Omega
Speedmaster Big S Vintage - Tritium Dial

Omega Speedmaster Professional ST 145.022 — 42 mm — Steel, black “Big S” tritium dial, tachymeter bezel, hand-wound chronograph cal. 861, hesalite crystal, water-resistant 50 m — Pre-owned 1991 — Omega service box

“Wearing a Speedmaster every day is the pleasure of holding a piece of the space race on your wrist, while still looking out at Space from Earth.”

There are watches you wear for what they do, and others you wear for what they represent. The Speedmaster Professional brings both together. In the morning, you pick it up from the bedside table, you feel the controlled weight of the 42 mm steel case, you give the calibre 861 a few turns of the crown. This act of manual winding becomes a ritual: before opening the laptop, having your coffee or heading to the office, you “wake up” your watch just as the engineers used to wake up the capsules before launch.On the wrist, the black tritium “Big S” dial opens up like a miniature instrument panel. The three sub-dials at 3, 6 and 9 o’clock recall workshop chronographs, but for a space-flight enthusiast they are above all echoes of the images of Apollo and the manned missions. The Speedmaster script, with its more generous “S” typical of this period, adds that flavour of detail that connoisseurs spot at first glance.On a normal working day, the Speedmaster behaves like a serious companion: suit, shirt, roll-neck jumper, office jacket – it goes with everything. You glance at the long chronograph seconds hand to time a call, a presentation, a journey. You know that astronauts used the same type of timing for course corrections or re-entry procedures; in everyday life you apply it to more modest realities, but the feeling of handling an instrument born of that history is always there. In the evening, when the screens go dark, the tritium patina reveals itself in softer light. The hesalite crystal throws back slightly blurred reflections around the edge of the dial, the tachymeter bezel takes on shades of grey. There is no need to explain your watch: those who know see immediately what it is, those who don’t simply perceive a well-proportioned steel chronograph, both technical and discreet. For someone passionate about the space race, wearing this ST 145.022 from 1991 every day means keeping a tangible link with that story – an object designed to withstand the constraints of the mission, now adapted to office life, city life, travel.

The Speedmaster was born in 1957 as a sports and racing chronograph, before becoming, over the course of the 1960s, the wrist tool of the Gemini and Apollo programmes. In 1969, during the Apollo 11 mission and those that followed, the Speedmaster Professional took its definitive place in history: it became the “Moonwatch”.The ST 145.022 reference, introduced in the late 1960s, marks an important step in this lineage. It adopted the calibre 861 (replacing the column-wheel 321), a cam-operated movement that is more modern, robust and easier to produce, while preserving the Moonwatch aesthetic: 42 mm asymmetrical case, hesalite crystal, black tachymeter bezel, tritium dial. Examples from the early 1990s, such as this 1991 piece, belong to a pivotal period for today’s enthusiast: old enough to offer real vintage charm (tritium, potential patina, specific typography), recent enough to remain very wearable and reassuring on the wrist day to day. The “Big S” tritium dial is one of the most appreciated traits of this generation. The shape of the Speedmaster signature, with a broader, more open “S”, has become a sought-after detail that immediately singles the watch out in the eyes of a devotee. Combined with a calibre 861 still at the heart of the Moonwatch legend, this configuration makes this 145.022 from 1991 a very coherent Speedmaster for anyone who loves the history of the model without venturing into the most extreme collector references.

This Omega Speedmaster Professional ST 145.022 is built around a 42 mm asymmetrical steel case, with a caseband that protects the crown and chronograph pushers. The case flanks alternate between satin-brushed surfaces and polished edges, in the classic Moonwatch style. The fixed black tachymeter bezel allows the wearer to measure speeds or rates, and remains one of the most iconic visual elements of the model.The matte black “Big S” dial features a tri-compax layout at 3-6-9: small seconds at 9 o’clock, 30-minute totaliser at 3 o’clock, 12-hour totaliser at 6 o’clock. The tritium-painted hour markers and tritium-filled hands contribute to the watch’s vintage identity, with luminous power that is now mainly symbolic but a patina that is often highly prized. The whole offers exemplary legibility, inherited from the need for rapid reading in a professional environment. The domed hesalite plexiglass crystal is another key element of the historical Speedmaster. Originally chosen for its safety in case of impact (it cracks rather than shattering into shards), it now brings a very strong aesthetic signature: soft reflections, slightly distorting edges, a warm rendering of the dial.

