NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Sun semidiameter
From: Frank Reed CT
Date: 2007 Apr 17, 19:08 -0700
From: Frank Reed CT
Date: 2007 Apr 17, 19:08 -0700
Herbert Prinz wrote: "The slightly larger value given in the N.A. is also correct. It is apparently based on a value of nominally 16' 01.18" at unit distance. This standard, which was also used in older astronomical almanacs is supposed to account for an irradiation effect. " Could this really be connected with the so-called irradiation correction? It's only a bit more than 1 second of arc larger than the more commonly used value. Surely the irradiation phenomenon was supposed to amount to several tenths of a minute of arc --15 to 20 times larger than this measly arcsecond. -FER PS: I have a suspicion that the message from Herbert Prinz which I am quoting above did not distribute properly to some list members. It was NavList #2570 and you can read it here: http://www.fer3.com/arc/m2.aspx?i=102570&y=200704 if you missed it. --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to NavList@fer3.com To , send email to NavList-@fer3.com -~----------~----~----~----~------~----~------~--~---
