NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Calculate star rise or set time?
From: Gary LaPook
Date: 2015 Nov 19, 10:30 +0000
From: Geoffrey Kolbe <NoReply_GeoffreyKolbe@fer3.com>
To: garylapook@pacbell.net
Sent: Thursday, November 19, 2015 2:20 AM
Subject: [NavList] Re: Calculate star rise or set time?
From: Gary LaPook
Date: 2015 Nov 19, 10:30 +0000
Just search for the term "extinction" in the archive.
gl
From: Geoffrey Kolbe <NoReply_GeoffreyKolbe@fer3.com>
To: garylapook@pacbell.net
Sent: Thursday, November 19, 2015 2:20 AM
Subject: [NavList] Re: Calculate star rise or set time?
On Thu, Nov 19, 2015 at 4:55 AM, Frank Reed <NoReply_FrankReed@fer3.com> wrote:
.....Since you can't see stars right near the horizon in almost all cases, these are reasonable assumptions.
In fact, a simple rule is that a star needs to be a number of degrees equal to its magnitude above the horizon (eg a third magnitude star needs to be three degrees above the horizon) before it is visible. This is simply due to the absorption of light in the atmosphere.
