SEIKO ASTRON SSH187J1 SPIRAL GALAXY LIMITED EDITION GPS SOLAR CHRONOGRAPH MEN WATCH

Seiko Astron SSH187J1 — Spiral Galaxy Limited Edition GPS Solar Chronograph

The Seiko Astron SSH187J1 is one of only 1,500 pieces produced worldwide — a limited edition GPS solar chronograph themed "Solidity," created to symbolise Seiko's innovative spirit and the forward momentum of its watchmaking since 1881. Part of a solar system-inspired series, the SSH187J1 brings together the most technically ambitious dial in the Astron collection with the most capable movement Seiko has ever fitted to it: the in-house 5X83 GPS solar calibre, featuring a 1/20th of a second chronograph function alongside GPS satellite time zone adjustment and dual time capability.

The spiral galaxy dial in dark turquoise blue is a genuine engineering achievement — particularly difficult to create on a functioning solar cell while maintaining charge efficiency. The glittered effect across the surface depicts stars in deep space, while the circular whirling pattern gives the dial a sense of motion and depth that photographs cannot fully capture. The all-black 43.3mm super hard coated titanium case with ceramic bezel and dual-curved sapphire crystal frames it with a gravity and presence entirely befitting a piece of this significance. With mirror-effect centre bracelet links and a micro-adjustable clasp, the execution extends from dial to wrist without compromise.

Key Features

• Seiko 5X83 GPS solar movement — pinpoints your exact time zone by receiving signals from 4 or more GPS satellites
• Accuracy: ±1 second every 100,000 years with daily automatic GPS time adjustment — the most accurate wristwatch technology available
• 1/20th of a second chronograph — measures elapsed time up to 12 hours with exceptional precision
• Dual time capability — bottom subdial adjustable to a second time zone; main hands manually adjustable to different time zones
• Perpetual calendar — automatically adjusts for short months and leap years until February 2100
• Day-date display — full calendar functionality built in
• Approx. 6-month power reserve at full charge; approx. 2-year power save reserve — exceptional solar efficiency
• Power reserve indicator — monitor remaining charge at a glance
• Spiral galaxy turquoise blue dial with glittered star effect — technically complex solar cell dial, unique in the Astron collection
• Subdial at 12 o'clock for chronograph; subdial at 9 o'clock for setting modes; subdial at 6 o'clock for dual time — purposeful, readable layout
• All-black super hard coated titanium case at 43.3mm — lightweight, strong, and exceptionally durable
• Ceramic bezel — scratch-resistant and precisely finished
• Dual-curved sapphire crystal with super clear coating — premium scratch resistance and superior optical clarity
• Black titanium bracelet with mirror-effect centre links — lightweight and refined
• Micro-adjustable clasp — personalised fit with incremental adjustment
• AM/PM indicator — clear 12-hour cycle reference
• Lumibrite on hands and markers — superior low-light legibility
• 100M water resistance — swim-ready and built for active lifestyles
• Limited edition — only 1,500 pieces produced worldwide

Why You'll Love It

The SSH187J1 is the most fully specified of the Spiral Galaxy limited editions — combining the visual drama of the turquoise galaxy dial with the technical depth of the 5X83 chronograph calibre. The 1/20th of a second chronograph adds genuine sporting utility to what is already an extraordinary timepiece, the dual time feature makes it as practical for travel as it is impressive at rest, and GPS accuracy to ±1 second every 100,000 years means the technology is as uncompromising as the design. The spiral galaxy dial remains the centrepiece — an engineering achievement on a functioning solar cell that gives the watch a depth and movement in real life that no image can replicate. The glittered star effect changes character in different light, the all-black titanium construction keeps it featherlight despite the 43.3mm presence, and the perpetual calendar running to 2100 means it will outlast every one of its 1,500 owners. A defining piece in the modern Astron story.

SSH187J1 vs SSJ039J1 — Which Spiral Galaxy Should You Choose?

Both models share the Spiral Galaxy dial concept in dark turquoise blue with glittered star effect, all-black titanium construction, ceramic bezel, and 1,500-piece worldwide limitation. The key differences are movement and size. The SSJ039J1 uses the 3X62 GPS solar calibre — a 3-hand calendar movement in a slimmer 41.2mm × 12mm case — for those who prefer a cleaner dial and a more compact wearing experience. The SSH187J1 uses the 5X83 GPS solar calibre — adding a 1/20th of a second chronograph, dual time, and day-date display in a larger 43.3mm × 13.4mm case. Both share GPS accuracy to ±1 second every 100,000 years. The choice comes down to whether you want the purest expression of the Spiral Galaxy dial, or the most capable specification it has ever been paired with.

The Seiko Astron Story

Seiko Astron is the world's first GPS solar watch — powered by light and automatically adjusted to your exact time zone through satellite technology. Since the first Astron was introduced in 1969 as the world's first quartz watch, Seiko has continuously pushed the boundaries of what a wristwatch can do. The GPS Solar Astron, launched in 2012, represented a new frontier — a watch that never needs setting, never runs out of power in normal use, and is accurate to a standard no mechanical or conventional quartz watch can match. The SSH187J1 Spiral Galaxy represents the meeting point of that technical ambition and Seiko's most ambitious dial artistry — in limited edition form that will only become more significant with time.

Backed by Seiko's official warranty. Authentic Seiko Astron limited edition watch, sold by authorised retailer City Chain Singapore.

Also available as the 3-hand GPS solar — shop the SSJ039J1 and the 145th Anniversary Limited Edition — shop the SSH186J1. Explore the full Seiko Astron Collection or browse all Seiko watches at City Chain Singapore.