The ActiveEarth Earth Time Instrument is a unique clock design in the ActiveEarth Clock Pack One add-on product that combines many ways to see time on our planet into one, concise "time instrument." Much like an aircraft instrument, this clock makes use of multiple dials and indicators to display as much information as possible while still allowing it to be read at a glance.

The clock has a 24-hour dial with a polar view of the day/night-shaded globe in its center. Cities in the Northern Hemisphere show the North Pole and vice versa. In order to show the earth's rotation correctly, the Earth Time Instrument runs counter-clockwise when displaying the Northern Hemisphere.

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Indicators - There are five indicators that move along with the globe itself: hour, minute, second, daylight saving offset, and the international date line.



Hour, Minute, and Second: The clock displays 24-hour time using pointers into the hour and minute bands. Seconds are ticked off by a moving, red ball.

Daylight saving time offset: The hour indicator is normally placed opposite the selected city. At the same time, the earth is positioned to show its shading properly according to the sun. Because most cities observe daylight saving time during part of the year, there is a difference between the natural "solar time" and the observed local time. The daylight saving offset indicator is placed over the selected city's longitude while the hour indicator is placed to show local time.

International date line: Most of the time (no pun intended) our planet is in two days of the week. Only for the instant that the International date line passes through midnight is there one day of the week. As soon as the line passes through midnight, time zones on either side of the line are in different days of the week. The International date line indicator shows the age of the new day along the 24 hour dial. In the example above, which displays local time in New York City on Monday, Tuesday is already almost seven and half hours old at the International date line.

24 hour dial: One of the handiest things about seeing the globe together with a 24-hour dial is that you can see the approximate times of other places in a glance. For example, while it's almost 3:30 in New York in the image above, it's easy to see that it's about 11AM in California, 9AM in Alaska, and 4AM Tuesday in Japan.

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Northern and Southern Hemispheres - Since the earth rotates West to East, when viewed from the North pole it rotates counter-clockwise and clockwise when viewed from the South pole. To account for this and to show the earth's rotation properly, the ActiveEarth Earth Time Instrument runs backwards or counter-clockwise for cities in the Northern hemisphere. Although this may be odd at first, one quickly gets used to it.



Note that Sydney is not observing daylight saving time at this time of the year. As a result the hour indicator and the daylight saving indicator are aligned; showing that there is no daylight saving time offset. Note also that the two cities are in different days of the week and how that is displayed.