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
    Re: Difference between HO 249 and USNO website
    From: John A
    Date: 2016 May 17, 11:27 -0700

    Hi Gary,

    Thanks for your answer. I guess there is a delay between when a message is posted and it appears on the website, because I figured it out myself before your answer appeared. 

    It all makes sense now, except for the refraction correction. Am I correct in thinking that I can use the A2 Altitude Correction table for "Stars and Planets" to find a rough estimate of the refraction + paralex correction? 

    For example, if I look up the correction for Ha of 21 30', I get -2.4, which is the correct value. 

    It also seems logical that the correction for a point would be the same as for the middle of the Sun. 

    Thanks for your input. 

       
    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