Best 2011 Harvest Moon pictures from EarthSky Friends
Waters asked:
When will we see the Harvest Moon in 2011?
And the answer is … tonight! Over the years, we’ve seen lots of informal uses of the term Harvest Moon. Some people will call all the full moons of autumn by that name. And so they should. In autumn, the time of moonrise is close to the time of sunset for several evenings in a row, around the time of full moon. It’s as if there are several full moons during each autumn month.
So for example the moon you might have seen last night (September 10) looked very full and round in the sky. Did you call it a full moon? Did someone say it was the Harvest Moon? It probably looked like one!
Moonrise over the mountain in North Woodstock, NH. from EarthSky Facebook friend North Woodstock, NH.
Astronomers are scientists, though, and it’s no surprise that, to them, the term “full moon” or the name “Harvest Moon” means something very specific. To astronomers, the Harvest Moon is the full moon closest to the September equinox.
In 2011, this equinox takes place on September 23. The closest full moon to the autumn equinox reaches the crest of its full phase on September 12 at 9:27 Universal Time. That means the moon turns exactly full for us in the continental U.S. in the wee hours before sunrise tomorrow, on Monday, September 12. By U.S. clocks, that’s 5:27 a.m. Eastern Daylight Time, 4:27 a.m. Central Daylight Time, 3:27 a.m. Mountain Daylight Time or 2:27 a.m. Pacific Daylight Time.
Day and night sides of Earth at instant of Full Harvest Moon (2011 September 12 at 9:27 Universal Time)
Image Credit: Earth and Moon Viewer
No matter where you live worldwide, however, you’ll see a full-looking moon shining from dusk until dawn tonight. It’ll rise in the east around sunset, climb highest up around midnight and will set in the west around sunrise. At the vicinity of full moon, the moon – as always – stays out all night long. Is tonight’s moon the Harvest Moon. Sure!
Why are the full moons so special in autumn? Around the time of the autumn equinox, the ecliptic – or the path of the sun, moon, and planets – makes a narrow angle with the horizon at sunset and early evening.
Moonrise over Smoke Lake, Algonquin Park, Ontario, Huntsville Canada, from EarthSky Facebook friend Adam Falardeau.
Every full moon rises around the time of sunset, and on average each successive moonrise comes about 50 minutes later daily. But, on September and October evenings – because of the narrow angle of the ecliptic to the horizon – the moon rises much sooner than the average. So, instead of rising 50 minutes later in the days after full moon, the waning moon might rise only 30 minutes later, or less, for several days in a row (at mid-northern latitudes). At far northern latitudes – like at Fairbanks, Alaska – the moon actually rises at nearly the same time for days on end.
That fact was important to people in earlier times. For farmers bringing in the harvest, before the days of tractor lights, it meant there was no long period of darkness between sunset and moonrise for several days after full moon. And that meant farmers could work on in the fields, bringing in the crops by moonlight. Hence the name Harvest Moon.
At our mid-northern latitudes, watch for the Harvest Moon to shine from dusk until dawn for the next few to several days, starting tonight. Enjoy the 2011 Harvest Moon!
I have found disagreement on-line. I’ve seen next month’s full moon named The Harvest Moon, and this month’s The Corn Moon.
I suppose there is no true authority for this.
Howard, yes, there seems to be some confusion this year. But in my 35 years of writing about the sky, the definition for Harvest Moon has always been the full moon CLOSEST to the autumn equinox, which comes this year on September 23. The full moon after that is always called the Hunter’s Moon.
So sometimes the Harvest Moon comes after the equinox and sometimes before. This year’s Harvest Moon is pretty early – but tonight’s moon is the closest full moon to the equinox. The full moon of October – according to traditional skylore – would not be the Harvest Moon because it is farther from the equinox than tonight’s moon. It would be the Hunter’s Moon – because it follows tonight’s Harvest Moon.
But, as you say … there’s no true authority. It’s just skylore! BOTH tonight’s moon and the full moon of October 11 will display the same attributes. Both will shortly after sunset for several evenings in a row and look round and full in the night sky – as though we have several nights in a row of full moon. Enjoy!
- Deborah
Depending on the year, the Harvest Moon can come anywhere from two weeks before to two weeks after the autumn equinox. (The northern hemisphere’s autumn equinox occurs annually on or near Sept. 23.) In some years the Harvest Moon can even fall in early October, as it did in 2009. More often than not, however, the northern hemisphere’s Harvest Moon occurs in September.
Thanks a lot for your insight…is the moon still that we see only one side of it doesn’t it rotate? And the sun too
Not really. the moon does rotate but it rotates at the same speed thhat it revolves around the Earth, so we always se the same side of the moon.
The sun does rotate, we just don’t notice because it is lit on all sides and no, easy to spot, landmarks are shown.
Get out and see the moon. If it is darker on the left, it is not yet full. If it is darker on the right, it is past full. If you can’t tell the difference with good seeing, it is full.