How Do Scientists Know Light from Distant Heavenly Bodies Isn't a Reflection?

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Scientists determine that light from distant heavenly bodies is not merely a reflection through observations of redshift and the behavior of light in spacetime. The light emitted from these objects travels directly to Earth, rather than being reflected off other surfaces, which is supported by the principles of physics and cosmology. When observing a red object, the lack of visible red light in the surroundings can be attributed to factors such as the object's light not being intense enough or being absorbed by other materials. Additionally, light must travel directly to the observer to be perceived, as photons traveling perpendicular to the observer's line of sight remain unseen. Understanding these concepts is essential for interpreting astronomical observations accurately.
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1. How does scientists know that the light from far distant heavenly bodies are actually from those, or some kind of reflection?

2. If a red object reflects only red frequency light, why I do not see red light from that object to the surrounding?
 
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1. Some cosmologists speculate that far-field galactic images are reflected by spacetime curvature to produce most of the "galaxies" apparent there.

2. If I understand you correctly, perhaps the light it reflects is not intense enough, that it is en route to you, or that it shines upon objects that absorb, rather than reflect, red light. Otherwise, it might not have a train of photons that eventually leads back to you, the observer. You cannot observe a photon traveling perpendicular to you, i. e., that does not at sometime strike your senses directly.

What made you think of this situation? The cosmological redshift?
 
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