Planets - Effective Temperature vs Actual Temperature

AI Thread Summary
The discussion centers on the discrepancy between the moon's effective temperature of 270.6 Kelvin and its actual mean temperature of 220 Kelvin. Participants explore factors influencing this difference, noting that atmospheric effects are minimal due to the moon's lack of a significant atmosphere. Albedo, or the reflectivity of the moon's surface, is highlighted as a crucial factor that impacts the actual temperature but is not adequately accounted for in effective temperature calculations. A participant mentions needing to adjust the albedo value to approximately 0.34 to align the effective temperature with the observed mean temperature, while the moon's actual albedo is around 0.11. This indicates that albedo plays a significant role in the temperature discrepancy on the moon.
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Why is the actual mean temperature of the moon so much lower than the effective temperature?

NASA lists the effective temperature of the moon at 270.6 kelvin.
The mean temperature of the moon at the equator is 220 kelvin.
With no atmospheric effects, why is the surface temperature so much lower than the effective temperature predicts?

Rephrasing for clarity:
What factor is NOT part of the effective temperature formula that so dramatically affects the actual temperature of the moon?

Normally one would say atmospheric effects, but the moon effectively has no atmosphere - certainly not enough of one to cause this big of a discrepancy.
 
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ExcessRed said:
Why is the actual mean temperature of the moon so much lower than the effective temperature?

NASA lists the effective temperature of the moon at 270.6 kelvin.
The mean temperature of the moon at the equator is 220 kelvin.
With no atmospheric effects, why is the surface temperature so much lower than the effective temperature predicts?

Rephrasing for clarity:
What factor is NOT part of the effective temperature formula that so dramatically affects the actual temperature of the moon?

Normally one would say atmospheric effects, but the moon effectively has no atmosphere - certainly not enough of one to cause this big of a discrepancy.

I think Albedo, i.e. how much of the radiation is reflected by the body, is ignored when calculating the effective temperature.
 
Actually, the two formulas I have seen that determine the effective temperature use albedo as a factor - I should have mentioned that.

I have to plug in an albedo of around .34 for the moon to come up with an effective temperature of 220, whereas the moon has an albedo around .11
 
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