September 2020: The Next Full Moon is the Corn, Fruit, Barley, and Hungry Ghost Moon

The Next Full Moon is the Corn, Fruit, Barley, and Hungry Ghost Moon; the end of Onam; the start of Pitri Paksha; Modhu Purnima; Binara Pura Pasalosvaka Poya; and the GRAIL, LADEE, and OSIRIS-REx Moon.

The next full Moon will peak after midnight on Wednesday morning, Sept. 2, 2020, appearing "opposite" the Sun (in Earth-based longitude) at 1:22 a.m. EDT. The Moon will appear full for about three days around this time, from Monday evening through Thursday morning.

The Maine Farmer's Almanac first published Native American names for the full Moons in the 1930s. Over time these names have become widely known and used. According to this almanac, as the full Moon in September and the last full Moon of summer, the Algonquin tribes in what is now the northeastern USA called this the Corn Moon, as this was the time for gathering their main staple crops of corn, pumpkins, squash, beans, and wild rice.

European names for this full Moon are the Fruit Moon, as a number of fruits ripen as the end of summer approaches, and the Barley Moon, from the harvesting and threshing of the barley.

This full Moon corresponds to the Chinese Hungry Ghost Festival. The seventh month of the Chinese calendar is the Ghost Month and the fifteenth day of this month (a full Moon day) is called Ghost Day, on which ghosts and spirits, including those of deceased ancestors, come out to visit the living.

For Hindus in Kerala, India, this full Moon marks the end of the 10-day celebration of Onam, which began on Aug. 22, 2020. This full Moon also marks the start of Pitri (or Pitru) Paksha (fortnight of the ancestors) during which Hindus pay homage to their ancestors, especially through food offerings. Pitri Paksha starts with the full Moon in the lunar month of Bhadrapada and ends with the new Moon.

For some Buddhists in Bangladesh and Thailand, this full Moon is Modhu Purnima, the Honey Full Moon or the Honey-offering Festival. This festival is tied to a legend that an elephant and a monkey fed the Buddha when he was in the forest to bring peace between two factions, with the elephant offering fruit and the monkey offering a honeycomb.

In Sri Lanka, this full Moon is the Binara Pura Pasalosvaka Poya Day, commemorating the establishment of the Buddhist Bikkhuni Order.

Newer names for this full Moon are the GRAIL Moon and the LADEE Moon. On Sept. 10, 2011, NASA's twin Gravity Recovery and Interior Laboratory (GRAIL) spacecraft started their voyage toward the Moon on a Delta II launch vehicle. On Sept. 6, 2013, NASA's Lunar Atmosphere and Dust Environment Explorer (LADEE) spacecraft started its journey to the Moon on a Minotaur V launch vehicle.

In the last few years another tribe has given a special name to this full Moon. This tribe is geographically distributed but united in a common cause. This is the OSIRIS-REx Moon, in honor of NASA's Origins, Spectral Interpretation, Resource Identification, and Security-Regolith Explorer (OSIRIS-REx) spacecraft launched four years ago on Thursday, Sept. 8, 2016. OSIRIS-REx is currently at the near-Earth asteroid Bennu and will bring back samples for study in the laboratories of Earth, not just to answer questions we have today but to answer the questions of future generations of researchers, questions we have not thought of yet using laboratory instruments we have not invented yet. The OSIRIS-REx spacecraft completed its second sample collection rehearsal on Aug. 11, 2020, approaching about 131 feet (40 meters) above Bennu's surface. In October (currently scheduled for Oct. 20, 2020) OSIRIS-REx will contact the surface for several seconds and collect its samples. OSIRIS-REx will deliver these samples of Bennu back to Earth in September 2023.

In most lunisolar calendars the months change with the new Moon and full Moons fall in the middle of the lunar months. This full Moon is in the middle of the seventh month of the Chinese calendar and Elul, the twelfth month in the Hebrew calendar. Elul is a time of preparation for the High Holy Days of Rosh Hashanah and Yom Kippur. Customs include granting and asking others for forgiveness as well as beginning or ending all letters with the wish that the recipient will have a good year. This full Moon is near the middle of Muharram, the first month of the Islamic year, one of the four sacred months during which warfare is forbidden.

