Visibility of Luna and Lunar Crescent

ofits si8hling greatly vary not only longiludinally on rhc globc bd de[Md o. $e tarnude
ofplaces. ThB an obedarioMl lunar c.lendar may vsry along the se logirude. Apart
iron calenddcal aspects $c pobl.m ofsighting v.ry yolne cGsc€nt is on€ of lhe mosr
excitins fld challenging obseFations for both $c adareur md rhe pma€$ioml
asionofre6 Besides, thc pcdicion of fic vkibilily of a paniculer .erv cEsenr ar a
panicular placc is a long and inter.sling cohpuhrional exerci$ Thc sane was clliad
as early as rhe dedieul times by the grelr ostonomcs Al-Khwarizni, Al Batani. At
Farghani etc (Bruin 1977) Mocovcr. t|t prediclion foL nak€d eye obseivarion ha lwo
noE cohplicated hsues under srutiny rh.laresr esearch. Onc oathese is biologicat.
lhc abililt ofhunan eye to conrfa$ $e dimly illunrinatcd ciesceht in rbe bnght rsilighl.
The olher aspcct h ol physicrl n4lue ofalfiosph.ric conditions ftar c.n b.dtr aoecr rhe
risibilit! and rc contdsr h this \o.k c l'hdk h morc on thc $lrcnoNical asp..rs of
lhe eadiesl siebdrg olthe new luna!.rr$enl dnd ahosphcric €ondnion !.e onb plnlr
Opinions aro diided d tq thc oriSin of$c.llton olcomlins yer6 in an! tofrr
in rhe ARbian l,cninsula. Accordihg to At ttazsi il $anln as soon as $c cni rcnof
Prcph€l Adan nuliplicrl and spRod aouid rhc rw d (Ro$nlhal l9i2. l_mqi t979) A
calehdar sE originated wncn rhe Himyarires adoptcd one sjtn m epo.h lhal marked rhe
b.ginni.B or the eigns ol Tubbn. Cenerally it is b€licrcd thal lhc pnctice of 12 lunar
nontns lo a year cxisbd in pre,lslahic Ar.b c.lend.rs since rhe rime ofconsrruclion of
Kaba b) lhe prophd Abnham a.d conrinued in Islom (llyos. 1994). The namcs ol$c
months and thcii sequenc€ Mre thc snc as tho* used in lhc cuiicm tslamic lunar
calcndar Ibllowed by morc rhah on.lifrh of$e roralFopulation ofrhc world.
Fom historic pcspecrire lhc inpon.nce ofrhe lunarcalcnda in lbe pE-lslamic
AEbia $€s the pilsrimage ro Kadba (Haj) rhar talls in $e monrh orzul-hajjah, rhc l2'"
nrnlh oflhe hlmic and prelslamk lunai calendar, Althoush this event was a puelt
religious evenl. il was also inportlDt ior kadc and busincss wnb b$ ol goods
exchanging bands. ll w6 this econonic rcrivil, $ar w6s badly anected as rhe lunarrear
ad!dced llxoush *&ns. PEcufnent ofcop and rhe ovailabilir) or.ac f.,ul anim...
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