Visibility of Luna and Lunar Crescent

Si"At = Sinpstnq +C6e,Cot6,CotH,
(21.11)
Th. cordiG for rhe tuirg ! siring d:
AT, =
(2.7 l8)
Adding these A?_, ifto rh. appropriarc I, givcs ibpDvcd valu.s
tunhq inpov€d r:lucs catcutal. $e @.dinaas of rhc Ss fd
&d rcpeat (2.6. r 2) ed (2.6.1 8) ro obrain lh. UT for d€ wau.
lor Ue Moon rhc i$uc is mt! complided s af€.r of panlta h signiticor.
Th€ !ffrr ofrcfddjon h ro dcc'le the anirh dist ne !o rhar the objed is visibl. dei
if n is th@Edcat gonc dom $. horizon bln rhe aflccr of pa6 d b to inc@sc rhe zcnid
d6t fte e lhe obj.cr is wlt .hovc lhc horj@n dd n a!,p.4 ro Mvc et (or rcl n*n
still), Thus for fie Moon the si&dard attjtude is Civcn by:
ao =E - 0-2n5. t -10134''
(2.1.te)
qb.G r is dc pa&Id of rb. Moon eivd byi
(2.7.20)
p s $. g€@eniric dist ncc oflhe
obsrvr &d X, rhe g@ce ric dislece otrhe Moon, p
\2.7.21'
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