Time Zone Master

For Windows XP, Vista, 7 and 8, and its free!

Time Zone Master is a new Windows Clocks program from Relative Data.

A Windows Clock Program Done Right

There are literally hundreds of clock display programs available for Windows. But virtually all of them use Window's own timezone database of UT offsets and daylight saving/summertime rules. But what happens when countries or regions then change to different clock rules? Windows timezone database, and windows clock programs that depend on it, are then wrong and can remain wrong for as long as six months before Microsoft updates their database! Certainly, most Windows clock programs are not something to depend on!

By Using the Olson Zoneinfo tz Database

Instead, Time Zone Master internally uses the comprehensive Olson Zoneinfo tz database, maintained using input from hundreds of corporate contributors worldwide, and used on Linux servers. Whenever any regional clock law change become known and confirmed, the database is quickly updated! Time Zone Master can then automatically download and install these updates within hours, not months! With Time Zone Master, your displayed clocks will always be as accurate as possible; now, and into the future!

It's also a Unique Astronomy and Timezone Research Tool

Time Zone Master adds over 200 countries, and over 45,000 towns and cities to its database, making it easy to select your clocks!

But far more than just a clock display program, Time Zone Master then adds all known historical timezone rules for 300 different world timezone regions going back to at least 1970, and for primary cities in these regions back to before the mid 1800s, making accurate historical time-of-day research possible! In comparison, windows built-in timezone database has NO historical timezone rules data.

Finally, Time Zone Master is also a highly accurate astronomical clock, showing Sunrise/Sunset, Moonrise/Moonset, the times of moon phases, and the start of the seasons, the local Mean Time, Equation of time, Solar Sundial Time, Sidereal Time, and Terrestrial Time for each

of your chosen locations in the past, present or future.

Stay Current with Upcoming Rule Changes

Dozens of regional clock law changes occur every year around the world. Russia recently changed all their clock laws in 2011. Chile, this year, has already changed their laws twice! Egypt has decided to abandon Daylight Saving/'Summer Time' this year. The Falklands have decided to stay on Daylight Saving/'Summer Time' all year round this year. Samoa is considering advancing their clock time by 24 hours, losing a full day off their calendar!

Is your clock program prepared to automatically keep ahead of the numerous clock laws and their rule changes as soon as they become known? Time Zone Master can do it.

Astronomical Accuracy

Time Zone Master can also display various solar and lunar calculations of interest for each location - sunrise, sunset and more. Computations are based on VSOP87 and ELP2000 data, the same data used by astronomers to predict eclipses. Highly accurate astronomical algorithms are used in these computations - comparable to those available from government sources.

A Unique Research Tool

Not only does Time Zone Master allow you to show accurate dates and times now and into the future; you can explore dates and times in the past, showing corresponding clock times using the historical timezone rules that were known to be in effect AT THAT TIME!

  • What time was it in New York when the attack on Pearl Harbor started, using the timezone rules in effect in Hawaii and New York in 1941? When was sunrise on that day?
  • Was daylight/summer time in effect in your birthplace when you where born? Was the Moon up at that time?
  • When did Paris adopt standard time, and what GMT offset was used at that point?
  • After the invasion of Holland in WWII, new clock rules where imposed. What adjustments where made to their clocks at that time, and on which date?
  • In 2010, Egypt adjusted their clocks 4 times. On which dates where the adjustments made?

As a historical research tool, the program is useful for astronomers, stargazers, historians, teachers, genealogists, astrologers, and others.

Large Location Database

The product comes with over 200 countries, and 45,000 locations built in. The data comes from the impressive GeoNames service.

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