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
    or...
       
    Reply
    Re: Stellarium, refraction, HP
    From: Paul Hirose
    Date: 2020 Jan 14, 11:31 -0800

    On 2020-01-12 17:46, Jim Rives wrote:
    > I think this may have been easier if I actually took altitudes for the sun 
    and the moon, but there was no horizon.  I'd love to be able to use 
    Stellarium, or some other tool, to get the altitudes so I can mess with this 
    frequently and actually get fluent it the methods.
    
    If you can run a Windows app, my Lunar program can generate simulated
    altitude observations of either limb (or body center), including
    refraction (corrected for temperature and pressure) and dip if desired.
    For example,
    
    Sun
      28°33.60' computed unrefracted center altitude
        -16.26' unrefracted semidiameter
          1.65' refraction
      28°18.99' apparent lower limb altitude
          0.00' dip
      28°18.99' apparent altitude + dip
    152°22.92' predicted azimuth
    
    I did not turn on the dip feature because the computation was run for my
    location, where the height above sea level would result in an immense
    dip value!
    
    Expected lunar distance is also computed, which is a big convenience if
    you shoot a star lunar since the sextant can be preset. It also predicts
    the position angle (with respect to the zenith) from the Moon to the
    other body. That gives the sextant orientation (about the line of sight
    to the Moon) to bring both bodies into coincidence.
    
    http://sofajpl.com/lunar4_4/index.html
    
    The installer is just a zip file which you extract into any convenient
    folder on your system. Default behavior is that it creates a new folder
    which contains all the application files. Other than that, it does not
    modify your system. If you want a shortcut to the executable on your
    desktop, you must make it by hand.
    
    As installed, the program cannot do anything useful. It needs a JPL
    solar system ephemeris, and one is not included. It's my belief that
    users should learn to do that themselves. You need only decide which
    ephemeris you want, download a couple ASCII files (one is the ephemeris
    itself, the other a "header"), and transform the files into a binary
    ephemeris. A function built into my program does that last step. There
    are instructions on the web site.
    
    The program is really designed for my own needs, but as a courtesy I
    offer it free to the public.
    

       
    Reply
    Browse Files

    Drop Files

    NavList

    What is NavList?

    Join NavList

    Name:
    (please, no nicknames or handles)
    Email:
    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:

    Email Settings

    Posting 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