Portuguese Sidérale Scafusia

reference 5041

The Portuguese Sidérale Scafusia is the first watch from IWC to feature a patented constant-force tourbillon together with many other complications and individually calculated astronomical displays. Every watch is made on special request and will be unmistakably unique.

Highlights

  • HAND-WOUND
  • SIDEREAL TIME
  • CONSTANT-FORCE TOURBILLON
  • PERPETUAL CALENDAR
  • CUSTOMIZED CELESTIAL CHART
Please contact our concierge for purchase advice

A UNIQUE MASTERPIECE

The design of the dial is in the same characteristic style as that of the entire IWC Portuguese watch family. Apart from standard time (or solar time), it also has a display at “12 o’clock” showing sidereal time (or star time), which is vital to astronomers. The newly developed constant-force tourbillon, which combines a tourbillon with a constant-force mechanism, guarantees a regular and precise rate for a period of at least 48 hours. The 90-hour scale of the power reserve display at “4.30” underscores the enormous power generated by the two barrels.

Variations

Taken together, the choice of materials for the case, the five different colours for the dial, the various colours for the appliqués and straps and the material used for the straps, result in over 200 different design options.

Details

  • Reference 5041
Watch Front
  • Case in platinum, 18-carat red gold or 18-carat white gold
  • Mechanical movement
  • Hand-wound
  • 2 barrels
  • Breguet spring
  • 96-hour power reserve when fully wound
  • Power reserve display at 4.30
  • Constant-force tourbillon and small seconds at 9 o’clock
  • Sidereal time at 12 o’clock
  • Sapphire glass, convex, antireflective on both sides
Watch Back
  • Perpetual calendar with leap year display and absolute day of the year
  • Celestial chart showing horizon, ecliptic and celestial equator
  • Indication for day, night and twilight
  • Display for sunrise and sunset
  • Coordinates of chosen location
  • Sapphire glass
  • Case height 17.5 mm
  • Diameter 46 mm

— The 94900
calibre

Learn More

Watch Viewer

  • 5041  Watch Front
  • 5041  Watch Back

Enlarge

A Glimpse of the Features

  • SOLAR TIMEThe central hour and minute hands show standard time (or mean solar time).

  • Sidérale timeThe subdial at "12 o’clock" shows sidereal time (or star time), a time-keeping system used by astronomers, on a 24-hour display. The time illustrated here is 8.03 a.m. The sidereal time display deviates by just 11.5 seconds per year from real star time.

  • Constant-force tourbillon and seconds handThis completely new combination of tourbillon and constant-force mechanism guarantees a precise and even rate for a period of at least 48 hours. In constant-force mode, the seconds hand jumps once a second. After this, the drive switches to normal mode, which is recognizable from the fact that it advances at the rate of one-fifth of a second.

  • Power reserve displayFully wound, the watch has a 96-hour power reserve.

  • Celestial chartDisplay showing the stars in the night sky as seen from a specific point on the Earth’s surface. It is always calculated individually to the customer's instructions.

  • Horizon and geographical coordinatesThe night sky, currently visible from the geographical position requested by the customer (yellow coordinates), is shown within the yellow ellipse.

  • Perpetual calendarDisplay showing the number of the day of the year on two day counter discs (ordinal date), together with a leap year display. The illustration shows the 188th day in a leap year, in this case 8 July 2012.

  • Solar timeThe red arrow with the dot shows mean solar time on a 24-hour display. The time is read from the outer ring. A solar day is the time taken by the Sun to pass over the same meridian twice.

  • Sidérale timeThe yellow arrow with the star shows sidereal time on a 24-hour display. This is likewise read from the inner ring. A sidereal day is the time taken by a star to cross the same meridian twice.

  • Sunrise and sunsetThese are shown by two red triangle hands on the outer 24-hour ring during standard time. During daylight saving time (DST+1) one must add one hour.

  • Daytime, night-time and twilight displayDaytime, night-time and twilight are indicated by the darkening or lightening of the planisphere.

  • EclipticThe red circle projects the apparent orbit of the Sun in the course of a year on the celestial sphere.

  • Celestial equatorThe dashed grey circle indicates the celestial equator. It is a projection of the Earth’s equator on the celestial sphere and forms a circular plane that separates the northern and southern hemispheres.

TAILORING THE NIGHT SKY

CUSTOMIZED TO THE OWNER’S SPECIFICATIONS

On the rear side of the watch, the night sky disc reveals the full glory of the star-studded heavens. A location chosen by the customer provides the basis of the calculations for the celestial chart and the astronomical displays. Realistically, it is possible to show around 500 to 1,000 stars. The sky disc rotates in a clockwise or anticlockwise direction, depending on whether the chosen geographic location is in the northern or southern hemisphere. The horizon, identifiable as a yellow ellipse, shows the movements of the stars and the section of the sky currently visible in the real night sky above the chosen coordinates. These coordinates indicate the precise location for which the planisphere has been calculated. The red circle projects the apparent orbit of the Sun in the course of a year on the celestial sphere (ecliptic). The dashed grey circle indicates the celestial equator that separates the northern and southern hemispheres. The red arrow with the dot shows solar time on the outer ring of the 24-hour display while the yellow arrow with the star shows sidereal time, likewise on the inner ring. The two red triangle hands at the edge show the current sunrise and sunset times at the chosen location. The perpetual calendar displays the current date as the number of the day of the year (absolute day). The 1st of January, then, is day 1, the 31st of December day 365, or 366 in a leap year.

