My first problem was that I took PBB's stated elevations of Sirius, Rigel, Procyon, et al, as fact for that is where I had gotten the stated elevations. If Printy's program is correct, then PBB data is way off the mark.
My second problem occurred when I made approximate stellar locations (azimuths) via a star map showing locations of Sirius and Rigel at various times for 24 October. I knew that the locations were approximations and had stated so in the blog post. But in retrospect, it was not accurate for 1968, even for approximations.
Tim Printy provided via email the following chart for Minot, ND for 24 Oct 1968. The times listed are for local, central daylight savings time. Tim's elevation numbers are rounded, but his information would be much more reliable than what was listed in PBB.
Based on the above, the diagrams for Sirius and Rigel, as seen from N-07, would be:
The revised diagrams provides a visual that tends to support Tom Tulien's claims that Sirius would have been too low above the horizon for Isley and O'Connor to have seen it. Further, Sirius would have been a little more than ESE of their location.
What could Isley/O'Connor have seen due east of their location (5 miles north of N-07) if not of Sirius? Procyon was visible close to due east (azimuth of 94), elevation 12 degrees at 0200 hrs. I have to wonder if such a star as Procyon would have attracted much of their attention, but it does change locations from east to southeast over 4 hours and stays in view for the same length of time.
With that said, Sirius and Rigel do come into play while both Jablonski/Adams and Isley/O'Connor are physically on N-07, roughly between 0300 and 0500 hrs. This still raises questions in my mind as to how accurate were the plotted locations that each individual had annotated on their AF-117s.
A review of William Smith's AF-117 in coming soon.