Visibility of Luna and Lunar Crescent

Fig. No. 5. L7: Mesuemcnr of Length for Cterent of Mav 28. 2006 as pholoeraphed rr
Xffiltr UtoveElty obsefrd@ry.
'the dlta aor the obsiedcEscehl lenglhshoM in |able 5 12 and the cbart i. fig
5. L? shows inlqesrine paficn. Clain d by Schacfer (Sch@fer, l99l ) fie crc$ent lcngh
is a sn@$ fiDction of elonSatio.. but lhis drE er sho*s a tMd that cl*lv exhibns
delialion tion oy such sn@$ rel.tion. I]lc dala sdple is snall bnl lheE de lwo
subsets eech having neally sE@th relations, separatelv. b€twcc. lhc crescent length tnd
the €longation. Hovever, rhen consideed s a conbiNd dala sel lh€ obsflatios uith
elongarion ll93 de8lees (by AnFa} l44l de8@s (bv Oner) 1667 degEes (bt
Ralini) md 20.12 degrees (by Qwshi) deviarc Mk€dlv lbm $e apPaEnl snoofi
rclarion exhibiled by the rcsl oflhe dala set Cecchl l€nsths in rhcse four cNs are huch
snallcr thm lhe uend shown by the rcsl ofob$wationsas wellss thcresultsofe&h rhc
mod.ls co.sid€red abovc fot calculaline lhs le.gtb of $e ciesccnl
186