Nebula 38 Steel | © Arnold & Son
© Arnold & Son

Nebula 38: steel structural elegance from Arnold & Son

Following the launch of a red-gold version, the Nebula 38 is now available in steel. The house’s iconic watch is now entering new territory where ultra-technical watchmaking is encased in an understated exterior, with a diameter rarely seen in this category and exemplary slimness.

The name ‘Nebula’ was chosen because the sculptural movement driving this timepiece evokes an inverted star that has exploded in an ideal orderly fashion. All of its bridges converge from the outside of the dial towards the centre, like perfectly symmetrical rays. In terms of complications, the Nebula 38 belongs to the family of three-handed watches indicating the hours, minutes and off-centred small seconds. Lastly, in terms of complexity, this timepiece constitutes one of the most graphically striking, high-impact and original skeleton watches.


When it comes to the dial, it is reduced to a black lacquered flange, while the calibre mesmerises the eye with its arrangement, layers and curves. Here, the A&S5101 calibre is the dominant orator, speaking in the style of John Arnold.

Furthermore, the structure of the A&S5101 calibre is based on carefully considered symmetry. Seven bridges span the four axes that cross the Nebula 38, creating a sense of visual balance. Meanwhile, the proportions are communicated by the dimensions of the steel case; a diameter of 38 mm for a thickness of 8.91 mm. A domed sapphire crystal covers the dial side and a flat sapphire crystal on the case back.

On the dial side, the Nebula 38 reveals a double barrel bridge, crown bridge, balance bridge, geartrain bridges. The small-seconds function at 7 o’clock, for example, is twinned with the balance. While technically different, these two blocks adopt similar shapes to perfect the movement’s sense of equilibrium. The harmony is plain to see, as all the bridges, plates and solid components are open-worked.

Order and beauty

Nebula 38 Steel | © Arnold & Son
Nebula 38 Steel | © Arnold & Son

To maintain symmetry, Arnold & Son moved the winding mechanism linked to the crown stem to the case back. In addition, the Nebula 38 was designed with practicality in mind, as it boasts a 90-hour power reserve. This is a rarity for skeleton models.

To ward off any risk of illegibility, the bridges are of the same height on the dial side; however, on the case-back side, a large sapphire crystal reveals a mainplate that has been open-worked to the extreme. Its design features several criss-crossing arcs, with intersecting circles and ellipses that are reminiscent of a Gothic cathedral’s vault.

In conclusion Nebula 38 Steel is ergonomic yet technical, aesthetic yet legible, and expressive yet slim. It is, indeed, a unique timepiece.

Technical information:

Functions: hours, minutes, small seconds
Calibre: A&S5101, hand-wound mechanical
Jewels: 24
Diameter: 31.50 mm
Thickness: 4.04 mm
Power reserve: 90 hours
Case material: stainless steel
Diameter/thickness: 38 mm/ 8.91 mm
Crystal: domed sapphire with an anti-reflective coating on both sides
Case back: sapphire crystal
Water-resistance: 30 metres

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