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Hunter's Moons distinguish themselves from other full moons by their rising times. In autumn, around the time of full moon, the time between successive moonrises (from one night to the next) is shorter than usual.
• However, the moon is now approaching a point in its 18.6-year cycle that tempers the distinguishing characteristic of the Harvest and Hunter's Moons. That's the lunar standstill mentioned above.
• The Harvest and Hunter's Moons are the result of the narrow angle of the ecliptic - or sun and moon's path - with respect to the evening horizon in autumn. Unlike Earth's moon, many moons in the solar system do orbit above the equator of their parent planets. If our moon did likewise - orbited around the Earth's equator - then the moon would always rise due east and set due west. But our moon's orbit is inclined to the plane of the Earth's equator and thus gives rise to more northerly moonrises after the Northern Hemisphere's Harvest and Hunter's Moons.
• In the days after full moon, in September and October, the moon (which always moves eastward in orbit) always travels farther north in declination (in other words, northward from the sky's equator) for a number of days. Hence the reason for the Harvest and Hunter's Moon phenomenon. After this year's full Hunter's Moon on October 29, the moon will continue moving northward in declination. It'll reach its northernmost declination on the sky's dome - in this case, 21o north of the celestial equator - on November 2, 2012. If the moon always stayed at the same declination, it'd always rise at the same point on the horizon and would not exhibit earlier-than-usual rising times. But it doesn't. It's this northward movement of the moonrise along the eastern horizon that gives northerly latitudes several days of dusk-to-dawn moonlight after the Harvest and Hunter's full moons. Read more about the October 29 Hunter's Moon on yesterday's night sky post.
• The inclination of the moon's orbital path to the plane of the Earth's equator changes over a cycle of 18.6 years. For instance, in the year 2006, the moon in its monthly travels swung from about 28.5 degrees south to 28.5 degrees north of the Earth's equator. Sometimes this extreme inclination is called a major lunar standstill. The greater inclination of the moon's orbit accentuates the effect of the Harvest and Hunter's Moons phenomenon.
• In the year 2015, in contrast, the moon's monthly travels will only take the moon from about 18.5 degrees south to 18.5 degrees north of the Earth's equator. This minimal inclination of the moon's orbit is sometimes called a minor lunar standstill. A minor lunar standstill acts to lessen the effect of the Harvest and Hunter's Moons.
• We contrast the 2005 Hunter's Moon with the 2015 Hunter's Moon in the tables at the bottom of this page. In 2005, the full Hunter's Moon occurred on October 17,

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