As the Moon orbits Earth, its changing geometry with respect to the Sun produces the characteristic phases. This composite image is a mosaic made from 25 individual photos of the Moon and illustrates its phases over one synodic month. For complete details about this image, see Moon Phases Mosaic. The individual images included in this composite can be found in the Moon Phases Gallery. For more composites, see Moon Phases Mosaics. Photo copyright 2012 by Fred Espenak.
As the Moon orbits Earth, its changing geometry with respect to the Sun produces the Moon’s characteristic phases (New Moon, First Quarter, Full Moon and Last Quarter). One orbit of the Moon relative to the Sun (the synodic month) has a mean duration of 29.53 days.
The table below lists the date and time of the Moon’s phases throughout 2014. The time of each phase is given in Greenwich Mean Time or GMT (a.k.a. Universal Time or UT). To convert GMT to Eastern Standard Time (EST) just subtract 5 hours. To convert GMT to other time zones, visit Time Zones.
Moon Phases for 2014 (GMT)
New Moon First Quarter Full Moon Last Quarter
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Jan 1 06:14 Jan 7 22:39 Jan 15 23:52 Jan 24 00:19
Jan 30 16:39 Feb 6 14:22 Feb 14 18:53 Feb 22 12:15
Mar 1 03:00 Mar 8 08:27 Mar 16 12:09 Mar 23 20:46
Mar 30 13:45 Apr 7 03:31 Apr 15 02:42 Apr 22 02:52
Apr 29 01:14 May 6 22:15 May 14 14:16 May 21 07:59
May 28 13:40 Jun 5 15:39 Jun 12 23:11 Jun 19 13:39
Jun 27 03:09 Jul 5 06:59 Jul 12 06:25 Jul 18 21:08
Jul 26 17:42 Aug 3 19:50 Aug 10 13:09 Aug 17 07:26
Aug 25 09:13 Sep 2 06:11 Sep 8 20:38 Sep 15 21:05
Sep 24 01:14 Oct 1 14:33 Oct 8 05:51 Oct 15 14:12
Oct 23 16:57 Oct 30 21:48 Nov 6 17:23 Nov 14 10:16
Nov 22 07:32 Nov 29 05:06 Dec 6 07:27 Dec 14 07:51
Dec 21 20:36 Dec 28 13:31
I’ve generated a table of the Moon’s phases covering 100 years at Moon’s Phases – 21st Century (GMT). Similar 100-year tables for other time zones include Eastern Standard Time (EST), Central Standard Time (CST), Mountain Standard Time (MST), and Pacific Standard Time (PST).
What surprises many people is that the length of the synodic month can vary by over 6 hours from its mean value of 29.5306 days (29 days 12 hours 44 minutes). The table below gives the date of New Moon, the length of the synodic month, and the difference from the synodic month’s mean value for every synodic month in 2014. For instance, the first synodic month of 2014 is 2 hours 20 minutes shorter than the mean while the nineth month (beginning Aug 25) is 3 hours 17 minutes longer than the mean.
Synodic Months for 2014
Date/Time of Length of Dif. from
New Moon (GMT) Synodic Month Mean Month
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2014 Jan 01 11:14 29d 10h 24m -02h 20m
2014 Jan 30 21:39 29d 10h 21m -02h 23m
2014 Mar 01 08:00 29d 10h 45m -01h 59m
2014 Mar 30 18:45 29d 11h 30m -01h 14m
2014 Apr 29 06:14 29d 12h 26m -00h 18m
2014 May 28 18:40 29d 13h 28m +00h 44m
2014 Jun 27 08:08 29d 14h 33m +01h 49m
2014 Jul 26 22:42 29d 15h 31m +02h 47m
2014 Aug 25 14:13 29d 16h 01m +03h 17m
2014 Sep 24 06:14 29d 15h 43m +02h 59m
2014 Oct 23 21:57 29d 14h 36m +01h 52m
2014 Nov 22 12:32 29d 13h 04m +00h 20m
2014 Dec 22 01:36 29d 11h 38m -01h 06m
The year 2008 had even greater extremes in the synodic month – from 5 hours 48 minutes shorter, to 6 hours 49 minutes longer than the mean value. So what causes these variations? The explanation lies in the fact that the Moon’s orbit is elliptical. If New Moon occurs when the Moon is nearest to Earth (perigee), then the synodic month is shorter than normal. On the other hand, if New Moon occurs when the Moon is farthest from Earth (apogee), then the synodic month is longer than normal. Furthermore, the orientation of the Moon’s ellipse-shaped orbit slowly rotates in space with a period of about 18 years. A more detailed discussion on this topic can be found at Moon’s Orbit and the Synodic Month. You can also find the duration of every synodic month this century at Length of the Synodic Month: 2001 to 2100.
