Midcourse Space Experiment
Calibration of MSX created a challenge for designers of the experiment, as baselines (measures of what occurs naturally) did not exist for the bands it would be observing under.  Engineers solved the problem by having MSX fire projectiles of known composition in front of the detector, and calibrating the instruments to the known black-body curves of the objects.  The MSX calibration serves as the basis for other satellites working in the same wavelength range, including AKARI (2006-2011) and the Spitzer Space Telescope (SST).