Why won't an object be seen as it is today, if you could go to its location instantly?
A: Astronomical objects change very rapidly so even though only a short time has passed as its light travels through space, it will be in a completely different state now.
B: Light has been traveling a large distance through space since it left the object; we see the object as it will be in the future.
C: Light has been traveling a large distance through space since it left the object; we see the object as it was in the past.
D: Photons decay as they pass through space so information is lost about what they looked like when the light was emitted.
E: All the objects will have exploded by now.
Answer: C: Light has been traveling a large distance through space since it left the object; we see the object as it was in the past.
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