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: Aldebaran occultation
    From: Alexandre Eremenko
    Date: 2017 Mar 6, 13:27 +0000

    1. Why do you call moonshine "earthshine"?
    2. A 3 sm telescope should have the same effect as my binocular: it will make the star bright enough
    to be visible at the time of occultation.
    I was interested whether people could observe this before the spread of telescopes.
    We have records of occultations since antiquity.
    I am curious how they did this.
    From: NavList@fer3.com [NavList@fer3.com] on behalf of Peter Monta [NoReply_PeterMonta@fer3.com]
    Sent: Sunday, March 5, 2017 11:18 PM
    To: eremenko@math.purdue.edu
    Subject: [NavList] Re: Aldebaran occultation
    Hi Alex,
    Binoculars (or "night glasses" are relatively recent invention, 18 century or so).
    Could people use this method in the earlier times by somehow obscuring (shielding) the Moon?
    I don't know, but that would certainly be a reasonable thing to do.  It's not 
    quite the same issue, but I saw the occultation using a telescope, and one 
    thing that really helped with the earthshine is to keep the bright Moon out 
    of the eyepiece's field of view.  That way the earthshine was actually 
    visible and I could give confident estimates of the time remaining to the 
    rest of the group.
    No way I could do naked eye, but my brother could, all the way to the event.  
    The rest were on binoculars.
    I too would like a convenient, and preferably open-source, tool for really 
    first-class computation of these things.  Apparently the lunar occultation 
    community has one, but it's Windows, so I didn't quite have time to get it up 
    and running.  Also it's not clear exactly how it does the lunar topography, 
    but the ephemeris stuff sounded okay (DExxx).
    View and reply to this 

    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