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: Jupiter in daylight and micrometer test
    From: Frank Reed
    Date: 2016 Apr 20, 00:03 -0700

    Peter Monta, you wrote:
    "Would it help to suspend a collimated source in midair near the object of interest? "

    Interesting idea! I have never experimented with a collimated light source, but even an un-collimated marker, if far enough away to be nearly in focus helps tremendously. That's a mouthful to refer to a high tree branch or a roof peak. The catch is getting the angular alignment right. For example, if I know that Jupiter is at altitude 42° and azimuth 141°, I can probably find it in late afternoon in a clear sky if I can place a tree branch right next to that exact location. A workable trick is to find it in a telescope based on true coordinates. Jupiter is almost always visible in a typical backyard telescope, like my old 6" reflector, even in the middle of the day so long as the sky is a nice deep blue. Then switch to binoculars by sighting along the telescope tube. Once you find it binoculars, you can "walk" the planet to a convenient foreground object like a high tree branch. Now aligned with the branch, you lower your binoculars and run a very slow search pattern close to the foreground tree branch. I have found Jupiter in late daylight this way a few times. It sure is easier when the Moon is close by...

    Frank Reed

       
    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