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Transcript
Left to right: Chopard
L.U.C Lunar Big Date
($32,180); Arnold & Son
HM Perpetual Moon
($27,845 in red gold).
STORY BY
B Y J O N AT H O N K E AT S
P H O T OG R A P H Y B Y
JEFF H A R R IS
Stellar Aspirations
A ticking reminder of one’s place in the universe, the astronomical
timepiece makes a lofty addition to your watch collection.
1
ROBB REPORT WATCH COLLECTOR
STELLAR ASPIRATIONS
A
Left to right: Ulysse Nardin Moonstruck
($125,500 in platinum); Ochs und Junior
Moon Phase ($8,000 in titanium).
since the moon orbits Earth every 29-and-a-half days. Or 29 days,
12 hours, 44 minutes, and 2.9 seconds to be precise—and accuracy
is the common cause of astronomy and watchmaking. Horologists
have approached this mechanical challenge by increasing the fineness
of their gearing. On older watches, 59 teeth were cut into a wheel
AMONG THE LESSER-KNOWN
with two full moons—each covered in turn—an arrangement that
facets of the famous rivalry between 1920s-
lost a day every couple of years. By increasing the number of teeth to
era industrialists James Ward Packard and
135, watchmakers have improved accuracy significantly. The large
Henry Graves Jr.—two avid collectors who
classical lunar display on the Arnold & Son HM Perpetual Moon
each ordered successively more complicated
shows the monthly waxing and waning with a lag of just one day
pocket watches from Patek Philippe—is
every 122 years. That performance is matched by the Chopard L.U.C
that both men set their sights on a highly
Lunar Big Date, which presents the lunar cycle on a novel “orbital”
personal complication: They each wanted
display that shows the various moon phases for both the Northern
their nec plus ultra timepiece to feature
and Southern Hemispheres.
celestial time with a star chart depicting
But 122 years is not the mechanical limit. Ludwig Oechslin has
the sky over their respective homes. While
developed an innovative new moon-phase module for the Ochs und
astronomical complications may seem
Junior Moon Phase that deviates by just one day in 3,478.27 years.
arcane to some, enthusiasts recognize (as
Oechslin achieves this feat by using epicyclic gearing, in which a
Packard and Graves once did) that they
train of gears controls the rotation of a disc inside an internally
touch our primal notions of time, which is
toothed hub. The epicyclic gearing and selection of gears within it
why they can still command center stage
allow him to impart an extremely precise ratio of rotation between
in the most complicated timepieces today.
the hour hand and the lunar display: The disc revolves once every
Even before watches and clocks had min-
29.5306122449 days.
ute hands, 17th-century horologists devel-
For Oechslin, this mathematical feat is child’s play. He may be
oped gearwork to display moon phases,
best remembered for the trio of astronomical watches that brought
useful in an agrarian society lacking arti-
Ulysse Nardin’s mechanical watchmaking back to prominence in the
ficial lighting, yet hardly straightforward
1980s and ’90s. Recapitulating the early history of astronomy,
3
ROBB REPORT WATCH COLLECTOR
STELLAR ASPIRATIONS
Left to right: Blancpain Equation of
Time Marchante ($171,300 in red gold);
Audemars Piguet Royal Oak Equation
of Time ($68,700 in stainless steel).
6
ROBB REPORT WATCH COLLECTOR
STELLAR ASPIRATIONS
the Ulysse Nardin Tellurium Johannes Kepler,
However, if you define noon as the time when the sun is highest in
for instance, shows the apparent motion of
the sky—as you would read on a sundial—it wanders by as much as
the sun, the Earth, and the moon from a ter-
16 minutes depending on the time of year. The variation is caused
restrial perspective. The Moonstruck watch
by our planet’s elliptical orbit and the 23-degree tilt of its axis; this
Oechslin conceived with Ulysse Nardin a few
deviation can be mechanically simulated by the annual rotation of
years ago takes up where the Tellurium left
a kidney-shaped or “ellipsoidal” cam that geometrically represents
off. Earth is fixed at the center of the dial,
seasonal time variation. The Audemars Piguet Royal Oak Equation
shown from above the North Pole, with disks
of Time elegantly displays the difference by placing a special blued
for the sun and the moon orbiting around
hand on the same axis as the regular hours and minutes, and orient-
it. Since Oechslin’s mechanism alters the
ing the equation to your local solar zenith (which depends on your
moon phase in tandem with the lunar disk’s
longitude). The cam rotates the blued hand to the exact minute when
rotation, the wearer can see how the moon’s
your sundial would tell you it is noon.
