Averaged 4.3 Map
9
| The 4.3 µm image of the
average of all the measurements taken during the last 20 minutes of
totality. The image has been rotated
counterclockwise by 90° to bring it into closer alignment with the visual
image of the full Moon in view graph 9, which is included for comparison. |
|
| The brightness
temperature on the Moon drops steeply during the partial phase of eclipse
from about 380K to ~200K for the sub-solar point. Thereafter, it declines less steeply to
~175K by the end of totality8. Fairly large local contrast exist. For example, Shorthill, Borough and Conley9
determined that the lunar disk temperature dropped to below 200K during the
eclipse of 13 March 1960 and that Tycho was about 50K warmer than its
surroundings. Saari, Shorthill and
Deaton10 produces an isothermal contour map of the
Tycho region that also had about a 50K contrast with the crater at a
temperature of roughly 210K and the surrounding at about 160K near the end of
totality. These temperatures are in
qualitative agreement with the 8.3 µm image where anything that is not black
(saturated) should be cooler than 195K; but are about 20K lower than the
values observed at 4.3 µm |
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| _______________________ |
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| 8Petit,
E., 1940, “Radiation Measurements on the Eclipsed Moon,” Astrophys. J., 91,
408 – 420. |
|
| 9Shorthill,
R.W., H.C. Borough and J.M. Conley, 1960, “Enhanced Lunar Thermal Radiation
During a Lunar Eclipse,” Pub. Astron. Soc. Pac., 72, 481 – 485. |
|
| 10Saari,
J.M., R.W. Shorthill and T.K. Deaton, 1966, “Infrared and Visible Images of
the Eclipsed Moon of December 19, 1964,” Icarus, 5, 635 – 659. |