Visibility of Luna and Lunar Crescent

both rhe Sun and thc Moon. Thse cor€ct d eclipiic coordi.ates of fie Sun and the M@n
@ lhen arNtomcd into Equtodal @dinal6 a, the RiSht A*nsion 4d 6, lhe
Delination. In order lo g.r th. tical Hodental coo.dimt€si Ahitude and Azimuth, of
ihe Su ed the Moon, rhe ob*frers rcft$rial cooidinale dd the t cal SidftalTime
(dcfin€d as lhe L@al Hou AnSle oflh. Equinox) aE rcquiEd. A simple alSorilhn lcrds
ro fie Greensich Mean Sidereal Time (GMST).r lhe Oi'Unilesal Tinre for any given
dsle. AddinS lhe local longilude 1o rbis GMST erv.s
1he r,cal Md Sidereal Tihe for
0i' Uhiv.sal Time for any eiv.n dale is oblained. finally to gct $€ Local SidcealTine
for my nonent of the day day be obtain€d keepids in mind the f6ler pace of $e
Oncc lhe tical SideEolTihe ofany moncnl is looM the Hour Anele oflhc any
obj*t is oblained. The local Euatorial coordiiarcs s, th. Hou Anele ed 6. the
declinalion,lead to the Altnudc (heiehr obove lh€ holizon) dd Azidu$. n@ poiilsol
tine @ imporrant lor lhis slldy. when m objecl is al lhe local meidian (i.e. TEnsi().
when rhc objecl rbes ind when an object srs.
Thc time oa tEnsil may be calcularcd using rhe Hour Angle to be eo, or rhe
co.siderinS rhe tical Sidereallime 1o b.lhe Righr Ascension offte objccr. The *timate
olthispointoflimc can b€ inpoled uing an ireraive pccs (hal inmlves Eadjustihg
the lime arsumena'lo be lhis approximatc tim€ and rccalcuhting the coordinates offie
objd at thisdme argumehr.
ConsiderinS Hour Angle t io be 9Oo or 6i" approxidare rihe of rhe rkins
(n€earive t, o. the se(ins (posnive 14 ae obraincd. R*rlculatins $e rimc dsunenrs
tor approxidale limes of thcsc eve s $c coodi.Eres ofrhe object de deremined again
ad the b.lter approximtion of$e inct oflh€s denrs ac ob!.ined. This giv.s the
risins a.d the setins orthe cenres ol$e objers (rhe sun and the Moon) thar can b€
adjnsred |o s€t $e actual isins (the first app€arance of the weslem limb of the objec,
.nd acrual s.tti.s (homen! of dcappe&ance ofrh. cded linb of the objsrl.
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