Why Aren't Laser Beams Bent More When Measuring the Moon's Distance?

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The discussion centers on the bending of laser beams used to measure the Moon's distance and the implications of mass on gravitational effects. It highlights a misconception regarding gravitational acceleration and mass, clarifying that even massless objects experience curved trajectories in a gravitational field. The conversation notes that while laser beams are indeed bent by gravity, the degree of bending is minimal. This subtle bending is consistent with the principles of general relativity, which predicts light's trajectory is affected by gravity. Understanding these nuances is crucial for accurate lunar distance measurements.
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Not that this article here can compete with mathematical descriptions or "real" physics but it is well written and fast to read and may provide some answers to the repeating questions about the different consequences of mass.
 
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fresh_42 said:
Not that this article here can compete with mathematical descriptions or "real" physics but it is well written and fast to read and may provide some answers to the repeating questions about the different consequences of mass.
I have read only till it says:
"If Earth had no mass, it wouldn’t feel the curvature of the well and would fly away in a straight line. That’s general relativity in a funnel shaped nut-shell."
This is incorrect: Galilei showed that gravitational acceleration doesn't depend on mass, so even a massless object's trajectory is curved in a gravitational field. The general relativity result is similar, in fact light trajectory is curved in this theory too, just twice as what results from Newtonian mechanics.

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lightarrow
 
lightarrow said:
I have read only till it says:
"If Earth had no mass, it wouldn’t feel the curvature of the well and would fly away in a straight line. That’s general relativity in a funnel shaped nut-shell."
This is incorrect: Galilei showed that gravitational acceleration doesn't depend on mass, so even a massless object's trajectory is curved in a gravitational field. The general relativity result is similar, in fact light trajectory is curved in this theory too, just twice as what results from Newtonian mechanics.

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lightarrow
Sounds correct. But then why aren't the laser beams bent we send to the moon to measure it's distance?
 
fresh_42 said:
Sounds correct. But then why aren't the laser beams bent we send to the moon to measure it's distance?
They are bent, but by a very tiny amount.
 
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