Blue Moon - The Blue Moon of 2020

Our Blue Moon Calculator says that in 2020, there is a Blue Moon in October. Is that true in all parts of the world? After all, previous Blue Moons have fallen on different days in different parts of the world.

Let's start with the basic astronomical facts. The Full Moons for October and November 2020 are as follows:

1 October 2020	at	21:05 UTC
31 October 2020	at	14:49 UTC
30 November 2020	at	09:29 UTC

These dates and times have been calculated rigorously using the same methods as those employed by the United States Naval Observatory and by Her Majesty's Nautical Almanac Office. They are given in Coordinated Universal Time (UTC) which is the standard time zone used by astronomers worldwide. It is effectively the same as Greenwich Mean Time (GMT).

Here are those three Full Moons again, but with the dates and times adjusted for several major time zones around the world. For each time zone, the two Full Moons which fall in the same calendar month are highlighted.

City	Standard Time Zone	Full Moon 1	Full Moon 2	Full Moon 3
Places East of Greenwich
Auckland	UTC + 12 hours	Oct 2 10:05¹	Nov 1 03:49¹	Nov 30 22:29¹
Sydney	UTC + 10 hours	Oct 2 07:05	Nov 1 01:49¹	Nov 30 20:29¹
Brisbane	UTC + 10 hours	Oct 2 07:05	Nov 1 00:49	Nov 30 19:29
Adelaide	UTC + 9 hours 30 minutes	Oct 2 06:35	Nov 1 01:19¹	Nov 30 19:59¹
Tokyo	UTC + 9 hours	Oct 2 06:05	Oct 31 23:49	Nov 30 18:29
Perth	UTC + 8 hours	Oct 2 05:05	Oct 31 22:49	Nov 30 17:29
Kolkata	UTC + 5 hours 30 minutes	Oct 2 02:35	Oct 31 20:19	Nov 30 14:59
Karachi	UTC + 5 hours	Oct 2 02:05	Oct 31 19:49	Nov 30 14:29
Moscow	UTC + 3 hours	Oct 2 00:05	Oct 31 17:49	Nov 30 12:29
Johannesburg	UTC + 2 hours	Oct 1 23:05	Oct 31 16:49	Nov 30 11:29
Paris	UTC + 1 hours	Oct 1 23:05¹	Oct 31 15:49	Nov 30 10:29
The Greenwich Meridian
London	UTC	Oct 1 22:05¹	Oct 31 14:49	Nov 30 09:29
Places West of Greenwich
Sao_Paulo	UTC - 3 hours	Oct 1 18:05	Oct 31 12:49¹	Nov 30 07:29¹
Halifax	UTC - 4 hours	Oct 1 18:05¹	Oct 31 11:49¹	Nov 30 05:29
New_York	UTC - 5 hours	Oct 1 17:05¹	Oct 31 10:49¹	Nov 30 04:29
Chicago	UTC - 6 hours	Oct 1 16:05¹	Oct 31 09:49¹	Nov 30 03:29
Edmonton	UTC - 7 hours	Oct 1 15:05¹	Oct 31 08:49¹	Nov 30 02:29
Los_Angeles	UTC - 8 hours	Oct 1 14:05¹	Oct 31 07:49¹	Nov 30 01:29
Hawaii	UTC - 10 hours	Oct 1 11:05	Oct 31 04:49	Nov 29 23:29
¹ Daylight saving time is in effect.

As you can see, most of the world has a Blue Moon on 31 October. The exceptions are New Zealand and central and eastern Australia. Their time zones are sufficiently far ahead of GMT that the second Full Moon occurs in the early hours of 1 November instead of 31 October. As a result, in these time zones it is November which has two Full Moons.

Once in a Blue Moon

The Blue Moon of 2020