Results
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•Numerous hot spots
–Correlates well with with previous mid-IR meas.
–Cools more slowly than surroundings
–Correlates and anti-correlates with visual albedo
•4.3 µm brightness T ~20K higher than Mid-IR
–Effective emissivity ~65% higher than mid-IR
–Caused by surface roughness and cratering?
•Warm temperatures contribute more than cooler temperatures to the beam integrated flux at the short wavelengths on the Wien side of the blackbody curve than at longer wavelengths were the response is a less steep function of temperature
Conclusions:  The Midcourse Space Experiment observed the 27 September 1996 lunar eclipse at 4.3 µm.  The observations resolve the lunar disk with a ~45km footprint.  Numerous hot spots were detected as were extended features with brightness temperatures significantly warmer than their surroundings.  The hot spots and features correlate well with previous mid-infrared measurements.  However, the 4.3 µm brightness temperatures are, on the average, 20K warmer than those derived from mid-infrared observations. Vogler et al. account for the observed decrease in brightness temperature with increasing mid-infrared wavelength for the full Moon as due to surface roughness, which they represent by a distribution of parabolic shaped craters across the surface.  In the simple example they give, a low spatial resolution measurement of the lunar surface cannot resolve the individual rough features, which tend to be warmer than their surroundings.  The measurement beam integrates over features with a range of temperatures. Since the blackbody energy distribution is a steep non-linear function of temperature for the shorter wavelengths, the result is a higher brightness temperature as the warmer areas will contribute much more to the average.  The contribution is roughly linear of temperatures at the longer wavelengths, resulting in a lower brightness temperature.