A. Lange & Söhne Richard Lange Perpetual Calendar Terraluna
One of the most interesting complicated watches to come out of SIHH 2014 is without a doubt the Richard Lange Perpetual Calendar Terraluna from A. Lange & Söhne. It uses a regulator-style dial layout with the addition of a perpetual calendar, a 14-day power reserve, a constant force escapement, and a graphic orbital moonphase complication right on the plate of the movement. This is an absolute beast of a watch and here we have a ton of live photos and all the gritty details for you.
A. Lange & Söhne Richard Lange Perpetual Calendar Terraluna On The Wrist
The first thing you'll notice looking at the Terraluna is just how big it is. At 45.5mm in diameter and 16.5mm thick, the Terraluna is bigger than what most will want to wear on a daily basis. It sits about as well on the wrist as one can hope for at this size, but it's not sliding under any cuffs. The two advantages to the size though are the clarity of the relatively busy dial and the amount of three-dimensonality you can admire in the calibre L096.1 through the sapphire back. The Terraluna is big, but it's big with purpose.
The A. Lange & Söhne Richard Lange Perpetual Calendar Terraluna's Dial
Getting past the size, let's look at this dial. You've got a regulator display for the time, a style that originated in Glashütte in the nineteenth century for scientific clocks. The minutes track is the largest of the three registers, and off to the right you get the hours marked with classic clock-style Roman numerals and to the left you get the seconds register with that signature Lange seconds hand. Sometimes the asymmetry of regulators can be visually distracting, but here is works really well.
Panoramic Big Date
Tucked into each of the timekeeping registers is a display for the perpetual calendar. At the top of the dial is the Lange panoramic big date (inside the minutes register) and the day of the week and month are displayed in windows on the lower left and right respectively.
14-Day Power Reserve Indicator
Visual priority is given to the information you need the most across the whole dial, which is crucial when there is this much going on. Finally you'll see the small "1-4" leap year indicator over by the crown and the curved power reserve indicator at the bottom of the dial.
Orbital Moonphase Indicator On The Calibre L096.1
As if the dial side isn't impressive enough, the real stand-out features of the Terraluna are revealed when you turn the watch over. The calibre L096.1 is just incredible looking, and balances out giving you a look at the mechanics behind the complications and displaying the orbital moonphase indicator.
Closer Look At The Orbital Moonphase Display
Explaining the moonphase without a video can be a little tough (we'll have that for you soon enough), but it's relatively intuitive once it clicks. The balance wheel represents the sun and then there are three discs which represent the earth, sky, and moon. The earth rotates once every 24 hours and you can read the time in each location on the globe on the 24-hour scale around the edge of the movement plate. Simple enough. The sky and moon discs rotate in opposite directions once each lunar month (29 days, 12 hours, 44 minutes, 3 seconds) to show the current phase of the moon through the aperture in the sky disc. You can visualize the current alignment of the earth, moon, and sun easily by looking at the relative positions of the balance, earth disc, and moon display. It will be 1,058 years before this mechanism needs adjusting by just one day. Check out this video to get a better sense of exactly what we mean here:
But there's more to look at on the movement-side of the Terraluna. Of course the movement is crafted from German silver, which gives off that slightly yellow glow, and the balance cock with swan neck regulator is hand engraved like on all A. Lange & Söhne watches. The twin barrels for the 14-day (336 hour!) power reserve are mostly hidden under the moonphase display, but just above the balance wheel you can see the special constant force escapement at work. It pumps out a consistent burst of energy every 10 seconds to compensate for the higher torque that would result from a traditional escapement when the springs are fully wound.
Constant Force Escapement
The Richard Lange Perpetual Calendar Terraluna is not a limited edition, but production will be relatively tight due to the inherent complexity. Both white gold and pink gold cases are available, priced at $216,400 and $215,100 respectively.
For more, visit A. Lange & Söhne online.
