Pradosha Vrata, also known as Pradosham, is a sacred day dedicated to Lord Shiva in a Hindu lunar month. Pradosh falls on the 12th day a Hindu lunar fortnight. There are two Pradoshas – one during the waxing phase of moon (Shukla Paksha) and another during the waning phase of moon (Krishna Paksha). In February 2009 Pradosha dates are February 7 and February 22. The Pradosham on February 7, 2009 is also known as Shani Pradosh as it falls on a Saturday.
Fasting, special pujas and rituals dedicated to Lord Shiva and Parvati are observed on the day. Most pujas and rituals are performed during the twilight period (around 1.5 hours before sunset and 1 hour after sunset).
Fasting from sunrise to sunset is observed on anyone of the Pradoshams in a month. There are also many Shiva devotees who fast on all the Pradosha days.
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