As usual, the wearing of suitably celebratory celestial attire is encouraged in honor of the full Moon. And you might want to gather your fruits, vegetables, and other staples; avoid war; remember your ancestors; ask for forgiveness; and let go of grudges. Here's wishing you have a good year!

As for other celestial events between now and the full Moon after next:

As summer ends and autumn begins, the daily periods of sunlight continue to shorten, shortening at their fastest around the equinox on Sept. 22, 2020.

For the Washington, DC area (the location of NASA Headquarters), on the day of the full Moon (Wednesday, Sept. 2, 2020) morning twilight will begin at 5:39 a.m. EDT, sunrise will be at 6:38 a.m., solar noon will be at 1:07:33 p.m. when the Sun will reach its maximum altitude of 58.7 degrees, sunset will be at 7:36 p.m., and evening twilight will end at 8:35 p.m. By the day of the full Moon after next (Thursday, Oct. 1, 2020) morning twilight will begin at 6:07 a.m., sunrise will be at 7:05 a.m., solar noon will be at 12:57:31 p.m. when the Sun will reach its maximum altitude of 47.6 degrees, sunset will be at 6:50 p.m., and evening twilight will end at 7:47 p.m.

Evenings this summer should be a great time for Jupiter and Saturn watching, especially with a backyard telescope. Jupiter was at its closest and brightest for the year on July 14, and Saturn at its closest and brightest on July 20, 2020, (called "opposition" because they were on the opposite side of Earth from the Sun). Both will appear to shift toward the west over the summer months, making them visible earlier in the evening sky (and friendlier for backyard stargazing, especially if you have young ones with earlier bedtimes). With clear skies and a small telescope you should be able to see Jupiter's four bright moons, Ganymede, Callisto, Europa, and Io, shifting positions noticeably in the course of an evening. For Saturn, you should be able to see the brightly illuminated rings as well as the motions of Saturn's moons, particularly the largest moon, Titan.

Sept. 1

On the evening of Sept. 1, 2020 (the evening before the full Moon), as evening twilight ends (at 8:37 p.m. EDT for the Washington, DC area), the bright planet Jupiter and the fainter planet Saturn will appear in the south-southeast, with Jupiter to the right about 27 degrees above the horizon and Saturn on the left about 26 degrees above the horizon. The planet Mercury will have already set, but might be visible earlier in the evening (about 30 minutes after sunset), low on the western horizon. The bright star appearing almost exactly overhead will be Vega, the brightest of the stars of the "Summer Triangle," appearing 86 degrees above the eastern horizon. The other bright stars of the Summer Triangle are Deneb, which will appear about 62 degrees above the horizon in the east-northeast, and Altair, which will appear about 53 degrees above the horizon in the southeast. If you are one of the approximately 20 percent of the American population living away from city lights, you might be able to see the Milky Way running across the sky from south-southwest to north-northeast after the sky darkens to full nightfall. As the lunar cycle progresses, the background of stars and planets will appear to shift toward the west, while Mercury will remain near the horizon, gradually shifting from the west toward the west-southwest, and setting before evening twilight ends. Beginning Sept. 28, 2020, the planet Mars will be above the horizon in the east as evening twilight ends. By the evening of full Moon after next on Oct. 1, 2020, as evening twilight ends (at 7:47 p.m. EDT for the Washington, DC area), bright Jupiter will appear in the south about 28 degrees above the horizon with Saturn to the left of Jupiter at about 29 degrees above the horizon. Mars will appear in the east at about 2 degrees above the horizon. The Summer Triangle of Vega, Deneb, and Altair will appear directly overhead.

