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: Lunar tables for month of Brumaire, year IX
    From: Frank Reed
    Date: 2014 Jul 31, 15:45 -0700

    Don wrote: "Wouldn't these tables be for the Paris meridian, at about 2°20' East of Greenwich?"
    And Gary replied: "Oui, mais certainement. "

    Yep! I think you'll find that they are listed for hours of Paris Apparent Time. So when the table lists the Sun-Moon lunar distance for "midi" on the 1st of Brumaire, that's a real "midi", local apparent noon. The lunar distance is correct, up to the limits of their calculational skill, for the instant when the Sun's center is crossing the meridian of the Paris Observatory. My online app will happily provide the lunar distances for hours of Greenwich Apparent Time (as was standard in the early almanacs, instead of GMT), but you'll have to do a short calculation to adjust them to the longitude of Paris.

    -FER

       
    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