DETERMINING the first day of the new lunar months on the Islamic calendar are tense times for the Nahdlatul Ulama (NU) and Muhammadiyah organizations. As it turns out, it is not an easy matter to celebrate the festival of fast-breaking (Idul Fitri) holiday at the end of Ramadan on the same day. NU believes in using the method of rukyat al-hilal or sighting the slight crescent moon with the naked eye or through binoculars. Meanwhile, Muhammadiyah