Visibility of Luna and Lunar Crescent

Chapter No.5
APPLICATIONS
Durin8 rhls work lt ls obs€oed thar since th6 Babytontan eE flt recenty a
nomber ol pr.diction crltsrta, mathehatic.t .s we as obsewational. were
developed ro detemln€ whon the new tunardesc€nl woutd be flrsr seen tor a gtven
rocataon. as tho fist appea.ance ot new tunar crescent marks tho beginning ot a
new month in obseryarionat tunar catendaE thele crireria and modets are
sagnirrca.t fo, calendaicat purposes_ wh€ther an actuat obsrya ohat tuna,
carendar, like the tstamlc Lunar catendar, ui izes lh.se crireria tor arangtng its
carendar of not rhe36 c.trerta provtd6s a €uidance for both teslhg an evtdenco ot
crescenl si8lting by common peopte and tracing down ihe dares ot a catendar jr
hErory where app.opriate dates are not we recoded. Ttus the main uti ty oi the
prediction c terta tor the eartiest visibiny of new crescent ts to regutate tho
obsefr atlon.l lunar catendaf .
Although ftrst order approximations, rike Anrhmetc LunarCatenda, thar are
oased on lh6concept of LeapyeaFand rh6 averag6 mooon or rhe Moon fave been
in use, Nluslims hEve been to owing dctuat si€htng o, crescenls ar teast tor the
monrhs of fas n8 (Ramazan) and pitgnmage (z hajjah), the acruat moion oi the
Moon varies grea y due to vartous tactoB whtch causo rne obseryarionat catendar
lo be ditfered froh the arithmelc c6t6trdar.rh6 Catendars if based on a prediction
c lerlon llko thar otya op or ihe one devoloped In this work are rhe cto56t to rhe
ob*patlonat catendai In this chapter, wecohp6rethese carendaBwith th€ a.tual
obseryatronat catend6r in pracrice In paktstan tor th6 years 2ooo ro 2OOz, ft ts
found rhst on avorage 93.7% obseryadons ,16 ac@rdtng to rho yalop,s o_v6tue
t72