It's hard to appreciate right ascension this and declination that without pictures. I used a pretty stable version of my html template to capture these screens and then comment on them: pluto page.

I went through the script and added a bunch of comments. Changed some notation to make it more even. There's no remants of Jupiter and Venus there now.

I generate a guess somewhere near the midpoint of the interval, ask for the ephemeris for that time, and pull the row data from the elements we want, in this case, the moon and Pluto.

I lacked the imagination to discuss the main control rigorously tonight. Consider it like this. Each wrong interior guess means you can slide the goalposts in. Eventually you hit a humber where they show both bodies occupying the same second. In this case it is 2458489.99538359. Take a look at 2458489.35, and you see (close to) the same picture from the point of view of the Plutans.

$ pt 3.ut.pl 
$ ./3.ut.pl
Make query number 1? [Y] :Y
row1 is Moon 4h 57m 4s +19° 5.9' 58.6 ER 51.804 −58.490 Up
row2 is Pluto 19h 30m 31s −21° 56.1' 34.700 −27.638 85.830
+ Set
Make query number 2? [Y] :Y
row1 is Moon 23h 50m 34s −5° 55.0' 63.0 ER −12.242 93.887 
+Set
row2 is Pluto 19h 33m 27s −21° 51.7' 34.609 −64.053 148.38
+2 Set
...
row1 is Moon 19h 32m 42s −21° 14.0' 63.1 ER 22.146 16.263 Up
row2 is Pluto 19h 32m 43s −21° 52.8' 34.644 21.516 16.112 Up
Make query number 18? [Y] :Y
row1 is Moon 19h 32m 43s −21° 14.0' 63.1 ER 22.126 16.363 Up
row2 is Pluto 19h 32m 43s −21° 52.8' 34.644 21.495 16.214 Up
equal seconds is 2458517.329784
...
$
[download]

Here's my cleaned up version of the script:

Thanks for the explanation!

Down with the Plutocrats! Up with the Plutophiles....

!