.
Tracking an object with the naked eye, it will appear when it is close enough,
and you will track its journey from that point until it reaches Earth in real-time.
Since we have the aid of high powered telescopes,
this "appearing" as though its faster than light is only an illusion.

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