The lunar month of Margazhi (Dhanu, Mārgashīrsha)

Just marking this very special lunar month 16 Dec to 13 Jan - my efforts at briefly collating several aspects of the month.
# Krishna says - (Gita, 10/35)
बृहत्साम तथा साम्नां गायत्री छन्दसामहम् ।
मासानां मार्गशीर्षोऽहमृतूनां कुसुमाकरः ॥