The New Seiko Astron GPS Solar Dual-Time Chronograph Series

A little over two years ago, Seiko introduced the first Astron GPS Solar Dual-Time Chronographs. Following that, the brand gradually launched slightly updated versions featuring new materials and colors. For its 145th anniversary, Seiko revamped its Astron GPS Solar Dual-Time Chronographs. With a new case and caliber, the series gets a proper update. The brand introduces four new models. The Seiko Astron GPS Solar Dual-Time Chronographs HAB001, HAB002, and HAB003 are regular additions to the lineup, and the fourth is the 145th-anniversary limited-edition HAB004. We had a chance to go hands-on with all four.

Fans of the Seiko Astron GPS Solar Dual-Time Chronograph series will immediately notice several changes. The first and most important is a new case design. But if you know the Astron line, you will also recognize similarities with previous releases. Therefore, the new case is a logical step forward. The updated case has a 43.4mm diameter and 12.4mm thickness and is executed in titanium with a super-hard coating across all four models. Its design is characterized by a multifaceted profile featuring a newly introduced two-piece octagonal titanium bezel. The top of the bezel features a brushed finish, while the faceted sides are polished. As a result, the finishing beautifully emphasizes the case shape.

The updated dial design of the Astron GPS Solar Dual-Time Chronographs

Another visual difference compared to the previous generation is the new dial layout. The previous generation featured sub-dials at the 6, 9, and 12 o’clock positions. But the new design has a more balanced look, with sub-dials at 3, 6, and 9 o’clock, making it easier on the eye. This results from the new Seiko caliber 5X63, which replaces the 5X83 that powered the previous generation. In addition to the new layout, the sub-dial order has changed.

First, the main time is displayed centrally, and the additional time zone is displayed in the sub-dial at 6 o’clock. As with previous models, the wearer can swap these time zones by holding down the two pushers for three seconds. As soon as the wearer activates the chronograph, though, the same sub-dial becomes the totalizer for elapsed hours and minutes. There is a major change, though, as the new sub-dial features a 24-hour layout. As a result, the Seiko designers eschewed the AM/PM indicator. Additionally, when in chronograph mode, the totalizer displays elapsed hours and minutes up to a full day.

A different order for the sub-dials

Secondly, the multifunctional sub-dial that displays the day of the week, the chronograph engagement, charging status, and in-flight mode has moved from 9 o’clock to 3 o’clock. Lastly, the sub-dial at 9 o’clock displays the chronograph’s elapsed time to 1/20th of a second. On the previous generation, this sub-dial was located at 12 o’clock. The date window sits between the indexes at 4 and 5 o’clock, just like on the previous model.

All three sub-dials feature concentric graining to contrast nicely with the newly designed base dial. It now features an intricate pattern of interlocking triangles for extra visual impact. On top of that, the base dial serves as the solar panel to charge the watch. What has remained is the flange that holds the minute track, stainless steel hour markers, and a rehaut with the UTC scale. The hour markers have been redesigned to match the dial design nicely and now contain even more LumiBrite. This generous application of lume makes it easier to read the time in the dark.

The new Seiko caliber 5X63

Along with the functions displayed in the sub-dials, the new in-house caliber 5X63 features the same set of features as the previous movement. They include automatic time adjustment when the wearer travels through different time zones. Additionally, if the watch loses signal for automatic time adjustment, it will display that on the dial. Lastly, the movement is accurate to ±15 seconds per month if it doesn’t have a signal.

The new caliber is a significant improvement over the previous one. It rearranges the layout from vertical to horizontal, making it more practical. On top of that, shuffling the displays has made the reading order more logical. So I have to give the Seiko team a huge compliment for updating the caliber and the design to benefit the wearer.

The 145th-anniversary HAB004

Let’s go over the four models and start with the limited-edition HAB004. It features a radiant light silver main dial with a blue seconds track and blue sub-dials. This color combination creates a crisp, modern look that immediately pops.

The watch comes with both a lightweight titanium bracelet and an exclusive silicone strap in white and blue. Switching between the two is now super easy thanks to the new quick-change system. With a push of the button, you can easily remove the strap or bracelet.

Once you have switched between the two, you can press it into place for a secure fit. Huge compliments to Seiko for this because this new system makes swapping between straps and the bracelet super easy. It is one of the most effective systems on the market today.

The new commemorative Seiko Astron HAB004 will be produced in a limited run of 2,000 pieces and will cost €3,000. Included in the price are the lightweight titanium bracelet and the silicone strap. On top of that, the watch will come in special packaging that matches the watch’s white and blue colorway.

Three standard-production references join the lineup

In addition to the commemorative timepiece, Seiko is adding three new models to the regular catalog. The first is the HAB001 in full titanium with a blue-gray dial. The second is the HAB002, which is also in full titanium but with a black dial. Lastly, the HAB003 also has a black dial, but it features a gold-colored inner bezel ring, indexes, and hands. On top of that, this model comes fitted with a black silicone strap.

For me, out of the three standard-production models, the black-dial version with the bracelet would be an easy pick, as it is right in my wheelhouse. But I have to say that the black-dial model with the gold accents has an undeniable charm. Especially in combination with the black silicone strap, it works really well.

The prices for the Astron GPS Solar Dual-Time Chronograph HAB001 and HAB002 in full titanium are €2,800. The HAB003 on the silicone strap is slightly more affordable at €2,700. But if you like the look of the watch with the silicone strap, Seiko also offers white and black silicone straps compatible with all the latest GPS Solar Dual-Time Chronograph models for €210.

Wearing the new Seiko Astron GPS Solar Dual-Time Chronograph series

I had a chance to try out the new Astron GPS Solar Dual-Time Chronograph series, and it pleasantly surprised me. Despite the slightly larger case and the angular, square-ish overall shape, these watches wear very well. From the moment they landed on my wrist, their ergonomics and balanced proportions impressed me. On top of that, the clever mix of finishes adds a distinct level of refinement that had me constantly coming back to these watches. The new titanium bracelet is very nicely made and features a folding clasp with Seiko’s Easy Adjust system, making it simple to size perfectly.

Overall, I was really impressed by the updated Seiko Astron GPS Solar Dual-Time Chronograph series. Initially, when I saw the increased case size alongside the angular case shape, I wasn’t sure whether I would prefer this new series over the previous one in terms of design and comfort. As soon as I put the watches on my wrist, though, my reservations quickly disappeared.

These watches sit really well on the wrist, and thanks to their lightweight titanium construction, they are super easy to wear. Add the new dial design with its updated layout and reshuffled display of the different functions, and this series has improved rather impressively compared to the previous generation. That is definitely a job well done!

All four watches will be available on the Seiko website, in Seiko boutiques, and at select Seiko dealers starting June 2026. Let us know which of these four is your favorite in the comments!