about time ...
Time is a basic component of the measuring system used to sequence events, to compare the durations of events and the intervals between them, and to quantify the motions of objects.
Daylight saving time (DST) is the convention of advancing clocks so that afternoons have more daylight and mornings have less.
In Australia different states have different rules:
- Queensland and Northern Territory does not have DST
- New South Wales, Victoria, Australian Capital Territory (Canberra) and Tasmania observe DST
- Western Australia is in a three year trial period.
In Sydney the Daylight Saving Time starts on the first Sunday in October at 2 AM
and ends on the first Sunday in April at 3 AM
|Australian Time Zones|
|City||State||Standard Time||Daylight Time|
|Currently, where applicable, Daylight Saving Time is On|
: Coordinated Universal Time (UTC) is a high-precision atomic time standard. UTC
has uniform seconds defined by International Atomic Time (TAI
), with leap seconds announced at irregular intervals to compensate for the Earth's slowing rotation and other discrepancies. This allow UTC
to closely track Universal Time (UT), based on the Earth's angular rotation.
The difference between UTC and the old Greenwich Mean Time (GMT
) is less than 0.9 second. In most cases we can consider that UTC
Time zones are expressed as positive or negative offsets from UTC
. Local time is UTC
plus the time zone offset for that location, plus an offset (typically +1) for daylight saving time, if in effect. UTC
on 1 January 1972 as the basis for time reference in different regions.
DST history in NSW...
was introduced nationally during World War I from 1 January 1917 to 25 March 1917 and during World War II for three summers, beginning on 1 January 1942.
was introduced again in NSW
on 31 October 1971 after the Standard Time Act 1971 was voted by the NSW
After a referendum held on 1 May 1976, where 1,882,770 electors were in favor; 868,900 were against and 35,507 votes were informal, DST
was adopted on a permanent basis.
Currently in NSW
the Daylight Saving Time starts on the first Sunday in October and ends at 3 am summer time on the first Sunday in April.
For more information and astronomy enquiries contact the Sydney Observatory
Watson Road, Observatory Hill
The Rocks NSW
PH: (02) 9241 3767
Web Site: Sydney Observatory