Where to see the first sunrise of the
new millennium

THERE are many questions that arise in the mind about the millennium. This article is based on a special information leaflet issued by the Royal Observatory Greenwich, as downloaded from the Internet. It covers the most frequently asked questions regarding the start of the new (Christian, Gregorian) millennium and where to see the first sunrise. In summary; the year 2000 will be a leap-year, the new millennium and the new century start at zero hours UTC (commonly known as GMT) on January 1, 2001, and on this basis, the first sunrise of the new millennium will be at places around the world where the sun is rising at that moment.

Why the year 2000 is a leap-year

Leap-years were introduced into the calendar by Julius Caesar to ensure that the months of the year stayed in step with the seasons. This is necessary because the earth makes one rotation of the sun in 365.24219 days, which is clearly not a whole number of days. Adding one extra day every 4 years would exactly correct for a year of 365.25 days but will over correct for a year of 365.24219 days. To make a more exact correction the Gregorian Calendar, introduced in 1582, stated that a century year will only be a leap-year if it was divisible, without remainder, by 400, which is the case for the year 2000. This approximation corresponds to an average year length of 365.2425 days and will amount to a discrepancy of only 1 day after 4000 years. The Gregorian Calendar was adopted in Britain in the year 1752 when September 2, was followed by September 14.

When do the 3rd millennium and the 21st century start?

A millennium is an interval of 1000 years and a century is an interval of 100 years. In the Gregorian Calendar, which we use, there is no year zero and the sequence of years near the start runs as follows;

..., 3BC, 2BC, 1BC, 1AD, 2AD, .…

Because there is no year zero, the first year of the calendar ends at the end of the year named 1 AD. By a similar argument 100 years will have elapsed only at the end of the year 100 AD. Since 2000 AD is the 2,000 th year of the Christian Calendar, two millennia will have elapsed at midnight on December 31, 2000. So the 3rd millennium and the 21st century will begin at the same moment, namely zero hours UTC (commonly known as GMT) on January 1, 2001.

Why the millennium starts at zero hours at Greenwich.

The "International Conference held at Washington for the purpose of fixing a Prime Meridian and a Universal Day’’ in October 1884, resolved to adopt the meridian at Greenwich as the prime meridian for ``all the world’’ and the time and day at the Greenwich meridian as the universal time and day for ``all the world’’. In practice, this time, referred to now more correctly as UTC, is identical to what is widely known as GMT and forms the basis for our claim that the millennium will start at zero hours Greenwich time. The same conference stated that the ``universal day shall not interfere with the use of local or other standard time where desirable.’’ Put simply this means that in Sydney they are not going to wait until 10 next morning before celebrating the New Year.

Where to see the first sunrise of the new mil-lennium.

The purist view

If we accept that the new mil-lennium only starts at zero hours UTC on January1, 2001, then the question is simply where is the sun rising at that instant. The answer is that it is rising along half a great circle running from Eastern Russia, through China out over the Bay of Bengal and down towards the Antarctic Circle. On its way across the Bay of Bengal, it crosses Katchall Island, an island in the Nico-bar group of islands.

The view from Antarctica.

At the South Pole the sun will have risen at the previous Solstice around September 22, 2000, and will not set until about March 22, 2001, the following Solstice. Does this make the South Pole the first place to see the first sunrise of the new millennium on September, 22 2000, or only the last place to see the last sunset of the old millennium?

The US Naval Observatory has pointed out that the sun will set and then rise in Antarctica, at longitude 135 degrees East on the headland between the Dibble Glacier and Victor Bay, at 15:08 UT on January 1, 2000. However, it will only have been below the horizon for less than half an hour that night!

The local time view.

It is common cause that the start of the New Year is celebrated by people around the world according to their own local times and that most people will celebrate the start of the year 2000 not 2001. In practice the difference in times between 2000 and 2001 is negligible.

Will the sun rise at the time stated?

The calculation of the time of sunrise depends on using a model for the way the earth’s atmosphere bends light. For example, when the entire disk is seen to be above the horizon the real sun is still just below the horizon. An average model of the atmosphere is used so that the actual time of sunrise can vary by at least 1 minute, depending on actual conditions.

The last sunset and the first sunrise.

Anyone who accepts that the first sunrise of the new millennium will be seen from Caroline Island has the possibility of flying 1500 miles west to Samoa and seeing the last sunset of the old millennium, 14 hours and 14 minutes later.