NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Anyone own a copy of the StarPilot software?
From: Pierre Boucher
Date: 2006 Jul 4, 22:53 -0500
Frank Reed a écrit :
> For the position of alpha Centauri on July 1, 1806 as given in the
> StarPilot software, Pierre wrote:
> "SHA 143d 42.7'
> Dec -60d 01.8' "
>
> Merci!
> And just to clarify, you took these numbers from the calculator version
> of the StarPilot software, yes?
The above are from th PC software (ver 3.06).
The Calculator version#1.55 (nov 2001) TI86 shows:
SHA 143d 41.2'
Dec -59d 59.9'
...!!!
Pierre
I have seen the same numbers in the PC
> version, and I want to confirm that the calculator version has the same
> problem.
>
> A friend of mine has been experimenting with the demo of the PC version
> of StarPilot, and I asked her to write down a few test values of SHA
> for some objects for the date July 1, 1806. The positions of the Sun,
> Moon, and planets are solid within the error limits defined for the
> product, no more than about 1/4 of a minute of arc error in position.
> The positions of the stars are clearly wrong over such long periods of
> time. The SHA of Pollux is off by 2.2', the SHA of Altair is off by
> -1.6', Arcturus is out by 3.5', and alpha Centauri is wrong by a
> whopping 21.9'. By contrast, distant stars with low proper motions have
> positions which are wrong by only a tenth of a minute or arc or so:
> Antares 0.1', Canopus -0.1', Rigel 0.0'.
>
> These positional errors are directly proportional to the distance in
> time from the year 2000, so I want to re-iterate that they are NOT
> significant for modern navigation, only for analysis of historical
> sights.
>
> -FER
>
>
> >
>
>
--
************************************************************************
Pierre Boucher N
formation en navigation de plaisance
Ste-Therese (Quebec) Canada
la "VOILE" ... le reste n'est que du vent...
"Sail, Sail !"... the rest is only wind...
EMAIL: pboucher@lavoile.com
http://www.lavoile.com
************************************************************************
--~--~---------~--~----~------------~-------~--~----~
To post to this group, send email to NavList@fer3.com
To , send email to NavList-@fer3.com
-~----------~----~----~----~------~----~------~--~---
From: Pierre Boucher
Date: 2006 Jul 4, 22:53 -0500
Frank Reed a écrit :
> For the position of alpha Centauri on July 1, 1806 as given in the
> StarPilot software, Pierre wrote:
> "SHA 143d 42.7'
> Dec -60d 01.8' "
>
> Merci!
> And just to clarify, you took these numbers from the calculator version
> of the StarPilot software, yes?
The above are from th PC software (ver 3.06).
The Calculator version#1.55 (nov 2001) TI86 shows:
SHA 143d 41.2'
Dec -59d 59.9'
...!!!
Pierre
I have seen the same numbers in the PC
> version, and I want to confirm that the calculator version has the same
> problem.
>
> A friend of mine has been experimenting with the demo of the PC version
> of StarPilot, and I asked her to write down a few test values of SHA
> for some objects for the date July 1, 1806. The positions of the Sun,
> Moon, and planets are solid within the error limits defined for the
> product, no more than about 1/4 of a minute of arc error in position.
> The positions of the stars are clearly wrong over such long periods of
> time. The SHA of Pollux is off by 2.2', the SHA of Altair is off by
> -1.6', Arcturus is out by 3.5', and alpha Centauri is wrong by a
> whopping 21.9'. By contrast, distant stars with low proper motions have
> positions which are wrong by only a tenth of a minute or arc or so:
> Antares 0.1', Canopus -0.1', Rigel 0.0'.
>
> These positional errors are directly proportional to the distance in
> time from the year 2000, so I want to re-iterate that they are NOT
> significant for modern navigation, only for analysis of historical
> sights.
>
> -FER
>
>
> >
>
>
--
************************************************************************
Pierre Boucher N
formation en navigation de plaisance
Ste-Therese (Quebec) Canada
la "VOILE" ... le reste n'est que du vent...
"Sail, Sail !"... the rest is only wind...
EMAIL: pboucher@lavoile.com
http://www.lavoile.com
************************************************************************
--~--~---------~--~----~------------~-------~--~----~
To post to this group, send email to NavList@fer3.com
To , send email to NavList-@fer3.com
-~----------~----~----~----~------~----~------~--~---
