Planets - Effective Temperature vs Actual Temperature

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SUMMARY

The discussion centers on the discrepancy between the effective temperature of the moon, listed by NASA as 270.6 Kelvin, and its actual mean temperature of 220 Kelvin. The primary factor affecting this difference is albedo, which measures the reflectivity of the moon's surface. While effective temperature calculations typically incorporate albedo, the moon's actual albedo is approximately 0.11, significantly lower than the 0.34 needed to reconcile the temperatures. This indicates that albedo plays a crucial role in understanding the moon's thermal characteristics.

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  • Understanding of effective temperature calculations
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  • Familiarity with basic planetary science concepts
  • Awareness of NASA's temperature data for celestial bodies
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  • Research the role of albedo in planetary temperature calculations
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Astronomers, planetary scientists, educators, and anyone interested in the thermal properties of celestial bodies, particularly 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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