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In a message dated 3/20/00 9:25:41 PM Pacific Standard Time, KellySt@aol.com 

>  In a message dated 3/20/00 2:42:49 PM, clmanges@worldnet.att.net writes:
>  >> Dead reckoning navigation (see star and go that way) is the method I
>  >intend
>  >> to use and so do not have much use for trigonometric limitations
>  >> or getting lost in space  ;+)>
>  >
>  >You'd really try to pilot a ship over interstellar distances that way??!
>  >You've
>  >got to be kidding.
>  Its trivial.  Aim at the star and boost.  Its not going to move relative 
>  the sky?   Least not in under a few thousand years.  At long as you can 
> range 
>  your distence to know when to start your decel.

Trivial is true as the simpler is the better method.

Taking as example a journey to Alpha Centoria at 4 1/4 light years at a 
constant accelerating 1 g to maintain artificial gravity one need to 
accelerate 1/2 the distance and then turn 180 degrees and decelerate at the 
same rate for the remainder of the distance. (7.68 years round trip earth 
time). The star would be centered in the nose window the first part and then 
centered in the rear view mirror (preventing neck strain) for the 

Though eye fatigue is not a foreseen problem, as I never have tired at 
looking at the stars, I would also rope lash the throttle and directional 
controls to permit sleep, work, rest and other duties with the simplest of 
auto pilot systems devised for sea journies ;=)

The more complicated systems used for navigation today were developed for 
needs as destinations were hidden by curved horizons, mountains, trees, cloud 
cover, darkness, and even unobtainable by encounters with current and wind 

These needs are not present (requiring complex navigational aids) for star 
I take only what I need and like to take.

Taking manual control when in Alpha Centoria's gravity field, ample power 
will be used to check out any orbiting rocks for suitable landing sites.

The reason I think that Hubbell's systems were a poor example as useful, is 
that they often require repairmen from earth not expected on star journeys of 
long distance and time.

An accurate range finder to determine when to decelerate is the current 
problem needing a solution I have yet to find. Measuring distance by star 
brightness is not a good Idea, telescopic resolution of disk diameter is not 
workable for resolution clarity and the trigonometric function tables derived 
from calculus at the angles near zero degrees and 90 degrees are values that 
the calculations differ greatly from measured values over long distances and 
6 place tables are little help. triangleization method  from measuring angles 
to the star from spots opposite in the earth orbit fall in accuracy. I may 
have to steer a zigzag course to get accurate trianangleization data and that 
I do not want to do very often as it would require a path perpendicular to by 
line a travel. 

Doppler shift is so inaccurate as there is no way I know of to determine if 
the doppler shift of acceleration is determined by position location in an 
accelerating universe or a Doppler shift caused by relativistic effects of 
starlight in gravity field.

Does the group have any thought, ideas, methods or machines to solve the 
problem or know of others attempt or solution to answer the question "How far 
is that star?" with any accuracy and given plus or minus values. It would 
seem reasonable to be sure of the distance before starting the journey


>  >>
>  >> Regards,
>  >> Tom
>  >>
>  >> >
>  >> >  Curtis
>  Kelly