The current version of Mars24 is posted in the Software Tools section of the NASA GISS website. Interested users should revisit the website periodically to check for updates. Alternatively, you may e-mail the author and request to be added to the update announcements mailing list. We also welcome e-mail from users willing to beta test forthcoming versions.
A brief history of significant timekeeping modifications to the code is summarized as follows:
Version 1.0: Released 1998-04-15.
Initial applet release, using timing formulae published in Allison (1997). An outgrowth of an earlier Mars Pathfinder clock applet, this release allowed lookup of the time anywhere on the planet and displayed a simple equirectangular sunclock.
Version 2.0: Released 2000-01-21.
Applet uses updated formulae subsequently published in Allison and McEwen (2000).
Version 3.0: Released 2000-09-15.
Version 3.5: Released 2001-04-11.
Version 4.0: Released 2002-04-25.
Applet uses a revised specification of the inertial location of the Mars prime meridian, replacing that given in Table 4 of AM2000, consistent with the recommendations of Seidelmann et al. (2000, 2002).
Version 4.5: Released 2002-11-07.
First stand-alone application version developed, although only applet version is released to public.
Version 5.0: Released 2003-07-28.
First stand-alone application version released to public.
Version 5.1: Released 2003-10-30.
Mars Exploration Rover mission added.
Conversion between Terrestrial Time (TT) and Universal Coordinated Time (UTC) as given by Equation 27 of AM2000 was modified for greater accuracy with a fourth-order polynomial representation, accurate to within 3 s for 1975-2005.
Calculation of Mars' heliocentric longitude and latitude refined, which in turn allowed for calculation of the light-distance between Earth and Mars to within one second.
Version 5.1.1: Released 2003-12-15.
Calculation of local sunrise and sunset times added.
Version 5.1.3: Released 2004-01-14.
Calculation of sub-Earth point added.
Version 5.2.0: Released 2004-02-20.
Calculation of local earthrise and earthset times added.
Version 5.5: Released 2005-11-30.
Analemma plot added.
Version 6.0: Released 2008-05-18.
Phoenix lander mission time included.
Choice of using p'centric or p'graphic coordinates added.
Version 7.0: Released 2012-06-03.
MSL Curiosity mission time added. Time display window re-designed.
Version 7.1: Released 2015-06-30.