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
    The Moon is near zenith at 60 N these days
    From: Tony Oz
    Date: 2019 Jan 21, 11:15 -0800

    Hello!
    Spherical trigonometry is tricky or counter-intuitive at times. :)

    I wondered how comes - the Sun is barely above the horizon at LAN (~10°) but the Moon the very same evening mer-passes nearly at zenith? Its' orbit is ~5° to ecliptic - why so big difference in altitudes?

    It took me quite a lot of thinking to comprehend that while the part of ecliptic, where the Sun is now, is currently very deep under the equator - the opposite part of ecliptic is by the same amount above the equator. Plus Moon's ~5° on top of it.
    Hence this small zenith distance for the Moon at its' mer-pass.

    Really, the Moon is still rising here (60°N 30°E) - well on eastward directions - but it is already ~45° high. I must calculate its' altitude at LHA=0°.

    Warm regards,
    Tony
    60°N 30°E

    PS

    Eyebaling an altitude can also be very misleading - an application on a smartphone says the Moon is only ~33° high right now (at ~115° from North).

    :)

       
    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