Enjoying EarthSky? Subscribe.

116,465 subscribers and counting ...

Super Harvest Moon lights up the night of September 8-9

This morning's setting moon - September 8, 2014 at 5:30 a.m. - by Lance Bullion.

Tonight for September 8, 2014

Lance Bullion captured the image at the top of this post this morning – September 8, 2014 – at 5:30 a.m. It’s the beautiful setting Harvest Moon, colored by the extra thickness of Earth’s atmosphere in the direction toward the horizon. You’ll see a similarly colored rising Harvest Moon moon this evening, if you catch tonight’s moon shortly after moonrise. Simply stated, the Harvest Moon is the full moon that falls the closest to autumnal equinox. This year’s Harvest Moon qualifies as a supermoon, too, because the moon is turning full less than one day after reaching lunar perigee – the moon’s closest point to Earth for the month. Look for this full moon to usher in wide-ranging spring tides along the ocean coastlines for the next several days. That is, the high tides will climb extra high and the low tides fall exceptionally low.

Click here to read more about supermoons

In 2014, the September full moon narrowly beats out the October full moon for the honor of being the Harvest Moon. Had the September and October full moons occurred 16 hours earlier this year, the October 2014 full moon would have claimed the Harvest Moon title. The last October Harvest Moon was October 4, 2009, and will next occur on October 5, 2017.

In 2014, the moon reaches the crest of its full phase on September 9 at 1:38 Universal Time. That’s tonight – September 8 – at precisely 9:38 p.m. EDT, 8:38 p.m. CDT, 7:38 p.m. MDT or 6:38 p.m. PDT. For much of North America, the moon will turn precisely full on the evening of September 8. (See worldwide map below.)

No matter what time your clock says when the moon reaches the crest of its full phase tonight, and no matter where you live worldwide, you’ll see a full-looking moon lighting up the night tonight from dusk until dawn.

The lunar calendars are coming! They’ll help you the moon phases throughout the year.

Looking for a tide chart? EarthSky recommends…

Spring tides generally maximize the difference between high and low tide a few days after new moon and full moon. Meanwhile, neap tides usually minimize the difference between high and low tide a few days after the first and last quarter moons. For more, read Tides, and the pull of the moon and sun

Spring tides generally maximize the difference between high and low tide a few days after new moon and full moon. Meanwhile, neap tides usually minimize the difference between high and low tide a few days after the first and last quarter moons. For more, read Tides, and the pull of the moon and sun

The Harvest Moon isn’t just a one-night event. Watch for a bright moon tonight, tomorrow night and the night after. The Harvest Moon is known for rising shortly after sunset for several evenings in a row.

That’s why the Harvest Moon has been celebrated throughout the centuries and millennia, even before it came to be called a Harvest Moon. It provides several nights of dusk-until-dawn moonlight around the time the crops are being gathered from the fields. Before the advent of electricity, farmers of old counted on the Harvest Moon to help them see by moonlight, as they brought in their crops during the season of waning daylight.

Day and night sides of Earth at instant of full moon

Day and night sides of Earth at instant of full moon (2014 September 9 at 1:38 Universal Time). Image credit: Earth and Moon Viewer

Day and night sides of Earth at instant of full moon (2014 September 9 at 1:38 Universal Time). Image via Earth and Moon Viewer

One of you asked:

Is the phase of the moon consistent across the United States? Recently, on a trip to the California coast we saw a full moon, but it did not appear to be in the same phase just one day later in the western Pennsylvania sky.

The moon’s phase does appear the same as seen from across the U.S. – even from across the world – more or less. When the moon is full, for example, it’s more or less full for all of us. So looking up at night unites us all, across the planet. We all see the moon as nearly full around now, for example.

The moon’s phase is continuously changing, though, even if that change isn’t perceptible to the eye. From one night to the next, the moon can definitely appear different in phase from the previous night. What’s more, your perception of the moon might be affected by other things – for example, by whether you’re seeing the moon in twilight or late at night, whether it’s peeking from behind trees or shining in solitary splendor, whether it’s a big reddish moon low in the sky or a smaller whiter moon closer to overhead.

There are seasonal variations, too. Around the time of full moon in spring, the moon rises much later one evening than it does the evening before. To me, that gives the impression of a moon that’s waning rapidly. In late summer and fall, the opposite is true. At middle and far northern latitudes in the Northern Hemisphere, full moons in September and October are characterized by a shorter-than-average time between successive moonrises. These moonrises close to the time of sunset – around the time of the full moon in September and October – are the essence of the Harvest Moon phenomenon.

Bottom line: Each September and October, around the time of full moon, the moon rises near the time of sunset for several evenings in a row for us in the Northern Hemisphere. It’s almost as if the months of September and October each have several nights of full moon, instead of just one. This is the Harvest Moon phenomenon. In 2014, observe this phenomenon around September 8-10.

Minor lunar standstill lessens impact of 2014 Harvest Moon

Understanding moon phases

Looking for a sky almanac? EarthSky recommends…

Read more about the Harvest Moon

Help support EarthSky! Visit the EarthSky store for to see the great selection of educational tools and team gear we have to offer.