This test samples the variations in each mode during during conditions of changing thermal environment. Time sequences for each spectroscopic mode will be taken at 5 different times. This will allow us to examine the effect of thermal drifts in different thermal envi- ronments. Measure the image drift from slit to detector within STIS for each of the spectroscopic observing modes. This test will show the required frequency of readouts.
Goals are dependent on any additional wave- length accuracy needed by the observer.