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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: "A Star To Steer Her BY"????
From: Ken Gebhart
Date: 2005 Jan 31, 21:58 -0600
From: Ken Gebhart
Date: 2005 Jan 31, 21:58 -0600
on 1/31/05 9:20 PM, Joe Shields at jshields@POST-GAZETTE.COM wrote: > As one who has enjoyed practicing celestial navigation and collecting and > reading everything I can find on the subject, the book "A Star To Steer Her > By" has eluded me. I think it was out of print when I first looked for it, > but it is available now, used and new, so I bought a copy. > Now I wish I hadn't. Chapter 2 has several diagrams that are most > upsetting. They show a FLAT earth with a celestial object so close to the > earth surface as to suggest the difference in measured angle with the > horizon (Ho) is due to the fact that the object's rays are approaching at a > different angle instead of the object's parallel rays hitting different > spots on the earth at different angles due to curved surface of the earth > (ignoring horizontal parallax for the moon). While on the surface (no pun > intended) it may not make that much difference (in both cases, the further > one is from directly under the object the less the angle with the horizon > [Ho]), to me it is so essential an understanding that I feel the author does > more harm then good with his book, regardless of the merit of his later > chapters. > > I bought a used 4th printing edition (1994)... somebody please tell me these > diagrams have been fixed in a more current edition. > > -- Joe Shields > Joe, Thank you for the "heads-up". This book has had a good following over a number of years, but we have not carefully analyzed it as you have. it's error is one which I frequently caution beginners to beware of. We will phase it out of our catalog. Ken Gebhart/ Celestaire