Welcome to the NavList Message Boards.


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

Compose Your Message

Add Images & Files
    Astronomical Refraction: Computational Method for All Zenith Angles
    From: Frank Reed CT
    Date: 2005 Aug 17, 00:17 EDT

    Marcel asked:
    "Does anyone of you know where  to obtain a newer program in source code and
    with a description of what it  does?"
    No source code, but there's an excellent short article by  Auer and Standish
    on this topic including sample calculations for various  temperatures and
    pressures and even for negative altitudes as seen from 15,000  meters observer
    height (just the thing that got you started on this!) in the  Astronomical
    Journal for May, 2000 [AJ,119:2472-2474,2000 May]. This is the  calculational
    approach recommended in the 'Explanatory Supplement to the  Astronomical Almanac',
    so it doesn't get much better. Checking against the  tables in the Nautical
    Almanac, the refraction values generated by this  algorithm are an exact match
    except for differences of a couple of tenths of a  minute of arc very close to
    the horizon.
    You can get the article in .pdf  format from ADS  here:
    http://adsabs.harvard.edu/advanced_fulltext_service.html .
    But  to save searching and for those list members who want the article but
    don't get  along well with pdf files, I've made a link to .gif copies of the
    article's  three pages here:
    http://www.HistoricalAtlas.com/lunars/ref.html  .
    42.0N 87.7W, or 41.4N 72.1W.

    Browse Files

    Drop Files


    What is NavList?

    Join NavList

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

    You can also join by posting. Your first on-topic post automatically makes you a member.

    Posting Code

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

    Email Settings

    Posting Code:

    Custom Index

    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