crescent is sculpted by Earth’s shadow. More
profoundly, the watch tracks global tides,
which are caused by the combined gravitational pull of the sun and the moon on the
seas. Of course, the world view shown by
Oechslin’s watch is make-believe, a geocentric
model predating Copernicus. Yet the watch
also helps to explain why that world view
was so persistent, since the information on the
Moonstruck dial consistently corresponds to
B
LANCPAIN’S Equation of Time Marchante takes
another approach to displaying this deviation. A
special secondary minute hand shows sundial time
throughout the day, rather than only indicating solar
noon. Such a running equation is very difficult to
execute mechanically because it requires the hand
to be oriented by the ellipsoidal cam while it is being rotated by the
regular gear train. For that purpose, Blancpain developed a unique
Earth-based observations of the sky above.
set of differential gears. Over the course of the year, the solar hand
Other astronomical functions reveal how
speeds up or slows down to match the path of the sun.
our very concept of time is itself a matter
Sidereal time, the measurement that drove the star charts of rival
of perspective. The complication known as
collectors Graves and Packard, differs from both civil and solar time
equation of time is especially unsettling,
because it derives from the stars rather than the sun. Astronomers
since it openly challenges the position of
define a day as one complete rotation of our planet on its own axis,
the watch’s minute hand by showing the
as measured by the daily crossing of a fixed star infinitely far from
discrepancy between official “civil” time
Earth. Since our standard 24-hour day accounts for both planetary
and the time you’d read on a sundial. The
spin and Earth’s rotation around the sun, the sidereal day is ever
24-hour increments of civil time never vary.
so slightly shorter: 23 hours, 56 minutes, and 4.0905 seconds.
Patek Philippe Sky Moon
Celestial Grand Complication,
Reference 6102 ($329,600).
7
ROBB REPORT WATCH COLLECTOR
STELLAR ASPIRATIONS
Arnold & Son
213.622.1133
www.arnoldandson.com
Audemars Piguet
212.688.6644
www.audemarspiguet.com
Watchmakers seeking to show the night sky
must build a special gear train that runs at
Blancpain
877.520.1735
www.blancpain.com
Chopard
this minutely faster rate.
Sidereal time has been built into the
Jaeger-LeCoultre Rendez-Vous Celestial,
which builds the daily passage of the con-
800.246.7273
stellations in the Northern Hemisphere into
www.us.chopard.com
a romantic women’s timepiece, and the Van
Jaeger-LeCoultre
800.552.8463
www.jaegerlecoultre.com
Cleef & Arpels Midnight in Paris, which
depicts the starry sky specifically over the
French capital.
Patek Philippe has also revisited the
Ochs und Junior
celestial realm with the Sky Moon, a
+41.41.266.02.12
complication whose origins are rooted in
www.ochsundjunior.ch
the watches made for Packard and Graves
Patek Philippe
212.218.1240
www.patek.com
and which is now the hallmark of some
of the brand’s most complex and exclusive
watches. Displaying a broad panoramic
view of the sky, with an overlaid oval
Ulysse Nardin
indicating what can be seen from a given
561.988.8600
latitude and longitude (usually Geneva),
www.ulysse-nardin.com
the Sky Moon is driven by a mechanism
Van Cleef & Arpels
877.826.2533
www.vancleef-arpels.com
that was first released in the Star Caliber
and subsequently miniaturized for the wellknown Sky Moon Tourbillon. The mechanism features an aperture in the deep blue
dial opening to a view of the moon with
Left to right: Van Cleef & Arpels
both the phase and angle accurately shown.
Midnight in Paris ($80,000);
Jaeger-­LeCoultre Rendez-­Vous
Packard and Graves had the privilege of
Celestial ($62,000).
carrying their portions of the night sky
in their pockets. Only now, with the Sky
Moon, can you wear all of it, revolving
with the planet, on your wrist.
10
ROBB REPORT WATCH COLLECTOR