Aug. 28-30

On Friday night into Saturday morning, Aug. 28 to 29, 2020, the bright planet Jupiter will appear near the waxing gibbous Moon, with the fainter planet Saturn appearing nearby. As evening twilight ends (at 8:44 p.m. EDT for the Washington, DC area), the Moon will appear in the south-southeast about 24 degrees above the horizon, with Jupiter appearing about 2 degrees above the Moon, and Saturn appearing about 9 degrees to the left. The Moon will reach its highest in the sky for the night at 9:55 p.m., appearing in the south about 26 degrees above the horizon. Jupiter and the Moon will set together in the west-southwest Saturday morning at 2:38 a.m., with Jupiter on the right and Saturn above the Moon.

Saturday evening, Aug. 29, 2020, will be (for the Washington, DC area, at least) the first evening when Mercury will be above the horizon about 30 minutes after sunset, an approximation of when it will start being visible in the evening sky.

Saturday evening into Sunday morning, Aug. 29 to 30, 2020, the planet Saturn will appear near the waxing gibbous Moon, with the brighter planet Jupiter appearing nearby. For the Washington, DC area, as evening twilight ends at 8:42 p.m. EDT, the Moon will appear in the south-southeast about 21 degrees above the horizon, with Saturn appearing to the upper right of the Moon and Jupiter appearing farther to the right. The Moon will reach its highest in the sky for the night at 10:49 p.m. and Jupiter will set first in the west-southwest Sunday morning at 2:34 a.m.

Even though they are not usually visible, I include in these Moon missives information about near-Earth objects (mostly asteroids) that may pass Earth within five lunar distances, because I find it interesting that we have discovered so many. Sometime in late August or early September 2020 (2020-Sep-01 16:12 UTC with 8 days, 8 minutes uncertainty), a near earth object (2011 ES4), between 73 to 162 feet (22 and 49 meters) across, will pass the Earth at between 0.2 and 41.2 lunar distances (nominally 0.3), traveling at 18,260 miles per hour (8.16 kilometers per second).

Sept. 2

On the morning of the full Moon on Wednesday, Sept. 2, 2020, as morning twilight begins (at 5:39 a.m. EDT for the Washington, DC area), the bright planet Venus will appear in the east about 29 degrees above the horizon. The planet Mars will appear in the southwest about 52 degrees above the horizon. The bright stars of the Summer Triangle will be setting in the northwest. The star appearing closest to overhead will be Capella, appearing 67 degrees above the horizon toward the east-northeast, with Aldebaran a close second at 62 degrees above the horizon toward the southeast. Capella, at 42.9 light-years from Earth, and Aldebaran at about 65 light-years, are both part of the local arm of our home galaxy, called the Orion-Cygnus Arm, which includes the brightest of the stars in our skies, Sirius (at 8.6 light-years from Earth), which will appear about 16 degrees above the horizon in the southeast. As the lunar cycle progresses, the background of stars will appear to shift toward the west. By the morning of the full Moon after next (Thursday, Oct. 1, 2020), as morning twilight begins (at 6:07 a.m.), the bright planet Venus will appear in the East about 27 degrees above the horizon near the bright star Regulus (Venus and Regulus will appear at their closest on the mornings of Oct. 2 and 3, 2020). The planet Mars will appear in the west-southwest at 26 degrees above the horizon. The constellation Orion will appear about 50 degrees above the horizon in the south, with the bright stars of the Orion-Cygnus Arm of our home galaxy spread from the south-southeast toward the northwest.

As mentioned above, the next full Moon will be early on Wednesday morning, Sept. 2, 2020.

Sept. 4

The morning of Friday, Sept. 4, 2020, will be when the planet Venus appears at its highest above the horizon for this apparition (29 degrees for the Washington, DC area) at the time morning twilight begins. Because the angle of the line between the Sun and Venus and the line of the horizon is becoming more perpendicular, the date when Venus is highest above the horizon as morning twilight begins is not the same date as when Venus and the Sun appear farthest apart as seen from Earth.