Twilight, Sunrise and Sunset

—The night sky disc on the back of the
watch changes throughout the day

View How It Works

  • CONTACT IWC TO CUSTOMIZE YOUR PERSONAL PORTUGUESE SIDÉRALE SCAFUSIA

  • Contact IWC

Make It
Your Own

THERE ARE OVER 200 WAYS TO
CUSTOMIZE YOUR MASTERPIECE

As part of its special service, IWC Schaffhausen enables customers to personalize the Portuguese Sidérale Scafusia wristwatch with countless different combinations of features. Taken together, the choice of materials for the case, the five different colours for the dial, the various colours for the appliqués and straps and the material used for the straps, result in over 200 different design options. IWC is only too pleased to honour special requests in the interests of exclusivity.

The case is made of precious metals such as platinum, 18-carat white gold or 18-carat red gold, while the straps are manufactured from the finest alligator leather or equus-hide.

The Portuguese Sidérale Scafusia is personally presented to its new owner in a top-quality watch case. It contains a removable casket, covered in alligator leather, in which the watch can be safely stored. Integrated into the case is an automatic winder, which was developed especially for this watch with IWC’s engineers. It winds the watch independently once a day via the crown. The large celestial chart on the inside of the watch case lid is, like the watch’s own celestial chart, individually calculated.

94900-CALIBRE Movement

THE HAND-WOUND 94900 CALIBRE CONSISTS OF OVER 500 INDIVIDUAL COMPONENTS AND COMBINES THE BASIC MOVEMENT WITH AN ASTRONOMICAL MODULE.

Front view Movement

The imposing constant-force tourbillon gives the viewer a fascinating inside view of the delicately balanced mechanism. The tourbillon’s cage and upper section are made of titanium. The rhodium-plated escape-wheel and nickel-silver stop-wheel bridge are painstakingly hand-chamfered.

Back view Movement

The brushed bottom plate is inlaid with the “Probus Scafusia” stamp – “Good, solid craftsmanship from Schaffhausen” – IWC’s official seal of quality first used in 1903. The retaining plate and power reserve plate are sandblasted and rhodium-plated.

Astronomical Module

The plate for the astronomical module is likewise made of blasted, rhodium-plated nickel silver. It holds all the displays and technical parts such as wheels, levers and bridges that are needed on the rear side.

Comments

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27 comments

  • ttk 8 months, 2 weeks ago

    What a beautiful piece!

  • alastair.weakley 8 months, 2 weeks ago

    Fantastic!

  • ADE 8 months, 2 weeks ago

    What a beauty..... I'm in love! It is sober, fine, original and amazing!

  • david.bliss 8 months, 2 weeks ago

    Brilliant work IWC. I hope to see one in person some day.

  • songxl917 8 months, 2 weeks ago

    Absolutely beautiful, true IWC

  • Q-La 8 months, 2 weeks ago

    Congratulaions for setting a new standard in so many ways.

  • mb 75 8 months, 2 weeks ago

    I'm speechless!

  • Murakami 8 months, 2 weeks ago

    It's one of the most beautiful watches I have ever seen. It's added value to the rest of the collections of IWC. As David said, I hope to see one in person some day.

  • Alec Yin 8 months, 2 weeks ago

    Finally a true innovation! It's truly missed!

  • rubix 8 months, 1 week ago

    There is no better example to indicate how the best there is never an end.Very Compliment !

  • delarey 8 months, 1 week ago

    Perfect.

  • ants1 8 months, 1 week ago

    CONGRATULATIONS IWC! What a MASTERPIECE. You set the pace, the path, but I doubt if any can follow this!!!

  • fandejo 8 months, 1 week ago

    This new model really surprised!

  • Marcel Meier 8 months ago

    Absolutely stunning! I have never seen a watch so fascinating! I would really like to see (and touch, of course) one of these in reality. Although possesing it will never become true for me.

  • higu 7 months, 4 weeks ago

    This is great! Cosmos in a watch!

  • Héctor Coss 7 months, 1 week ago

    Sublime!... Perfect

  • markxvi1967 7 months, 1 week ago

    How much pieces was made? Or is only one piece? What the value of this watch?

  • ABSOLUTELY STUNNING
    (but unfortunately just for a small group of ritch people)
    bas dekkers

  • megagem 6 months, 3 weeks ago

    Mechanical innovation is the key. Coupled with an artistic touch and superior quality - you crate products lasting for generations. Well done and thank you.

  • megagem 6 months, 3 weeks ago

    Mechanical innovation is the key. Coupled with an artistic touch and superior quality - you crate products lasting for generations. Well done and thank you.

  • jbianchi 6 months, 3 weeks ago

    Absolutely beautiful, cosmically complicated

  • mfatihseyhan 6 months, 2 weeks ago

    waww

  • denda 6 months, 2 weeks ago

    What a gorgeous watch! Well done guys!!!

  • Bart7days 6 months, 1 week ago

    Wow!
    Does ik keep time? Can one adjust it self?

  • zacky71 4 months ago

    Absolutely stunning beyond words. A true IWC masterpiece of the century.

  • fyutcha 1 month, 2 weeks ago

    This is Not a Dream O_o

  • kanagaraj_90 4 weeks, 1 day ago

    awesome piece dude...fine, credit to engineer and the designer

Arrow Down 7View all 27 commentsArrow Down

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