A 2-push button, 4-dial, 1/5 second chronograph
THE FIRST WATCH ON THE MOON
The Speedmaster Professional is the watch selected by NASA, without any modifications, for Apollo space missions. It is the first watch on the moon.
The heavy-duty case and sturdy crystal enables the Speedmaster to withstand underwater pressure to a depth of 200 feet.
AS A 1/5 SECOND CHRONOGRAPH
The Speedmaster chronograph measures hours, minutes, seconds and fifths of a second. The 3 hands of the chronograph system - large hand "A" and the small hand of dials "C" and "D" are controlled with the 2 buttons marked "E" and "G". The large second hand "A" is started by pressing button "E" and stopped by pressing button "E" a second time. It will continue to start and stop each time button "E" is pressed. To return the large second hand to zero, press button "E" to stop its motion, then press button "G". Dial "C" totals elapsed minutes. The pointer jumps one division on the dial with each revolution of the large second hand. Dial "D" totals elapsed hours. Its pointer moves half a division on the dial every 30 minutes. The pointers on these dials are controlled by the same buttons that control the large second hand. They start and stop when button "E" is pressed and return to zero when button "G" is pressed. Dial "B" performs the function of an ordinary second hand and is not related to the chronograph mechanism. It remains independent from the working of both push buttons.
AS A TACHO/PRODUCTOMETER
The tachymeter scale "H", on the outer rim can be used to measure speeds of moving objects or production rates. Speed To measure speed per hour of an auto over a known distance of 1 mile, press button "E" when auto begins and press again when distance is covered. The number on scale "H" opposite the position of the large second hand would correspond to miles per hour. Production If a machine produces 100 units in 45 seconds (determined by means of the large second hand) the hourly production can be determined by noting the corresponding number on the tachymeter scale (in this example it would be 80) and multiplying it by 100. The hourly production in this example would be 8000 units.
A Time Capsule by Kesaharu Imai
LINK
- Our Speedmaster Handwinding moon watch collection
- Our Speedmaster Automatic Chronograph collection
- Our Speedmaster Automatic Reduces Chronograph collection
- Our Speedmaster Broad Arrow Automatic Chronograph collection
- Our Speedmaster Ladies Automatic Chronograph With Diamonds collection
- Our X33 Speedmaster Chronograph collection