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
    Re: Converting degrees-minutes to degrees and back
    From: Brad Morris
    Date: 2018 Nov 19, 07:35 -0500

    There is no "rule" in today's world.  Most computations are done digitally (electronically).  For that reason alone, computations are done in pure decimal degrees.  The conversions back and forth are done simply for the convenience of the user.

    The one tricky bit is the conversion with negative values, particularly with spreadsheets.  With a little bit of care, however, there is no concern.  Just assure yourself that the conversion is functional.  

    On the otherhand, if you are converting back and forth manually, then in my view, this is very error prone.  More so, in my opinion, than sexagesimal arithmetic of addition and subtraction.  The conversions use multiplication and division.   Perhaps you can do these conversions in your head, but I cannot.


    On Mon, Nov 19, 2018, 12:55 AM Steve E. Bryant <NoReply_Bryant@fer3.com wrote:

    When performing calculations involving degrees and minutes, I much prefer converting the minutes to degrees, proceeding with the additions and subtractions, and then converting the decimal degrees back to minutes.  

    There may be some statistical reason for not doing it that way; or, is the practice perfectly acceptable.   

    There are those professionals who teach navigation that insist upon working only with degrees and minutes, unless it's necessary to use decimal degrees for calculator entry in which case they carry the decimal out to the fifth place.  

    What are the rules, if any, that make the degree/minute conversions unacceptable; and, if there are prohibitions against the practice, is there anything one can do in the process that will statistically justify the conversions?   

    Steve OCBC


    View and reply to this message

    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