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Clock Gears


Subverting Expectations

In 2017, Omega made a bold move, surprising many who knew the brand for its sports watches and chronographs. They unveiled the Worldtimer, a timepiece that signalled their ambition to venture into more sophisticated horological territory. The debut, timed with the 15th anniversary of the three-hand Seamaster Aqua Terra, was quite a statement. The first Worldtimer released was no ordinary watch. Crafted in solid platinum, it was a limited edition, restricted to just 87 pieces. The standout feature was a sapphire crystal disc at the centre of the dial, meticulously handcrafted with a world map in enamel. It was a unique blend of artistry and precision.

Since that groundbreaking release, the Worldtimer collection has evolved. Now, it boasts seven models, including the classic blue steel version and two newcomers flaunting green ceramic and 18K moonshine gold accents. The most recent addition to the collection is a 43mm Worldtimer housed in a stainless steel case. Its vibrant green rubber strap, accented with grey stitching and a polished steel decorative link, adds a touch of modernity. The sun-brushed green dial, encircled by a polished-brushed green ceramic bezel, presents a unique vision of Earth as seen from the North Pole. Continents, colours, and topography are laser-ablated onto a grade 5 titanium surface.

Around the dial, you'll find representations of global destinations, including Omega's hometown, Bienne, Switzerland. However, London stands out in red, emphasising Greenwich Mean Time (UTC). The city representations are complemented by hands and indexes in 18K Moonshine™ Gold, providing an elegant contrast. Powering this sophisticated timepiece is Omega’s Co-Axial Master Chronometer Calibre 8938, ensuring precision and reliability.

OMEGA Seamaster Aqua Terra Worldtimer GMT in Green and Gold

How to Set the OMEGA GMT Worldtimer

Basic Operation:

  • Normal Position (Wearing Position): The crown is pushed in against the case to maintain water resistance.

  • Occasional Winding: If the watch has not been worn for 60 hours or more, occasional winding is recommended by turning the crown while in Position 1.

Setting Time Zones and Correcting Date:

  • Pull the crown out to position 2. Turning the crown forwards or backward adjusts only the hour hand in 1-hour intervals. This is used for setting different time zones when traveling.

  • Travelling East (e.g., London to Hong Kong): Move the hour hand forward.

  • Travelling West (e.g., London to New York): Move the hour hand backward.

  • The 24-hour hand or disc allows users to quickly check the home time (e.g., London) using the 24-hour scale.

Time Setting:

  • Pull the crown to position 3 for precise time setting. The seconds hand stops. Turning the crown forwards or backward adjusts the 24-hour, hour, minute, and second hands. Synchronise the seconds by pushing the crown back to position 1.

24-Hour 'Worldtimer' Disc: Setting Time and Date for Different Time Zones:

  • Pull the crown to position 3.

  • Turn the crown to move the minutes hand and the 24-hour universal time disc to indicate the UTC (Coordinated Universal Time).

  • Set the 24-hour universal time disc to correspond to different time zones represented by cities or geographic areas on the dial.

  • Push the crown back to position 1 to start the movement.

Adjusting Hour Hand for Date Setting:

  • Pull the crown to position 2.

  • Turn the crown to move the hour hand forward or backward in 1-hour increments to set the date.

  • Ensure that the hour hand is correctly set for the half of the day (morning or evening) to avoid date change errors at midnight.

  • For locations with daylight saving time, add an additional hour when setting the watch during this period.

OMEGA Seamaster Aqua Terra Worldtimer Blue Dial and Steel on a table with maps and shrubbery

Chronometer Certification:

  • A chronometer is a high-precision watch.

  • The movement of a chronometer is individually tested for 15 days.

  • Testing is conducted in 5 positions and at 3 temperatures.

  • The testing is performed by a neutral official body, the Official Swiss Chronometer Testing Institute (COSC).

  • This testing is in accordance with the ISO 3159 (NIHS 95-11) Standard.

  • Each chronometer is unique and is identified by a number engraved on its movement.

COSC: Official Swiss Chronometer Testing Institute:

  • COSC is responsible for certifying the precision and accuracy of watch movements.

NIHS: Swiss Watchmaking Industry Standard:

  • NIHS (Normes de l'industrie Horlogère Suisse) refers to Swiss Watchmaking Industry Standards, and the mentioned NIHS 95-11 standard is specifically related to chronometers.

Master Chronometer OMEGA Certification:

  • In addition to the COSC movement certification, OMEGA Master Chronometer watches undergo additional testing.

  • Watches are individually tested at OMEGA for 10 days before they are delivered to the end customer.

  • Test trials simulate wear of the finished watch.

  • The testing aims to ensure precision, resistance to magnetic fields (1.5 tesla / 15,000 gauss), power reserve, and water resistance.

  • The entire process, including measurement equipment and results, is certified by METAS.

METAS: Federal Institute of Metrology (Switzerland):

  • METAS is the Federal Institute of Metrology in Switzerland.

  • METAS certifies the process, measurement equipment, and results obtained for each Master Chronometer watch.

  • This certification ensures that the watch meets the specified standards for precision, magnetic resistance, power reserve, and water resistance.


Available Now

The OMEGA Seamaster Aqua Terra Worldtimer GMT models are a fascinating addition to the Seamaster collection, blending the elegance of the Aqua Terra line with the functionality of a Worldtimer and GMT complication. These watches are designed to cater to globetrotters and enthusiasts who appreciate both style and practicality. You can check out these stunning preowned watches below:

Close up of OMEGA Seamaster Aqua Terra Worldtimer GMT Green Ceramic and Rubber


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