KAIROS 4.0

The program Kairos 4.0 is a general calendar conversion program designed to meet the needs of historians of astronomy, general historians, and anyone who needs to interpret the dates found in historical sources. Historians of astronomy are so often required to convert dates from one calendar to another that they would now naturally look for software designed to make this easy and straightforward.

The name of the program is taken from the Greek word καιρός ,meaning time; the icon is the symbol used in Byzantine texts to represent the conjunction of Sun and Moon.

Kairos designed to run on Windows XP and later Windows systems. The General View shows the screen with some of the available displays.

The program is centred on the list of the principle Calendars. When you select the calendar that drives the program the correct months appear.The time is assigned by typing in the year, etc, but is advanced and retarded at the press of a button. Supplementary windows give further details for  Hebrew, Indian, Persian (including Bactrian) and Chinese calendars, for the positions of Sun, Moon and planets, astrological houses, horoscope , lunar visibility , and the details of  the Latin Easter calculation; the  Mayan calendar. The display takes full advantage of Unicode in the display of the month names

The eclipse display is accessed through the Lunation menu. This leads to a map displaying the path of a total eclipse, which includes also a mouse driven window that shows the appearance of the eclipse at any point of the earth. Here is the eclipse of 2008 Aug 1, total near Beijing.

While some calendar calculations require no more than simple integer-based algorithms, others are dependent on floating point calculations from either modern parameters or from earlier canons. Computations from modern parameters depend on the recently developed semi-analytical solutions VSOP87 for Sun and planets, and on ELP-2000. for the Moon. These are truncated, but without detriment to the precision required in historical research. Medieval parameters are used in the Indian calendars, within a choice of six canons. The Chinese date is computed by the true conjunction calculated from modern parameters.

The Babylonian Calendar appears in two forms, once with the intercalary months as given by Parker and Dubberstein, limited to the years -625 to 76, and again with the regular intercalary months calculated for any year. The dates of visibility are computed from the modern luni-solar program, together with Yallop’s condition for lunar visibility; the window shows the stages before full visibility on the evenings following the conjunction.

A bitmap image of any one of the windows, or of the screen as a whole, may be sent to the printer, or pasted into another window.

The Help file provides succinct accounts of the various calendars.

Please try the Demo version, fully functional, but limited to 30 days.

Once you have tried Kairos you will wonder how you ever managed without it !

The program KairosDemo may be downloaded here:

The cost of Kairos 4.0 is 30 GBP.

Please make your payment by PayPal :

Please note that if you do not have a PayPal account, so that you pay by card, it is necessary to click Return to Merchant after completing the payment. That way you will receive the Registration Number automatically.

However if the PayPal message that you receive on payment does not have Return to Merchant, then wait for an e-mail giving you the registration number. I will have your name and e-mail address from the PayPal receipt which is sent to me.

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