Moon calendar for cleaning windows: December 2030
The old moon calendars name good days even for cleaning windows. You clean with a waning moon, and preferably on a day when the Moon is in an air sign.
Good days
Tue 10 (Gemini), Wed 18 (Libra), Thu 19 (Libra), Fri 20 (Libra)
With a waning moon in Gemini, Libra or Aquarius, the panes are said to dry without streaks.
Better not
Sun 1, Mon 2, Tue 3, Wed 11, Thu 12, Fri 13, Sat 21, Sun 22, Sun 29, Mon 30
When the Moon is in a water sign, in Cancer, Scorpio or Pisces, the panes are said to streak more easily.
The Moon's position is computed for every day at noon, Central European Time. The rules are tradition, as the old moon calendars hand them down, not a promise. The whole calendar: moon calendar.
Other months
2026: October · November · December
2027: January · February · March · April · May · June · July · August · September · October · November · December
2028: January · February · March · April · May · June · July · August · September · October · November · December
2029: January · February · March · April · May · June · July · August · September · October · November · December
2030: January · February · March · April · May · June · July · August · September · October · November · December