Welcome to the NavList Message Boards.

NavList:

A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding

Compose Your Message

Message:αβγ
Message:abc
Add Images & Files
    Name or NavList Code:
    Email:
       
    Reply
    Any reliable computation of terrestrial refraction?
    From: Antoine Couëtte
    Date: 2024 Mar 24, 17:16 -0700

    Dear All,

    As this specific topic also requires a dedicated thread, in the end-remark #2 of this most recent post, I indicated that I do not actually know where and how it is possible to compute refraction between 2 points on Earth known by their respective 3D Coordinates on WGS84.

    For example from the Photographer's computed position (WGS84 coordinates assumed to be at 45°08.510701'N 007°52.153984'E 381m) to MonViso (WGS84 coordinates assumed to be at 44°40.059'N 007°05.434'E 3793m) I have computed distance and elevation at 80.776136 km and 2°11.01' .

    For this awesome Moon-MonViso-Superga picture, I "observed and measured" a refraction of 5.66' for MonViso seen at a local height of 2°16.67' from the Photographer's computed position heer-above.

    But I do not know of any practicable method of reliably checking that this 5.66' refraction value is reasonably realistic given what we know of the way light rays are refracted between 2 points at finite distances within the Earth Atmosphere.

    Any NavList Member to bring light on this topic ?

    Thanks in advance.

    Kermit

       
    Reply
    Browse Files

    Drop Files

    NavList

    What is NavList?

    NavList is a community devoted to the preservation and practice of celestial navigation and other methods of traditional position-finding. We're a group of navigators, navigation enthusiasts and hobbyists, mathematicians and physicists, and historians interested in all aspects of navigation but primarily those techniques which are non-electronic.

    To post a message, if you are already signed up as a NavList member, start a new discussion or reply to any posted message and use your posting code (this is a simple low-security password assigned when you join). You may also join by posting. Your first on-topic messsage automatically makes you a member, and a posting code will be assigned and emailed to you for future posts.

    Uniquely, the NavList message boards also permit full interaction entirely by email. You can optionally receive individual posts or daily digests by email, and any member can post messages by email (bypassing the web site) by sending to our posting address which is "NavList@NavList.net". This functionality is similar to a traditional Internet mailing list: post by email, read by email, reply by email. Most members will prefer the web interface here for posting and replying to messages.

    NavList is more than an online community... more about that another day.

    © Copyright notice: please note that the rights to all messages and posts in this discussion group are held by their respective authors. No messages or text or images extracted from messages may be reproduced without the explicit consent of the message author. Email me, Frank Reed, if you have any questions.

    Join / Get NavList ID Code

    Name:
    (please, no nicknames or handles)
    Email:
    Do you want to receive all group messages by email?
    Yes No

    A NavList ID Code guarantees your identity in NavList posts and allows faster posting of messages.

    Retrieve a NavList ID Code

    Enter the email address associated with your NavList messages. Your NavList code will be emailed to you immediately.
    Email:

    Email Settings

    NavList ID Code:

    Custom Index

    Subject:
    Author:
    Start date: (yyyymm dd)
    End date: (yyyymm dd)

    Visit this site
    Visit this site
    Visit this site
    Visit this site
    Visit this site
    Visit this site