Software Bisque Knowledge Base Article – 223

PRE-4000 B.C. SOLAR SYSTEM POSITIONS INCORRECT

ISSUE

When using TheSky to display positions of Solar System objects (e.g. planets), or star positions (relative to horizon), results are incorrect for ancient (pre-4000 B.C.) dates.

RESOLUTION

Early versions of TheSky v4.00 for Windows had a date limit of 4000 B.C. to A.D. 10000. By the release of v4.00.105, the date entry limit had been extended backward to 4712 B.C., however the computational algorithms still had the 4000 B.C. limit.

Because of this inconsistency, setting the date and time (Data, Site Information, Date & Time) to a year less than -4000 always gives the result for January 1 of 4000 B.C. (thus, changing the date within this range will not alter the Sky Display). When performing a Time Skip across this limit, results prior to -4001 will be treated as the year -4001.

This problem was corrected, and the date limit further extended to 4713 B.C. in TheSky v4.00.200. The user should obtain this, or a later version.

APPLIES TO

Time Skip

KEYWORDS

SBKB

This article was formerly published under the identifier Q447KB in Software Bisque’s prior knowledge base.

Last Reviewed: 11/24/2004