The term "tithi" is a noun that signifies a lunar day within the Hindu lunisolar calendar. The full phrase "tithi on 11 september 2025" functions as a noun phrase, specifying a query for the particular lunar day corresponding to a specific solar date. On September 11, 2025, the tithi at the time of sunrise is Krishna Paksha Chaturthi, the fourth day of the waning phase of the moon. This is followed by Krishna Paksha Panchami, which begins later in the morning.
A tithi is technically defined as the period during which the longitudinal angle between the Moon and the Sun increases by 12 degrees. Due to the variable speeds of these celestial bodies in their elliptical orbits, the duration of a tithi is not fixed at 24 hours but can range from approximately 19 to 26 hours. For the date in question, the Chaturthi tithi concludes at approximately 10:43 AM Indian Standard Time (IST). Subsequently, the Panchami tithi commences and remains active for the rest of the solar day.
In practice, the tithi that is prevalent at sunrise is generally considered the tithi for that entire solar day for the purpose of determining most festivals and fasts. Therefore, activities related to Chaturthi would be observed on this day. However, for specific ritualistic timings (muhurta) or astrological calculations, the exact transition time is crucial. Any ceremony or event planned after 10:43 AM IST on September 11, 2025, would fall under the influence of the Panchami tithi.
