Portal:Time
WELCOME TO THE TIME PORTAL
| Time | Portals & WikiProjects | Categories & Wikimedia | Things you can do |
Time Time is a fundamental component of measuring systems and has long been a major subject of art, philosophy, and science. In physics and other sciences, time is considered a fundamental quantity; part of the basic structure of the universe, a dimension in which events occur in sequence. The unit of time in the International System of Units (SI) is the second...
Time Help
More Time & Date Templates: Time TopicsTime (book) touches upon nearly every topic in some way. Some of the most relevant are below:
Selected articleA chronometer watch is a watch tested and certified to meet certain precision standards. In Switzerland, only timepieces certified by the COSC may use the word 'Chronometer' on them. However, numerous prominent Swiss watch manufacturers do not submit their movements for COSC certification, although such movements would probably easily qualify as chronometers under the COSC certification rules. The term chronometer is also used to describe a marine chronometer used for celestial navigation. The marine chronometer was invented by John Harrison in 1730. This was the first iteration of a series of chronometers which enabled accurate marine navigation. For the next 250 years, an accurate chronometer was essential to any kind of marine or air navigation until the implementation of global satellite navigation at the end of the 20th century. The marine chronometer is no longer used for navigation. Selected pictureSelected biographyDid you know......that the second was known as a "second minute", the second small division of an hour. ...that the second is defined as the duration of 9,192,631,770 oscillations between the two hyperfine levels of the ground state in the Cesium-133 atom. ...that the smallest unit of time that could ever be measured is the Planck time (~ 5.4 × 10−44 seconds). ..that despite Herodotus's claim that the sundial was invented in Babylon, the oldest known example is from Egypt? ... that merkhets were Ancient Egyptian timekeeping devices that tracked the movement of certain stars over the meridian in order to ascertain the time during the night, when sundials could not function? Things you can do - Carpe diem because Tempus fugit
Related portalsWikiProjectsDescendant WikiProjects Related WikiProjects Associated WikimediaCategoriesQuotes
|
