-- from january 15 to february 6 is a period of 22 days.
-- the period of the full cycle of moon phases is 29.53 days.
-- so those dates represent (22/29.53) = 74.5% of a full cycle of phases.
-- that's almost exactly 3/4 of a full cycle, so on february 6, the moon would be almost exactly at third quarter. that's the left half of a disk (viewed from the northern hemisphere).
it would be 5,400n. i hope this !