Re: Simple orbit formula?

JRS: In article <4N7me.35126$Ot6.1729151@xxxxxxxxxxxxxxxxxxxxx>, dated
Sat, 28 May 2005 20:11:38, seen in news:sci.astro, Greg Neill
<gneillREM@xxxxxxxxxxxxxxxxxx> posted :
>
>If you're looking for the positions of the actual solar
>system bodies, then you might want to try Paul Schlyter's
>pages:
>
>http://www.stjarnhimlen.se/comp/ppcomp.html

The algorithm in Section 3 of that for converting D M Y is only valid
from 1900-03-01 to 2100-02-29 inclusive, since it implements only the
Leap Year Rule of Caesar, and not those of Pope Gregory. It will be one
day out for every missing Feb 29th between the date in question and the
present day. But it incorporates the Gregorian Shift, so can be used
before the calendar change with a 13-day adjustment.

A full-range version, function PauSch(Y, M, D), can be seen at
<URL:http://www.merlyn.demon.co.uk/js-date1.htm#CtDC> and others in
<URL:http://www.merlyn.demon.co.uk/daycount.htm>.

--
© John Stockton, Surrey, UK. ?@merlyn.demon.co.uk Turnpike v4.00 MIME. ©
Web <URL:http://www.merlyn.demon.co.uk/> - w. FAQish topics, links, acronyms
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Dates - miscdate.htm moredate.htm js-dates.htm pas-time.htm critdate.htm etc.
.