“Thursday [Nov.14] is the Day of ‘Aashooraa’ – the 10th of Muharram. The Prophet (may Allaah raise his rank and grant him peace) encouraged us to fast on this day to have the previous year’s sins, forgiven. We should fast it and a day before it, or a day after it, to oppose the practice of the Jews who fast on this day alone. [Arabic message from the Muftee of Saudi Arabia.] – http://www.bakkah.net/en
Other countries please check and confirm with Local Moon sighting ”