Which Calendar Should Determine Ramadhaan?

Which Calendar Should Determine Ramadhaan? As can be seen, even predetermined calendars which are calculated according to precise measurements require some specific methodology, such as conjunction, moonset-after-sunset, or some other precise measurements. The differing methodologies will result in different calculated calendars. The question arose among Muslim scholars: should Ramadhaan, and other religious days of fasting/celebration […]