Visibility of Luna and Lunar Crescent

notion s iounded in thc lue €ph€mdjs ih.y pEpaed (Fat@hi d al, 1999). Ac@rding
lo lheF $udies it is pointed out lhal the noonset-su$et lag atone.ould nor have been
used as lhc visibilily dit.rion by rhe Babylo.ids. BabytoniaN sysren had $c tollowi.S
rlohedrior rL, - moon*r tasrme rin deCrees,,S) - conninr
In vdious $ud,cs lhe vrtue of$e conqant rs dedlce ftum | 7 degFes lo anyrhere
&ound 2l d.8R<. Hokercr on lhe basis ot rhc confimed 209 positile siehlings fmnl
,car .567to yetu .77 rhc \atue of rhc .o6ranr is deduced ru be 2l degrees (Far@hi cr at,
r999).
Sinilarly hosr of$c modcm aulhou arribule rules ot th€
ttpe lo fie Muslinrsand A6bsofmedieval tinrcj
''Th. t.latie attitLt! UnCy) > Ao ahd koans.t,ulet td|tin >.t2 nin cr_
lr has been indicared lhar Mrslins. reatization thar rhe Eddh-Moon dhlancc laries during
one comptet€ cyctc ot tlhar ph.ses and lhe hininuh moons€r lag lime considercd b,
^Ebs vaiied fiom 42 ninures for Moon ar perigee.nd 48 ninurcs for Moon at aposee
Thonsh lhis -nrle of thunt. is no4 sophisricated 6 compNd ro $e one
art'buled ro |hc Babylonims sli jr does nor povidc rhe complere prcrup of rhe cffons ol
Arabs ad Mulin' h $c hedirwt ines exl€trir ur ofAolemaic sy{en ed rhe
spherical risonodeq devetop.d b, Ambs lead to the L!n& Rrp€.es flnclion (bat
depends on locatbritud. ofrheptace ofobrNadon dd lbe c.testiat to,gilude ofthe srn
and lhe Mooh) 6 eartr as lO cenrury AD (Bruin t97?)
Babylonie crirerion h indeed lery sinplc for praclcar purPoses and is supposed
to have ben cmpirical in
no significdt chahgc in rhh rill