Inside beats the hand-wound Omega calibre 861, a direct heir to the movements used on the space missions. With a frequency of 21,600 vibrations per hour, cam-operated architecture and lateral-clutch chronograph, this calibre is renowned for its robustness, stable timekeeping and reliability. The daily manual winding reinforces the bond between watch and wearer, a mechanical dialogue that forms an essential part of the Speedmaster experience. The nominal water resistance of 50 metres is sufficient to cope with everyday life (rain, splashes, hand-washing), provided the usual precautions for a vintage watch are respected and it is not treated as a diver. The watch is offered on a steel Omega bracelet from the period (or an equivalent contemporary version), fully in keeping with the Moonwatch spirit: supple links, comfortable on the wrist, with a technical presence that never becomes ostentatious.

Day to day, this Speedmaster ST 145.022 from 1991 wears like an engineer’s and enthusiast’s watch. In office mode, with a shirt, blazer, chinos or a dark suit, it brings a controlled technical note without ever overpowering the outfit. Its 42 mm diameter remains very current, but the perceived thinness of the case and the absence of a toothed rotating bezel make it less bulky than a modern diver of the same size. At the weekend, it pairs perfectly with jeans, T-shirt, knitwear, a bomber jacket or field jacket. For anyone who loves space history, it is the watch you wear to visit an aerospace museum, to watch a rocket launch on screen, to read about Apollo or the ISS, or simply to remember that our everyday life is built on technical feats of which the Speedmaster remains a symbol.

Its versatility makes it an excellent candidate as the backbone of a collection or as the emblematic piece within a broader line-up. It can be the first Speedmaster for a newcomer, or the “everyday Moonwatch” for an advanced collector looking for an example to wear very regularly, without the reservations that more fragile or rarer references might bring.The example offered is an Omega Speedmaster Professional ST 145.022 “Big S” tritium from 1991, with its black tritium dial, tachymeter bezel and 42 mm steel case. The watch is in very attractive vintage condition consistent with its age. The case retains clear lines and harmonious profiles, the bezel shows patina in line with the period, the black dial and tritium markers display an even ageing, particularly appreciated on this type of piece. The hesalite crystal is in good condition, with a few micro-marks typical of a carefully worn watch, easily polished if one prefers a fresher look.The watch is sold with an Omega service box, which reinforces the coherence of the set and offers a practical, elegant solution for storing and presenting the Speedmaster. Mostra also provides a Mostra luxury case or a suitable presentation solution, so that the watch is ready to join your collection or your wrist straight away.

As with all watches offered by Mostra, this Omega Speedmaster ST 145.022 “Big S” tritium from 1991 has been rigorously inspected by our watchmaking workshop before being offered for sale. Key points have been checked: performance of the calibre 861, chronograph reset, manual winding, time-setting, and the integrity of the case, crystal and bracelet, all in keeping with its vintage character. You can therefore enjoy your Speedmaster with the peace of mind of a supervised purchase. The watch comes with Mostra’s three-year warranty, an exceptional duration on the pre-owned market, especially valuable for a vintage Omega Speedmaster intended for regular wear. This extended warranty reflects our commitment to the careful selection of pieces and the seriousness of our workshop, accustomed to dealing with collectors’ watches and historic chronographs.

Mostra, renowned for its service and customer experience, has been recognised in the specialist press as a pre-owned watch reference. By choosing this Speedmaster 145.022 from Mostra, you are not only acquiring an icon of the space race; you are entering a buying experience designed to last, based on transparency, rigorous selection and personalised support. Our team advises you on model choice, collection coherence, sizing on the wrist and best care practices, with the calm, precise attention that makes all the difference when investing in a heritage piece. Every watch is examined with care before being offered, so that your pleasure in wearing it is both immediate and long-lasting, and our follow-up allows your Speedmaster to live on through the years with a trusted partner at your side. Our reviews are verified and show a five-star rating, reflecting an experience and level of service that meet the expectations of seasoned enthusiasts as well as those choosing their first Moonwatch.