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
    Image of Earth - what is GHA and Dec of the Sun?
    From: Ed Popko
    Date: 2015 Jul 24, 12:57 -0700

    Attached is an image of Earth taken by NASA's Deep Space Climate Observatory satelite on July 6, 2015 and posted today on CNN's Week in Pictures news (7/24/2015).
    What's unusual is the Earth is fully lit. Thus the satelite is very near or on the axis between the centers of the Earth and Sun.

    As we look down that axis at Earth we are also looking directly at the Sun's Ground Point.  So what is the Sun's GHA and Dec at this photo op moment? The date gives us clue about the Sun's Dec but its GHA needs a little noodling.



    File:



       
    Reply
    Browse Files

    Drop Files

    NavList

    What is NavList?

    Get a 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