1. Cold Case Model
Hot Case Model
GPS
LMC
GPS
LMC
Launch
4.7 QCL LO Cryocooler OFF
Ascent
4.7 QCL LO Cryocooler ON
Predictions of the Cooling fluid temperature at the inlet of the radiator for two environmental model cases. The parameters for the two cases are in the next slide
This model assumes that the cryocooler used to cool the 4.7THz QCL is turned ON for ONLY 2 hours during the second day at about 2 hours prior to changing attitude to look at the LMC. It is turned OFF when moving to the LMC
Cooling system input power assumptions: W when 4.7 THz is NOT in use, 500W when it is in use.

2. Hot and Cold cases simulations
Hot Case
Float altitude
120 kft
Latitude
70° S
Date
Jan 31st
Dec 21st
Solar Flux
1392 W/m2
1397 W/m2
Albedo
63%
95%
Earth Flux of
156 W/m2
250 W/m2
For both Cold and Hot cases runs the model simulates dynamically prelaunch, ascent, and first 48 hours of flight with predicted gondola attitude and telescope elevation