Chac 4+

Warren Anderson

    • 4.0 • 3 Ratings
    • $9.99

Screenshots

Description

Chac is a complete, accurate Maya calendar application.

Chac can find Maya calendar dates based on today’s date, any date, a Long Count, Tzolk’in, Haab’, Calendar Round, Julian day number, distance number, long reckoning , seatings in the cycle of God K and convert between the Julian and Gregorian calendars. Chac can display and find Short Count days.

Chac is also an archaeoastronomy program. It can find the next heliacal or cosmical rising or setting of Venus and the visibility of the current inscription or date. Chac can find the next or last day with a lunar or solar eclipse and will give the time as 24 hour time in time zone -6 and the Julian date of maximum eclipse. Chac can find the the dates of solstices and equinoxes. Chac can find the zenith passage days for a site in the tropics.

Chac calculates the day of the week, Gregorian or Julian date, Julian day number, the Year Bearer, cycle of God K, Long Count, Tzolk’in, Haab’, nine Lords of the Night, lunar deity, moon age and lunation length. Chac can find the heliacal or cosmical risings or settings of Venus. Chac can find solar or lunar eclipses. Chac can find the Solstices and Equinoxes. Chac can find the Zenith passage dates for any site.

You can use a large range of correlation constants, any one of the six possible moon numbers, astronomical or historical dating, any of the four Year Bearer systems and appearance of the new moon or the disappearance of the waning moon. Chac can display a Long Count with head or symbolic glyphs.

Chac draws the results as a complete Maya calendar inscription.

An inscription with its preferences can be saved in Chac’s file format or it can be saved as graphics in tiff, pdf, jpg, png, jp2 or bmp formats. An inscription can also be copied to the clipboard where it will be posted as pdf and tiff. And as inscription data that can be pasted in another inscription window.

What’s New

Version 2.11.7

This is a maintenance update: I fixed one minor bug, edited the Help Book and made small changes to the display of an inscription window.

Ratings and Reviews

4.0 out of 5
3 Ratings

3 Ratings

GPE Correlation is Missing ,

Missing the GPE Correlation

This program is missing the GPE Correlation of Geraldine Ann Patrick Encina, PhD. Please include it.

Developer Response ,

Encina's "correlation" is not a correlation at all. She can't believe that the Maya calendar has no leap years to synchronize it with the tropical year, so contrary to all of the evidence, she has devised an algorithm to do this. You can easily use Chac to verify the fact that her "correlation" only agrees with the astronomical content of the classic inscriptions, codices and the dates used today in Mesoamerica, for a few years around 1473 but accumulates an error of one day every four years because of her reinterpretation of the facts.

You can use her "correlation" by using the converter here: http://damixi.jl.serv.net.mx/test/index.jsp?v=1

Mike Beer ,

Chac

Certainly a useful program for people interested in and working with mesoamerican calendars. Date calculations done by hand are tedious at best, and prone to error. Having a programatic method is a great time saver.
It offers a large number of options for different correlation constants that are probably only of interest to those deeply involved in mesoamerican calendrics or who interpret things written by other authors.
The help files are interesting as a introduction to the topic and contain a set of refernces that are helpful for further study in the topic.
WIth the current media interest in "maya calendars" and the end of the bak'tun it is good to see an honest effort in a sensationalized topic.

App Privacy

The developer, Warren Anderson, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy.

Data Not Collected

The developer does not collect any data from this app.

Privacy practices may vary, for example, based on the features you use or your age. Learn More

Supports

  • Family Sharing

    Up to six family members can use this app with Family Sharing enabled.