Re: practicing with sextant on land
Hah, looking at some of the other tables available on milutin's link:
"Temperature and Pressure Factors for Refraction (Corrected Refraction = Tabulated Refraction x Factor". I like corrections on the corrections :P The takehome lesson seems to be, never shoot stars near the horizon. Above 25°12', the correction is less than 2 minutes, and above 45°33', the correction is less than 1 minute.
"Moon's SemiDiameter Corrected for Augmentation", which is indexed by Alt and HP, followed by "Latitude Correction to Moon's HP". Awesome. You use your latitude to correct the tabulated HP, which you use to correct the moon's semidiameter, which you use to correct your sextant altitude (which you use to calculate latitude!) Takehome lesson: the moon is not worth it.
That said I'm now getting excited to try the Lunar Distance method for calculating time. I guess I'll wait until the next firstquarter, though. One advantage is that it's sextant practice that doesn't require a horizon.
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s/v Laelia  1978 Pearson 365 ketch
s/v Essorant  1972 Catalina 27
Last edited by AdamLein; 04092012 at 12:29 PM.
