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: Spherical Trig
    From: Dan Allen
    Date: 2005 Apr 5, 16:46 -0600

    On Apr 5, 2005, at 4:08 PM, n s gurnell wrote:
    > Re Bill's question about the angles in a spherical triangle.
    > Sixty years ago the exams called "Principles for Second Mates" used to
    > have a
    > question:- "What is Spherical Excess?" I've forgotten the exact answer
    > but
    > someone might know. Old Timer
    The sum of the angles of a spherical triangle is between pi and 3 pi
    radians (180 deg and 540 deg). The amount by which it exceeds 180 deg
    is called the spherical excess and is denoted E. The difference between
    2 pi radians (360 deg) and the sum of the side arc lengths a, b, and c
    is called the spherical defect and is denoted D.
    Girard's formula:
       Spherical Excess = E = A + B + C - pi
         where A,B, and C are angles measured in radians
       Surface Area = E * R^2
         where R is the radius of the sphere

    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