The total lunar eclipse from October 28, 2004, was observed by AMSU-B (Advanced Microwave Sounding Unit - B) on NOAA-15 during a couple of minutes of each orbit around the Earth. From this unique vantage point in space it could provide disk-integrated, effective lunar temperatures at lower frequencies than employed in most previous observations of eclipses, in intervals of 100 min. The relative changes in brightness temperature were 6.4±2.1% at 89 GHz and 16.6±2.1% at 183 GHz. This trend of stronger temperature drop at higher frequency was expected on the basis of a new radiative transfer model simulating the global brightness temperatures. Our measurements disprove two results published in the past, but they confirm the claim made before that the changes are similar at the center and for the whole disc. In terms of precision they are comparable to those carried out in the past with radio telescopes on ground.