Navratri is historically celebrated over the first nine nights pursuing The brand new moon during the Devi Pada (the quarter after the autumnal equinox), which is ordinarily called the Sharada Navratri. वन्दे वाञ्छितलाभाय चन्द्रार्धकृतशेखराम्। वृषारूढां शूलधरां शैलपुत्रीं यशस्विनीम्॥ Apart from spiritual point of view There's a scientific overview of https://baglamukhi67642.targetblogs.com/23913573/about-navratri