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    Re: Exercise #14 Multi-Moon LOP's
    From: Mike Burkes
    Date: 2008 Nov 17, 18:03 -0800

    Hi Peter, pretty close I got 14d 15.4N, 142d 53.3E.
    Mike Burkes
    On Nov 16, 1:19�am, "Peter Fogg"  wrote:
    > Federico you asked, on 8 Aug last: "Any comments?"
    > Basically agree. �Using all of the sights I derive, at the time of the
    > first, a probable position of:
    > N14d 15.3' �E142d 53.2'. �Have allowed for the ship's movement while the
    > upper limb of the moon is being observed. � As Greg Rudzinski points out,
    > the ship is steaming at 080d, while the position line extends towards 069d;
    > fairly similar.
    > Have plotted these sights and compared them with the calculated slope. �They
    > are evidently very consistently good observations, showing little spread.
    > Since the apparent movement of the moon (or any celestial body) as it
    > rises/falls is an arc, extending the time-spread of the multiple sights
    > beyond about 5 minutes, as here, could lead to those at either end being
    > less reliable.
    > Adopting 19h 08m 00s and 65d 54' leads to an azimuth of 159.1d and an
    > intercept of T0.6, which may be a slight improvement on the sight taken at
    > close to that time, #4: 19h 08m 06s, Hs 65d 55.0' ? �At any rate, plotting
    > them reveals that there are none (excepting perhaps those at either end, for
    > the reason above) which need be discarded. �In this case an average should
    > give a good result.
    > Jeremy posted the problem in NavList 5416 on 13 Jun 08; mind his corrections
    > which followed soon after.
    > On Fri, Aug 8, 2008 at 9:34 PM, Federico Rossi wrote:
    > > �Hello everybody,
    > > I was browsing through the exercises that Jeremy kindly posted on the list
    > > back in June. Today I was working out exercise 14 Multi-moon LOP's and I've
    > > seen there was no solution posted (if I'm not wrong), so here's mine.
    > > I've averaged the sights and obtained a Hs of 65 deg 59,8' at 09 09 14 UTC
    > > (or 19 09 14 ZT). This yields to a calculated altitude of 65 deg 55,5' (I
    > > use the haversine method and Norie's tables 'cause I like working the old
    > > way) and to an intercept of 1.3 NM forward. The azimut is 160 deg. Moving
    > > back the LOP to 19 00 00 ZT and assuming the intersection between this LOP
    > > and the course made good as the most probable position I got a fix at 14 deg
    > > 17,0' N 142 deg 58,5' E.
    > > Any comments?
    > > Federico
    > �Slope.pdf
    > 785KViewDownload- Hide quoted text -
    > - Show quoted text -
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