Thermal asterism

Ocean surface temperature AYHRR, ATSR-2/ERS-2, AATSR/ENYISAT, MODIS/ EOS-Terra/Aqua, AMSR-E/EOS-Aqua, OCTS/ADEOS. Spaceborne system EOS/Terra is equipped with radiometer ASTER to measure thermal radiation and its reflection from the ocean surface, spectrometers MODIS and MISRC, as well as MOPITT and CERES instruments to record pollutant and energy fluxes, respectively. 

The electron transfer reaction between P and BPh is slightly/aster at 80 K than it is at 295 K, indicating that it does not require a thermal activation energy [131]. This agrees with earlier observations that charge separation in the reaction center occurs with a high quantum yield at temperatures as low as 1 K [149]. 

Figure Al-15 shows an example of this phenomenon, often called thermal asterism because of the radial direction of the diffuse streaks. This photograph was obtained from aluminum at 280°C in 5 minutes. Actually, thermal agitation is quite pronounced in aluminum even at room temperature, and thermal asterism is usually evident in overexposed room-temperature photographs. Even in Fig. 3-6(a), which was given a normal exposure of about 15 minutes, radial streaks are...

Fig. Al-15 Transmission Laue pattern showing thermal asterism. Aluminum crystal, 280°C, 5 min exposure.

Users of ASTER data have found decorrelation stretching to be particnlarly effective in image display. The stretch is effective whether the bands used are in the Visible, the SWIR, or the thermal IR interval. The three ASTER scenes in Fig. 11 (again, of an unidentified area) show the effects of a DS. 

Fig. 11 Decorrelation stretch of visible, SWIR and thermal IR images from ASTER...

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