This uses the approximation described in the
lunar phase wikipedia page, i.e.
the number of days since 1900/01/01 modulo the length of
a synodic month (29.530588853 days)
Examples
day_in_synodic_cycle(Sys.Date())
#> [1] 25.3014
This uses the approximation described in the
lunar phase wikipedia page, i.e.
the number of days since 1900/01/01 modulo the length of
a synodic month (29.530588853 days)
day_in_synodic_cycle(Sys.Date())
#> [1] 25.3014