Visibility of Luna and Lunar Crescent

On lhe bais ofthh dlatioo wc tlcnre th. visibil,ty p.m.t€r v, 6 follows:
v
e = QRCV - ('-O.35lg$7W3 + 2.22207 5057W2 - 5.422643U t/ + 10.4341759) / l0
(4 4.2)
Our model for .adi.sl visibility of n w ls& *s6! ir that if rp > 0 (w @ll the
visibility paEmctcr v, in (4.4.2) s th. r-vtl@) lhc ceml moy be lisiblc withonl
opdcal aid olheei* noi Applting this €o.dition on thc dat set ued in chaflet I &d in
lhb chaptcr qe present thc rsulls obtained for whole data set of463 cd* in d.ltn
colunn of table in appe.dixlll. Fid fd .ss when rhe visibilily is claiocd wjlhoul
optical aid in odcr of inccGing r-ralrcs @ sho$ in 1abl. 4.4-1. Oui ol0tcs cses
only I I 66 d4iatc ton ou nodel. our of rhese I I c6es 8 de coosisteni sill the
nagnitud€ conlrast 9 arc consisle.t wirh Yallop s crirerion and 8 ats consislcnt Mth the
Lund Rip.o6s Law, Tbe oberyaiion Nnbes 3E9,455,274, 341 dd 316lhal d.viale
from lhe Lmr Ripen.$ I-aw, ihc Yallopt crilerion ed 1be Dagnnude conlrdt d also
negrdve i. our modcl. How€vcr the obseorion nwber 4161hat is negalile in orher
models is allowcd by ou!nodel. ille Een is th.t in this ce ARCV b redonably hish
(9.41 .l€g@9. Txe widdi h small (eund la @ sondt bur |hc M@. is rcry close ro
perige s closr ro $e Efih.
In fisuE 4.4.2 the minima of each visibilily cw. is joincd resulrins inro o
nFi8ht linc stich $nen .xlodcd inr.e.l tn€ oigin of rhe (r. t) c@rdjnde stseo. The
srope of rhis linc is found ro b€ (lh + sys -) 9-3t5 ot t'/s - 4.)15. This lqds ro a Dodi6.d
''b*ttine" of cesenlvisibility a:
,3 = -=-i:
s1:s+4.3(Ts+LAC)
rBin conp&ison ro l(2.25)rh panoflAc in
(4.4 )
9.3
l(2.163)rhpanofLAG
besl tih. of crcscenr visibiliry is give.
t62