Post by Admin/YBB on Aug 10, 2022 15:00:20 GMT -6
Daylight Saving Time
US definitions from 01/2007- (definitions were changed several times before).
EST 1st Sun, Nov – 2nd Sun, Mar (late-Fall to early-Winter); UTC-5; S = Standard.
EDT 2nd Sun, Mar – 1st Sun, Nov (late-Winter to early-Fall); UTC-4; D = Daylight.
ET is the current/local Eastern Time that is EST or EDT seasonally.
Note that in the US, the Winter times (EST) are standard/normal. So, if the Summer times are not changed, the sunrise would be quite early and the sunset not so late; other reasons (related to farming, energy use, people shopping, etc) are just rationalizations.
Note that the meaning of only ET changes seasonally. While it won’t make sense to use EDT, say, in Dec (so, 8 AM EST/8 AM ET, but not 9 AM EDT, although technically correct), but EST can be used anytime, and in Summer, it would be correct to use, say, 8 AM EST/9 AM EDT/ 9 AM ET.
In other areas, e.g. Midwest, CT, CST (UTC-6), CDT (UTC-5), etc.
en.wikipedia.org/wiki/Eastern_Time_Zone
greenwichmeantime.com/time-zone/usa/eastern-time/
Edit/Add, 4/15/24. UTC or UT1 is the universal time (1972- ) with offsets in hours:minutes specified for local zones (letters for nautical time offsets may also be indicated); the offsets may change if there is local daylight saving time (e.g. Chicago/Central Time UTC-5/6, CDT/CST); 24-hr clocks start at midnight. The UTC variants are UT0, UT1 (common UTC or GMT), UT2, UT1R, etc. The UTC has replaced the old Greenwich Mean Time GMT (SE London), but GMT is still used in the UK and several countries (some formerly related to the UK) with GMT = UT1.
UTC +/-0 (Z) is for London, Dublin, Lisbon;
UTC +5:30 (E) for India, Sri Lanka;
UTC -6:00 (S) for Chicago, Mexico City.
en.wikipedia.org/wiki/List_of_UTC_offsets
en.wikipedia.org/wiki/Coordinated_Universal_Time
en.wikipedia.org/wiki/Greenwich_Mean_Time
en.wikipedia.org/wiki/Nautical_time
US definitions from 01/2007- (definitions were changed several times before).
EST 1st Sun, Nov – 2nd Sun, Mar (late-Fall to early-Winter); UTC-5; S = Standard.
EDT 2nd Sun, Mar – 1st Sun, Nov (late-Winter to early-Fall); UTC-4; D = Daylight.
ET is the current/local Eastern Time that is EST or EDT seasonally.
Note that in the US, the Winter times (EST) are standard/normal. So, if the Summer times are not changed, the sunrise would be quite early and the sunset not so late; other reasons (related to farming, energy use, people shopping, etc) are just rationalizations.
Note that the meaning of only ET changes seasonally. While it won’t make sense to use EDT, say, in Dec (so, 8 AM EST/8 AM ET, but not 9 AM EDT, although technically correct), but EST can be used anytime, and in Summer, it would be correct to use, say, 8 AM EST/9 AM EDT/ 9 AM ET.
In other areas, e.g. Midwest, CT, CST (UTC-6), CDT (UTC-5), etc.
en.wikipedia.org/wiki/Eastern_Time_Zone
greenwichmeantime.com/time-zone/usa/eastern-time/
Edit/Add, 4/15/24. UTC or UT1 is the universal time (1972- ) with offsets in hours:minutes specified for local zones (letters for nautical time offsets may also be indicated); the offsets may change if there is local daylight saving time (e.g. Chicago/Central Time UTC-5/6, CDT/CST); 24-hr clocks start at midnight. The UTC variants are UT0, UT1 (common UTC or GMT), UT2, UT1R, etc. The UTC has replaced the old Greenwich Mean Time GMT (SE London), but GMT is still used in the UK and several countries (some formerly related to the UK) with GMT = UT1.
UTC +/-0 (Z) is for London, Dublin, Lisbon;
UTC +5:30 (E) for India, Sri Lanka;
UTC -6:00 (S) for Chicago, Mexico City.
en.wikipedia.org/wiki/List_of_UTC_offsets
en.wikipedia.org/wiki/Coordinated_Universal_Time
en.wikipedia.org/wiki/Greenwich_Mean_Time
en.wikipedia.org/wiki/Nautical_time