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
    Sun position and shadow animation
    From: Frank Reed
    Date: 2013 May 16, 16:01 -0700

    Here's a really neat little animation of the Sun's position in the sky and the shadow it casts during the day:
    http://astro.unl.edu/naap/motion3/
    Click on "Paths of the Sun Simulator". This is an Adobe Flash animation, so you won't be able to view it on many handheld devices, especially iPhones and iPads. If you do get it running, click "Start Animation" in the middle, and you can watch the Sun do its thing crossing the sky at any latitude and season. Also it shows the shadow cast by a "gnomon" (the observer's head in this case). You can watch the changing hyperbolic paths of the shadow during the year. The celestial sphere can be rotated around by clicking and dragging. It's a fun toy.

    Thanks to Russell Sampson for pointing this out. He is a professor of physical sciences at Eastern Connecticut State University and was a recent participant in my "Celestial Navigation: 19th Century Methods" class at Mystic Seaport. He has a long-term project to determine the conditions under which Jupiter and other bright stars and planets can be seen in daylight which may also be of interest to some NavList folk. He and Jeremy and I spent an entertaining fifteen minutes in the late afternoon a couple of weeks ago trying to spot Jupiter with sextants. No luck!

    -FER


    ----------------------------------------------------------------
    NavList message boards and member settings: www.fer3.com/NavList
    Members may optionally receive posts by email.
    To cancel email delivery, send a message to NoMail[at]fer3.com
    ----------------------------------------------------------------

       
    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