Guide Timezones: Difference between revisions
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===The Issue=== |
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usually we use local time, which is correlated to the sun's position. but what to do, if one person is located in UK and another person is located in Austrialia, how can they arrange a meeting? |
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Timezones have been implemente to simplify time related problems as the clock shows time related to the/your geographical location and the position of the sun. If is noon (12:00) in Greenwich, the clock may show different time although is exact same time on a local clock, depending on position. |
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===The Soution=== |
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To reflecting this issue, timezones were created. these zones change offset every 15°, if east to Greenwich, they add 1 hour, if east they substract 1 hour. |
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In the past '''[[:en:Greenwich_Mean_Time GMT|GMT]]''' was the clocktime, which never changed. Nowadays '''[[:en:Coordinated_Universal_Time|UTC]]''' is used, which is (the more the less) an equivalent/synonym for GMT, '''ZULU''' is another synonym |
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so if you travel around the world, you need to change your clock's time every 15° longitude. Timezones reflect this. |
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Every 15°, if east to Greenwich, add 1 hour, if west substract 1 hour. |
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The local time is calculated as follows: '''GMT''' + Timezone Offset = '''LST''' ('''l'''ocal '''s'''tandard'''t'''ime) |
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to reflecting the summertime, the offset is added to the '''LST''' which then gives the '''LCT''' ('''l'''ocal '''c'''ivil'''t'''ime) and voilá this is the time, your clock shows. |
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To actually setting your clock to correct time, you need to know '''GMT/UTC''' time and add the timezone offset to it. this gives you your local standard time ('''LST''') (GMT + timezone offset = LST) |
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For saving energy summertime was invented in [https://en.wikipedia.org/wiki/World_War_I|World War I]. so this offset needs to be added to the LST to giving you the time which then is called local civil time ('''LCT''') (LST + summertime offset = LCT) |
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Latest revision as of 05:10, 19 August 2024
The Issue
usually we use local time, which is correlated to the sun's position. but what to do, if one person is located in UK and another person is located in Austrialia, how can they arrange a meeting?
The Soution
In the past GMT was the clocktime, which never changed. Nowadays UTC is used, which is (the more the less) an equivalent/synonym for GMT, ZULU is another synonym
so if you travel around the world, you need to change your clock's time every 15° longitude. Timezones reflect this.
Every 15°, if east to Greenwich, add 1 hour, if west substract 1 hour.
To actually setting your clock to correct time, you need to know GMT/UTC time and add the timezone offset to it. this gives you your local standard time (LST) (GMT + timezone offset = LST)
For saving energy summertime was invented in War I. so this offset needs to be added to the LST to giving you the time which then is called local civil time (LCT) (LST + summertime offset = LCT)