New Zealand Has Only One Blue Moon in 2018

Summary: New Zealand has only one blue moon in 2018, which is a double blue moon year for time zones that are not 11 hours ahead of Coordinated Universal Time.

Prior to April 2018's second full, or blue, moon, New Zealand's last blue moon happened Friday, July 31, 2015: Andrew Bell @andrewbell_8, via Twitter July 31, 2015

New Zealand has only one blue moon in 2018, a double blue moon year for other time zones that are not 11 hours ahead of Coordinated Universal Time (UTC), the world’s time standard.

Astronomer David Harper on his website, Obliquity, explains that, unlike most of the world, New Zealand does not experience 2018 as a year of two calendrical blue moons. A calendrical blue moon designates the second of two full moons within the same month. As a variant definition, a seasonal blue moon signifies the third of four full moons within the same three-month season.

New Zealand’s two main islands, North Island and South Island, fall within the New Zealand Time Zone. The zone comprises New Zealand Daylight Time (NZDT) and New Zealand Standard Time (NZST).

New Zealand Daylight Time’s UTC offset of UTC +13 tells that the daylight saving component is 13 hours ahead of Coordinated Universal Time. New Zealand Standard Time’s UTC offset of UTC +12 reveals that the zone’s standard time is 12 hours ahead of Coordinated Universal Time.

New Zealand’s daylight saving component is in effect until 3 a.m. NZDT, Sunday, April 1. At 3 a.m. NZDT, Sunday, April 1, New Zealand timepieces are set back one hour, to 2 a.m. NZST. New Zealand Standard Time begins at 2 a.m. NZST, Sunday, April 1.

According to Coordinated Universal Time, which has the same time offset (UTC +0) as Greenwich Mean Time (GMT), 2018’s first four months, January through April, host five full moons. The year’s first five full moons open and close January, skip February, begin and end March, and close April.

New Zealand’s first five full moons in 2018 are spread over the year’s first four months. Unlike Coordinated Universal Time and time zones that are less than 11 hours ahead of UTC, New Zealand Daylight Time does not experience February as a full moonless-month.

David Harper’s Obliquity site selects Auckland, New Zealand’s largest urban area, as representative of the island country’s different blue moon experience. Auckland’s first 2018 full moon happened Tuesday, Jan. 2, at 3:24 p.m. NZDT (02:24 UTC).

New Zealand Daylight Time, however, disqualifies January as a blue moon month by slipping Auckland’s second 2018 full moon into February. Auckland’s second 2018 full moon happens at 2:26 NZDT, Thursday, Feb. 1 (Wednesday, Jan. 31, at 13:26 [1:26 p.m.] UTC).

New Zealand Daylight Time allows Auckland’s third 2018 full moon to agree with Coordinated Universal Time’s early March date. Auckland’s third 2018 full moon occurs Friday, March 2, at 1:51 p.m. NZDT (00:51 [12:51 a.m.] UTC).

April favors Auckland as the North Island city’s only blue moon month in 2018. Auckland’s first full moon happens Sunday, April 1, at 01:37 a.m. NZDT as New Zealand’s fourth 2018 full moon. The month’s second full, or blue, moon occurs Monday, April 30, at 12:58 p.m. NZST, as New Zealand’s fifth 2018 full moon.

According to Coordinated Universal Time, April resumes the lunar cycle’s norm as a one full moon month. Coordinated Universal Time’s fifth 2018 full moon happens Monday, April 30, at 00:58 (12:58 a.m.) UTC.

New Zealand claims two additional time zones. Both time zones allow for April as the zones’ only 2018 blue moon month.

The Chatham Islands, located about 750 kilometers (about 466 miles) east of New Zealand’s South Island, lies in the Chatham Island Time Zone. The islands’ time zone comprises Chatham Island Daylight Time (CHADT) and Chatham Island Standard Time (CHAST).

With an offset of UTC +13:45, Chatham Island Daylight Time is 13 hours 45 minutes ahead of Coordinated Universal Time. Chatham Island Standard Time’s UTC offset is UTC +12:45, making its time 12 hours 45 minutes ahead of Universal Coordinated Time.

Chatham Island, the largest of the archipelago’s 11 islands, observes April’s second full, or blue moon Monday, April 30, at 1:43 p.m. CHAST.

New Zealand’s third time zone is observed by New Zealand’s non-self-governing territory of Tokelau. The remote trio of coral atolls is located in the southern Pacific Ocean, at a distance of about 3,200 kilometers (about 1,988 miles) northeast of New Zealand’s North Island.

Tokelau Time does not have a daylight saving component. Tokelau Time’s offset of UTC +13 signifies that the New Zealand dependency’s time zone is 13 hours ahead of Coordinated Universal Time.

Tokelau welcomes April’s blue moon Monday, April 30, at 1:58 p.m. TKT.

The takeaway for New Zealand having only one blue moon in 2018 is that New Zealand’s April blue moon is the year’s last blue moon, as Coordinated Universal Time’s second blue moon shows up in March.

New Zealand’s Southern Alps-dominated South Island and Northland Peninsula-dominated North Island; Moderate Resolution Imaging Spectroradiometer (MODIS), NASA’s Terra satellite; Thursday, Oct. 23, 2003: Jacques Descloitres/MODIS Rapid Response Team, NASA/GSFC, Public Domain, via Wikimedia Commons

Acknowledgment

My special thanks to talented artists and photographers/concerned organizations who make their fine images available on the internet.

Image credits:

Prior to April 2018's second full, or blue, moon, New Zealand's last blue moon happened Friday, July 31, 2015: Andrew Bell @andrewbell_8, via Twitter July 31, 2015, @ https://twitter.com/andrewbell_8/status/627068595462254592

New Zealand’s Southern Alps-dominated South Island and Northland Peninsula-dominated North Island; Moderate Resolution Imaging Spectroradiometer (MODIS), NASA’s Terra satellite; Thursday, Oct. 23, 2003: Jacques Descloitres/MODIS Rapid Response Team, NASA/GSFC, Public Domain, via Wikimedia Commons @ https://commons.wikimedia.org/wiki/File:New_Zealand_23_October_2002.jpg

For further information:

Andrew Bell ‏@andrewbell_8. "Blue Moon. You saw me standing alone!" and behind lots of clouds in New Zealand." Twitter. July 31, 2015.
Available @ https://twitter.com/andrewbell_8/status/627068595462254592

Harper, David. “Once in a Blue Moon: The Double Blue Moon of 2018.” Obliquity > Interactive Astronomy.
Available @ https://www.obliquity.com/astro/blue2018.html

Marriner, Derdriu. “Blue Moon Month January 2018 Opens New Year With Two Full Moons.” Earth and Space News. Wednesday, Dec. 27, 2017.
Available @ https://earth-and-space-news.blogspot.com/2017/12/blue-moon-month-january-2018-opens-new.html

Marriner, Derdriu. “New South Wales Mostly Has Only One Blue Moon Month in 2018.” Earth and Space News. Wednesday, March 28, 2018.
Available @ https://earth-and-space-news.blogspot.com/2018/03/new-south-wales-mostly-has-only-one.html

Marriner, Derdriu. “Super Blue Moon Wednesday, Jan. 31, Is First of Two 2018 Blue Moons.” Earth and Space News. Wednesday, Jan. 31, 2018.
Available @ https://earth-and-space-news.blogspot.com/2018/01/super-blue-moon-wednesday-jan-31-is_31.html

McClure, Bruce. “Year’s 2nd Blue Moon on March 31.” EarthSky > Tonight. March 31, 2018.
Available @ http://earthsky.org/tonight/years-2nd-blue-moon-on-march-31