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
    My First Lunar
    From: David Pike
    Date: 2014 Nov 6, 00:46 -0800

     

    Last night I shot my first lunar and proved UTC is out by 8 minutes 49 seconds.  Do you think I ought to warn the Authorities? 

     

    It was a bit of a cheat really.  I was using newly bought Navigator 6.0.1 software, and I knew I was at 53.10N 000.32W, so I used theoretical heights for the Moon and Aldebaran for the corrections.  I also managed to do it all through my lounge window (refraction not corrected for), so I was nice and warm.  On the other hand, it was Nov 5th, Bonfire Night in the UK, and the sky was full of smoke so Aldebaran was barely visible.  Easy to identify though; it was the only star I could see.  It’s possible the far limb of the moon was the wrong one to shoot.  The moon’s almost full at the moment but not quite.

     

    Steady for Astro

     

    Dave

     

    Sextant: Hughes Mate's Three Circle 1941 No: 25410

     

    ++ Lunar calculation -Aldebaran-Moon

     

    + inputs:

     

    date=  5/11/2014

     

    watch time= 21:14:54 GMT

     

    IC= 0.0'  (index correction)

     

    + sextant readings:

     

    hs Aldebaran= 27°28.9'

     

    hs Moon= 41°54.3'

     

    ds Aldebaran-Moon= 40°36.2'    (sextant distance)

     

     

     

    + corrections

     

    obj1: Aldebaran

     

    ha = 27°28.9'

     

     parlx= 0.0'

     

     refr =-1.9'

     

     (c_Aldebaran= 1.9'  refr+parlx)

     

    hc = 27°30.8'

     

     

     

    obj2: Moon

     

    SD=16.2'

     

       + 0.2' (moon disc augmentation)

     

       =16.4'

     

    Lower limb for Moon

     

    ha = 42°10.7'

     

     parlx=43.9'

     

     refr =-1.1'

     

     (c_Moon=-42.9'  refr+parlx)

     

    hc = 42°53.5'

     

     

     

    Far limb for Moon

     

     SD1+SD2=-16.4'

     

    da = 40°19.8'  (apparent dist.- corr. for IC & SDs)

     

     

     

    +refraction and parallax projection factors

     

    A=0.5722 (Aldebaran)

     

    B=-0.1200 (Moon)

     

    Q= 0.3'  (moon quadratic correction)

     

     

     

    + results

     

    dc = 40°26.4'  (cleared distance)

     

     

     

    + lunar time determination

     

    linear interpolation 1 (1 hour interval)

     

    NA dist @ 21:00:00   = 40°30.0'

     

    NA dist @ 22:00:00   = 39°54.7'

     

    Lunar Time = 21:06:05  GMT

     

     

     

    linear interpolation 2 (5 minute interval)

     

    NA dist @ 21:05:00   = 40°27.0'

     

    NA dist @ 21:10:00   = 40°24.1'

     

    Lunar Time = 21:06:05  GMT

     

     

     

    time difference =  0:08:49    (=watch-lunar)

     

    longitude error =  2°12.2'+

     

       
    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