The October full moon, called the Hunter’s Moon, will brighten the sky on October 9, the same day that the planet Mercury reaches its greatest height in the predawn sky and the day after it reaches its greatest elongation (separation) from the sun.
This means that on the night of a full moon, Mercury will be visible before sunrise and at an altitude sufficient to make it easier than usual for observers at mid-northern latitudes.
According to the US Naval Observatory, the moon will officially become full on October 9 at 4:55 pm EDT (20:55 UTC). (will open in a new tab). For New York observers, the moon will rise on this day at 18:34 local time. (will open in a new tab) and will enter the next morning at 7:41 am. Rising about 9 minutes after sunset (which will happen at 18:25), the Moon will be in the constellation of Pisces, Pisces. Pisces is not a particularly bright constellation, so it will be largely eclipsed by the moon itself, as the bright light makes many nearby objects hard to see.
Related: Brightest planets in October night sky: how to see them (and when)
Considering that it is autumn in the northern hemisphere, the Moon will reach its maximum height – also known as the meridian crossing – around 55 degrees. (will open in a new tab) in New York around 1:01 am October 10th. As it moves south, the Moon’s altitude will increase until it reaches a maximum near the equator, before losing altitude again as it moves south. In Miami, for example, the moon reaches 70 degrees at 1:27 am on October 10th. (will open in a new tab)when he crosses the meridian there.
In Quito, the moon (which technically becomes full at 15:55 local time on October 9) crosses the meridian on October 10 at 00:20 and reaches an altitude of 83 degrees. (will open in a new tab). Moving further south to Buenos Aires, the maximum height of the full moon on October 10 will be 49 degrees. (will open in a new tab).
Mercury’s greatest elongation
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Mercury will reach its highest altitude for observers in the Northern Hemisphere on October 9 and 10. From New York on October 10, Mercury rises at 5:26 am and the sun rises at 6:59 am. This means that by sunrise the planet will be 17 degrees (will open in a new tab)It is reported in-the-sky.org. The planet will have a magnitude of -0.6, slightly brighter than the star Vega. Civil twilight, when the sun is 6 degrees below the horizon and the sky begins to lighten, occurs at 6:34 am. At this point, Mercury will be about 12 degrees south of east.
Mercury will be in the constellation Virgo; to find it, you can look for the “crescent” shape of the stars that marks the head of the lion Leo, which will be high in the east and look below him towards the horizon. Mercury forms a rough triangle with Regulus on the right and Denebola on the left, and Mercury marks a point at the bottom.
From more southerly latitudes, Mercury will be more difficult to observe; from Quito, for example, at sunrise it will be only 15 degrees above the horizon, and from Buenos Aires even lower – about 7 degrees.
Other visible planets in October
Venus is near superior conjunction when it is on the opposite side of the Sun from Earth; the planet will be lost in bright sunlight at dawn and not immediately visible.
Mars rises in New York at 21:44 on the evening of October 9th. (will open in a new tab). The red planet is in the constellation of Taurus and will be to the left of Aldebaran, the brightest star in the rising constellation.
Jupiter is visible almost all night; The moon approaches the planet, passing 2 degrees south of it on October 8 at 2:11 pm ET. By the next day, the planet will be to the right of the full moon. On October 9, Jupiter rises at 17:54. (will open in a new tab) in New York and sits down the next morning at 5:46 am. Jupiter is in Pisces, and its steady, bright light will be easily distinguishable among the dimmer Pisces stars.
Saturn rises in the afternoon in New York around 4:07 pm and sets at 2:06 am October 10th. Saturn, like Jupiter, is in a faint constellation that makes the planet itself more distinct. Saturn will be about 30 degrees above the southern horizon by 22:00. At mid-northern latitudes, Saturn forms a rough line with Jupiter and the Moon across most of the southern sky, with Saturn on the right (west) and the Moon on the east side.
October stars and constellations
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Around 10:00 pm on October 9, the Summer Triangle is still visible, but it is in the western half of the sky, and Deneb, the brightest star in Cygnus Cygnus, is the tallest of the three stars that make up the asterism. Below and to the right of Deneb will be Vega, in Lyra Lyra, and to the left of Vega Altair, the “eye” of the Eagle. Meanwhile, moving to the left (south), one can see Fomalhaut, the alpha star in the Austrian Pisces, Southern Pisces. Fomalhaut will be lower and to the left of Saturn.
Looking east, the Chapel in the Charioteer, the Charioteer, rises, revealing the winter stars. If you turn further north and up from the Chapel, you can see the letter “W” of Cassiopeia, which points to the North Star, Polaris, in Ursa Minor. Although there are no “pointers” in Cassiopeia as there are in Ursa Major, if you draw a rough line from the middle top of the “W” to the left and down, you can reach the North Star. Meanwhile, the Big Dipper will be close to the horizon and will become more and more visible over time.
How Hunter’s Moon Got Its Name
(Image credit: Jose Zarkos Palma)
The October Full Moon is often referred to as the Hunter’s Moon, according to the Old Farmer’s Almanac, because this moon falls at the start of the hunting season for many wild animals. The traditional full moon names often reflect the local environment and history; according to the Ontario Native Coalition, the Ojibwe called the October full moon “Mskawji Ghizis” or “Freezing Moon” because the first frost occurs in October in their traditional territory in the Great Lakes region. The Cree people called it “Pimahamovipisim” (Migrating Moon) as in North America many bird species begin migrating south for wintering in mid-autumn.
In the Pacific Northwest, the Tlingit called the October full moon “Dis Tlein” (Big Moon), and the Haida called the moon “Kalk Kungaai” or “Ice Moon,” according to the Tlingit Moon and Tide Study Resource. (will open in a new tab)published by the University of Alaska Fairbanks.
In the traditional Chinese calendar, October 9 falls on the 9th lunar month, called Juyue or Chrysanthemum Month, as it is on this day that the flower with that name blooms. The full moon will also mark the start of the Jewish holiday of Sukkot, when Israelis were traditionally called to make a pilgrimage to the Temple in Jerusalem. Jews sometimes celebrate by building a temporary building (called a sukkah) in which food is served; sometimes people sleep in them to commemorate the temporary homes the Jews lived in during their time in the desert after their flight from Egypt.
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