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
    Re: Hypothetical Exercise - Abduced By Aliens
    From: Mike Burkes
    Date: 2008 Jun 20, 19:31 -0700

    Hi folks great problem! I also used the small scale "azimuthal
    equidistant proejction" from an atlas, plotted the stars' substellar
    points, and circles  of position but had 3 intersections one was 25d N,
    150.5d W and this one was the basis for the iterations. The real long
    intercepts yielded an initial fix of 23d 43m  N, 157d 25m W enabling
    me to further iterate a fix of 23d 17.5m N, 157d 17.3m W pretty close
    to you folks' results.
    Mike Burkes
    On Jun 15, 10:18�pm, "Greg R."  wrote:
    > [The basis for this hypothetical celnav problem has been discussed (at least 
    in theory) on the list before, so let's try it with a "for real" exercise]
    >
    > After recovering from being unceremoniously dumped on an unknown shore in 
    his/her last adventure (not to mention draining the sailing budget with 
    salvaging the boat and the boatyard repair bills), our intrepid navigator 
    decides that a several-weeks long cruise to somewhere in the distant islands 
    would be just the ticket. Several days into this idyllic voyage a definite 
    feeling of relaxation starts to set in - ah, now this is the life.
    >
    > But of course, it was not to continue... after toasting yet another glorious 
    sunset at sea, our intrepid navigator suddenly finds his/her reverie broken 
    by a group of very bright lights moving rapidly through the sky. After 
    passing close abeam, the lights abruptly change course and hover directly 
    over the boat, illuminating it with what can only be a several-billion 
    candlepower searchlight. To his/her horror, the navigator suddenly finds the 
    entire boat being lifted out of the water and into the open doors of what 
    appears to be some sort of alien spacecraft. Then just as suddenly as they 
    appeared, the armada of alien spacecraft abruptly depart for an uncharted (at 
    least to us) part of the galaxy.
    >
    > Luckily for our intrepid navigator, the aliens are only curious and do 
    him/her no harm. After a couple hours of poking and prodding (and having a 
    good laugh over the primitive Earthling navigation equipment), they realize 
    that the human lifeform is so vastly inferior to their own that nothing 
    further would be gained from holding him/her any longer and they decide to 
    return their captive back to Earth.
    >
    > In an instant (at least in Earth time) they're once again hovering over the 
    navigator's home planet, gently place the boat back in the water, and 
    disappear once again before the navigator has a chance to fully comprehend 
    exactly what just happened.
    >
    > But there's no time to dwell on this latest adventure... like a good 
    navigator s/he realizes that the most pressing problem right now is to figure 
    out where the boat is now located (at least it seems to be on an ocean, which 
    is a good thing...), but notes with some dismay that all of the onboard 
    electronic navigation/computer gear was apparently zapped by being 
    transported to the outer reaches of the galaxy.
    >
    > However, all of the celnav gear (sextant, books, plotting tools, 
    chronometer, etc.) is still intact and onboard, evening twilight is 
    approaching, and with an ironic sense of deja vu the navigator takes these 
    sights:
    >
    > � 05:46:40Z �Vega �Hs = 16�38.8'
    > � 05:52:18Z �Spica �Hs = 54�43.4'
    > � 05:54:26Z �Pollux �Hs = 21�02.6'
    >
    > Height of eye on the boat = 8 feet, index error = 0.0', and assume standard 
    atmospheric conditions (the salvage/repair/refit budget didn't allow for 
    purchasing a new barometer and thermometer). Last known Earth date was June 
    14, 2008 - you can ignore any dilution of time factors (or other effects of 
    trans-space travel).
    >
    > Where are we? And where is the nearest civilization?
    >
    > Discussion item: How would you go about solving this particular navigation problem?
    >
    > --
    > GregR
    --~--~---------~--~----~------------~-------~--~----~
    Navigation List archive: www.fer3.com/arc
    To post, email NavList@fer3.com
    To , email NavList-@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