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Frank Wrote:
> Notice how averaging would help you here. The errors in the LD's are -0.3,
> +0.7, -0.4. And the average is [drum roll, please...] exactly ZERO! This is
> partly accidental in this case, of course, but you will find that the
> results are almost always better when you average a set of three to five.
> Averaging the errors after the reduction is not quite the same as averaging
> the sights and times before reduction, but it's nearly so. And just to
> reiterate, this was the normal historical approach.
>

What is the traditional means of averaging?  Do you average the time
and then the LDs and just do one reduction?  I have never averaged
sights really except to reduce 3 sunlines, plot them, and find a
midpoint.

> By the way, if you want to think about lunar distance observations
> differently, each lunar generates a line of position, which you could plot
> on a chart just like any other LOP. But unlike standard altitude LOPs, an
> error of 0.1 minutes of arc in a lunar distance observation implies a 6 n.m.
> error in the lunar LOP. One advantage is that you can shoot lunars when the
> horizon is hidden. Cross two lunar LOPs and you get a rough position fix.

I would like to try this, but am not sure how you do it.  Lunars are
my weak point in Celnav, and I can
hardly get them shot and reduced, let alone do something exotic with
them as make an LOP.

Jeremy
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