the earth rotates from to
about its axis causing day and night on earth. due to this
rotation, the sun in adelaide while perth is still in
the earth rotates in one day. there are different time zones around
the earth. these are generally based on the lines of longitude, known as
measurements of time begin at london with zero degrees longitude. the
international date line is 180 degrees east/west of the prime meridian. each new day begins in
the time zone to the the international date line and works its way around the
world over the next 24 hours.