I would like to test a telescope with a Moon observation. It is a low spectrometer-imager at 110-300 GHz with a resolution of 4 arcmin@150 GHz.
Is there any scientific target that concerns the Moon with such an observation?
Millimeter and sub-mm observations (110-300 GHz = 2.7-1.0 mm) are sensitive to the thermal emission and provide a brightness temperature of airless bodies like the Moon or asteroids. The radio emission is from just below the surface/skin of the body (down to $\sim10\lambda$ so ~1 cm in this case) and so is also sensitive to the thermal inertia and conductivity of the surface and regolith. A paper discussing sub-mm observations of the Moon (which is freely available) is Pardo et al. 2005.
A major issue with observation in the mm/sub-mm is atmospheric absorption due to precipitable water vapour (PWV) as seen in the plot below which shows the atmospheric transmission in the mm/sub-mm at the summit of Mauna Kea (~4100 meters):
Note that the worst case shown (in red) with 5mm PWV is already a very dry atmosphere that is rarely found even at other high mountain sites; sea level sites could easily have 50+mm of PWV. This could make these type of measurements very challenging.