It had to do with the predicted and actual surface temperature of the Moon. (theinconvenientskeptic.com)
Upgrade the station and do day / night 360 degree infrared measurements, grid surrounding surfaces with actual surface temperature measurements in multiple samples per year etc... That might be worth 100K per station. (wattsupwiththat.com)
Further processing is needed to remove the effects the atmosphere and account for the characteristics of the surface to turn this into an actual surface temperature map. (sciencedaily.com)