Neil
Well-known member
Sorry to bore the majority to tears, but........
Every now and then I like to practice the art and given that the moon and Jupiter are out at twilight at the moment, I got out my dish of oil and took sights of them both (1 Dec).
I never got round to reducing the sites until this evening and while the moon sight looked good enough, Jupiter was miles out. I used an online site reduction calculator (http://www.celnav.de/sightred.htm) to check my sums, and found that my computed altitude didn't agree with the calculator (azimuth and Ho were spot on). Now, there's not a lot to go wrong here; AP3270 (Lat 53) for the particular GHA (289) and 10 deg Same Name, gave 19 22, 48 and 99 for Hc, d and Z. With a d of 48 and 39 mins of declination, Table five gives a correction of +31 mins, therefore Hc is 19 53. But the calculator gives 19 58 (which would give a much better PL).
I've gone over the sums again and again and just can't see it........
Every now and then I like to practice the art and given that the moon and Jupiter are out at twilight at the moment, I got out my dish of oil and took sights of them both (1 Dec).
I never got round to reducing the sites until this evening and while the moon sight looked good enough, Jupiter was miles out. I used an online site reduction calculator (http://www.celnav.de/sightred.htm) to check my sums, and found that my computed altitude didn't agree with the calculator (azimuth and Ho were spot on). Now, there's not a lot to go wrong here; AP3270 (Lat 53) for the particular GHA (289) and 10 deg Same Name, gave 19 22, 48 and 99 for Hc, d and Z. With a d of 48 and 39 mins of declination, Table five gives a correction of +31 mins, therefore Hc is 19 53. But the calculator gives 19 58 (which would give a much better PL).
I've gone over the sums again and again and just can't see it........