chronometer, portable timekeeping device of great accuracy, particularly one used for determining longitude at sea.
Is a clock a chronometer?
is that clock is an instrument used to measure or keep track of time; a non-portable timepiece or clock can be a pattern near the heel of a sock or stocking or clock can be a large beetle, especially the european dung beetle (scarabaeus stercorarius ) while chronometer is a device for measuring time, such as a watch or …
What time is kept in chronometer?
The chronometer is normally maintained to UTC time and used as reference clock for other on-board clocks. The board clock will show local time, but it is synchronized with the UTC chronometer at regular intervals.
What is the difference between a chronometer and a watch?
Only watches that have been certified by an official organisation can have the word “chronometer” printed on their dials. A chronometer, in its modern definition, is a watch that has been tested and certified to meet certain precision standards.
What is used to calculate longitude?
Time sight is a general method for determining longitude by celestial observations using a chronometer; these observations are reduced by solving the navigational triangle for meridian angle and require known values for altitude, latitude, and declination; the meridian angle is converted to local hour angle and …
How do we measure longitude?
To measure the longitude you must place the ruler diagonally on the west and east meridians with the ends of the 2 ½ minute ruler touching both meridians. The lines of longitude on your map will be the east and west meridians of your location.
What are chronometer standards?
One of the criteria for « chronometer » certification is the average daily rate on the first 10 days of testing: from -4 sec to +6 sec., or up to 10 seconds per day. A tolerance which, as such, may appear high, but which, in reality, is the result of an extraordinary requirement.
Who made the chronometer?
John Harrison, (born March 1693, Foulby, Yorkshire, Eng. —died March 24, 1776, London), English horologist who invented the first practical marine chronometer, which enabled navigators to compute accurately their longitude at sea.
Why was the chronometer made?
In the middle part of the eighteenth century, John Harrison (1693-1776) solved the longitude problem by constructing a series of chronometers that kept time more accurately than any previous such devices. Running without lubrication, changing temperatures could not cause grease or oil to thicken or thin.
How accurate is a chronometer?
While quartz watches can also be certified as chronometers, the term most often refers to certified mechanical watches that are accurate to within just a few seconds per day (as an example, COSC-certified chronometers must accurate to within -4/+6 seconds a day).
What is another name for chronometer?
In this page you can discover 9 synonyms, antonyms, idiomatic expressions, and related words for chronometer, like: timepiece, clock, hourglass, metronome, timer, watch, wristwatch, chronograph and sextant.
How do chronometer watches work?
Operating a chronograph is actually quite simple: One push-piece starts and stops the process, and the other resets it back to zero. Both push-pieces are usually located on the right side of the case – one at 2 o’clock for stopping and starting and another at 4 o’clock to reset the function.
What is a certified chronometer?
According to COSC, an official certified chronometer is a high precision watch capable of displaying the seconds and housing a movement that has been tested over several days, in different positions, and at different temperatures, by an official, neutral body (COSC).
How is a tachymeter used?
The most common use of a tachymeter is for measuring the approximate speed of a vehicle over a known distance. e.g.) Based on how many seconds it takes a vehicle to travel 1km or 1 mile (the available measuring range is up to 60 seconds), the average speed within the distance can be calculated.