Because the Moon orbits Earth in ~29.5 days with respect to the Sun, its daily motion against the background stars and constellations is quite rapid. It averages about 12.2° per day. A table giving the Moon’s daily celestial coordinates throughout the year can be found at 2014 Moon Ephemeris. This table lists a lot of other details about the Moon including its daily distance, apparent size, libration, phase age (days since New Moon) and the phase illumination fraction. See the above table for descriptions of all these terms.
A Super Moon is a Full Moon that occurs within 90% of the Moon’s closest approach to Earth in a given orbit. The Full Moon then appears especially big and bright since it subtends its largest apparent diameter as seen from Earth. The table below lists the Super Moons occurring in 2014.
Super Moons for 2014
Full Moon Distance Diameter Relative
(GMT) (km) (arc-min) Distance
Jun 13 04:11 365038 32.73 0.931
Jul 12 11:25 358975 33.29 0.985
Aug 10 18:09 356898 33.48 1.000
Sep 09 01:38 359182 33.27 0.983
Oct 08 10:51 365659 32.68 0.925
The Relative Distance listed in this table expresses the Moon’s distance as a fraction between apogee (0.0) and perigee (1.0). For much more on Super Moons and a complete list of them for this century, see Full Moon at Perigee (Super Moon): 2001 to 2100.
Besides its obvious phases, the Moon also undergoes some additional extremes in its orbit including: Perigee and Apogee, Ascending/Descending Nodes, and Lunar Standstills. Each of the above links covers lunar phenomena for the entire 21st Century.
One of the first projects I tacked upon completing Bifrost Observatory in 2010 was to photograph the Moon’s phases every day for a complete month. Of course, the weather doesn’t always cooperate (even from sunny Arizona) so it actually took several months to complete the project. You can see the results at the Moon Phases Gallery. Clicking on any of the thumbnails pictures will give you an enlarged image with complete technical details. You can also visit Moon Phases Mosaics to see composites showing the Moon’s phases over a complete synodic month.
Last year (2013), NASA’s Lunar Reconnaissance Orbiter (LRO) team created clever animation using data from both the LRO and Clementine missions. It illustrates the Moon’s phases throughout 2013 at 1-hour intervals.
Besides presenting the Moon’s phase and apparent size, the video shows the Moon’s orbital position with respect to the Sun and Earth, and it’s distance from Earth. As the Moon orbits Earth, it appears to wobble and tip on its axis. This motion is called libration and it allows us to see about 59% of the Moon’s surface. The major cause of libration is due to our changing line of sight because of the Moon’s elliptical orbit.
Finally, what discussion of the Moon would be complete without mentioning eclipses in 2014? There are two eclipses of the Moon and both of them are total. The first occurs on April 15 and the second, six months later on October 8. Both of them are well placed for viewing from North America. There are also two solar eclipses. The first is an annular eclipse in Antarctica on April 29 (a partial eclipse is visible from Australia). The second is a partial solar eclipse visible from most of North America on October 23. I’ve written an article with more information at Eclipses During 2014.
Watching the Moon’s phases wax and wane as well as the occasional lunar eclipse can best be enjoyed with the naked eye and binoculars. And you don’t even need a dark sky since the Moon is easily visible from the heart of brightly lit cities.
The Moon phases and lunar phenomena discussed here were all generated with computer programs I’ve written (THINK Pascal running on a Macintosh G4) using Astronomical Algorithms (Jean Meeus).
– Fred Espenak