NavList:

Joshua Carty you wrote: "What was my latitude? I realized I wasn't sure how to do this after the sight! Can you all tell me how to? Are there different ways... And how about longitude? Since I know the time when Kochab was aligned with the north star, does that give me a good longitude, too?"

I’m assuming that you’re assuming that you must have been looking close enough to north, to treat this as a Meridian Passage calculation, because Kochab was directly below Polaris.  The trouble is, in this case Kochab is below Polaris so it’s on the opposite side of the North Pole to your own meridian.  One method to solve this is to use the formula Latitude = 180° – (Dec Kochab + Zenith Distance) where Zenith Distance = 90° – Height observed. 

Now HO = HS +/- Inst error, – Dip, – Atmospheric Refraction = 31° 38’ + 0', -3.9’, - 1.6’ = 31° 32.5’, Dec Kochab = N 74° 03’, and ZD = 90° – 31° 32.5’ = 58° 27.5’

Therefore, Lat = 180° – (74° 03’ + 58° 27.5') = 180° – 132° 30.5' = 47° 29.5’N
I’ve a feeling that Frank might say that if you’ve got your head screwed on correctly, you only need one formula.  Unfortunately, mines getting a bit loose.  Doing celestial calcs after 21:00 UTC, it keeps falling off onto the table.

In theory, you might get a longitude with a correct time, but in practice you won’t for two reasons.  Firstly, Dec Polaris is not exactly 90, so it wiggles around the Pole, and its azimuth depends on its LHA, which depends upon the longitude you’re trying to find.  You could say “I’ll just watch Kochab very carefully, and I’ll know it’s due north when HS is a minimum", but that’s not practical; HS will be within one minute of arc for several minutes of time.  It’s like this ‘hang time’ we’ve recently been talking about except this time we’re looking for a minimum altitude rather than a maximum altitude.

Well-done on advertising Kochab.  These days, with the light pollution near me, it’s the only way I can just make out Ursa Minor and, if I’m lucky, Polaris.  DaveP