I wish I could say I told you so, but it wasn't me who found the references. I'm too lazy. Good work,
Macalaure.
You might also consider,
Legate, whether Saruman would have
needed to practice astronomy since he was a Maia, and likely already knew everything he needed to know about the locations, movements, etc. of the stars (he was a bit of a knowledge junkie). If true, it makes it all the more likely that what Saruman was doing was astrological in nature (since we are evidently distinguishing between astrology and astronomy
).