Our sources contain problematic lunar statements.

Some examples:

  • It is widely presumed that the New Moon can be seen 6 hours after the Molad.
    • See my Molad of Tisrei Study 
    • In fact on average the New Moon is seen 30 hours and 44 minutes after the Molad. The earliest it was ever seen was 9 hours and 8 minutes after the Molad
  • It is claimed that from the time the Old Moon is last seen until the New Moon is first seen is 24 hours.
    • The Old Moon is last always seen just before sunrise and the New Moon is first always seen just after sunset. The minimum such period is 6:00 AM to 6:00 PM but this is too short as seen in the paragraph above.
    • Thus the minimum possible period is approximately 36 hours, much more frequently 60 hours, and sometimes 84 hours.