Table 9 Onboard calibration for FTS-2

ILS laser sphere

X

X

ILS stability because the PFT (once per 6 days)

Solar diffusers (both sides)

X

X

X

Radiometric response degradation (one side per orbit, the other side per 3 months)

Lunar calibration (Park to target)

X

X

X

Radiometric response degradation (per month, + 7° waning near Full Moon)

Deep space

X

X

TIR onboard radiometric calibration (2 times in dayside, four times in nightside orbit)

Blackbody

X

X

TIR onboard radiometric calibration (2 times in dayside, four times in nightside orbit)

Phase transition cell

X

X

Blackbody thermometer verification (if necessary)

FOV camera

FOV confirmation (2 times per sounding in dayside orbit)