Sept. 5

On Saturday night into Sunday morning, Sept. 5 to 6, 2020, the planet Mars will appear quite near the waning gibbous Moon. For the Washington, DC area, the Moon and Mars will rise together in the east at about 9:30 p.m. EDT, with Mars about a degree to the left of the Moon. After midnight the pair will appear closest to each other, with Mars appearing above the Moon. The Moon will reach its highest in the sky on Sunday morning at 4:01 a.m., with Mars appearing 1.5 degrees to the right. Morning twilight will begin around 5:43 a.m., with Mars appearing about 2 degrees to the lower right of the Moon. From parts of southeastern South America and Antarctica, the Moon will pass in front of Mars.

Sept. 6

Early Sunday morning, Sept. 6, 2020, at 2:31 a.m. EDT, the Moon will be at apogee, its farthest from Earth for this orbit.

Sept. 8

On Tuesday midday, Sept. 8, 2020, at about 11:54 a.m. EDT (2020-Sep-08 15:54 UTC with 19 minutes uncertainty), a near-Earth object (2020 PT4), between 91 to 204 feet (28 and 62 meters) across, will pass the Earth at between 4.9 and 5.0 lunar distances (nominally 4.9), traveling at 28,090 miles per hour (12.56 kilometers per second).

Sept. 9-10

Tuesday night into Wednesday morning, Sept. 9 to 10, 2020, the bright star Aldebaran will appear to the lower left of the waning gibbous Moon. For the Washington, DC area, Aldebaran will rise in the east-northeast at 11:32 p.m. EDT, appearing about 8 degrees from the Moon. The pair will appear to shift gradually closer together until Aldebaran is lost in the glow of dawn on Wednesday morning, with morning twilight beginning at 5:46 p.m.

Thursday morning, Sept. 10, 2020, the waning Moon will appear half-full as it reaches its last quarter at 5:26 a.m. EDT.

Sept. 11

Although not visible without a telescope, Friday, Sept. 11, 2020, will be when the planet Neptune will appear at its closest and brightest for the year, opposite from the Sun as seen from Earth.

Sept. 13

On Sunday morning, Sept. 13, 2020, the bright star Pollux (one of the twins in the constellation Gemini) will appear about 5 degrees to the upper left of the waning crescent Moon. For the Washington, DC area, the Moon will rise in the east-northeast at 2:04 a.m. EDT and will be about 40 degrees above the horizon in the east at the time morning twilight begins at 5:50 a.m..

Sept. 14

On Monday morning, Sept. 14, 2020, the bright planet Venus will appear about 4 degrees to the right of the waning crescent Moon. For the Washington, DC area, Venus will rise in the east-northeast at 3:16 a.m. EDT, and the pair will appear about 28 degrees above the eastern horizon as morning twilight begins at 5:51 a.m..

Sept. 15

On Tuesday morning, Sept. 15, 2020, the bright star Regulus will appear about 6 degrees below the waning crescent Moon. For the Washington, DC area, Regulus will rise in the east-northeast at 4:56 a.m. EDT and morning twilight will begin at 5:52 a.m..

Sept. 17

Thursday, Sept. 17, 2020, at 7 a.m. EDT, will be the new Moon, when the Moon passes between Earth and the Sun and will not be visible from Earth.

The day of, or the day after, the New Moon marks the start of the new month for most lunisolar calendars. The eighth month of the Chinese calendar starts on Thursday, Sept. 17, 2020 (at midnight in China's time zone, which is 12 hours ahead of EDT). In the Islamic calendar the months traditionally start with the first sighting of the waxing crescent Moon after the New Moon, although many Muslim communities now follow the Umm al-Qura Calendar of Saudi Arabia, which uses astronomical calculations to start months in a more predictable way. Using this calendar Safar (the second month of the year) begins at sunset on Thursday, Sept. 17, 2020. Other Islamic calendars may differ, as there are several different religious or national committees and organizations that make independent determinations of when the crescent Moon is first observed and the new month starts. Sundown on Friday, on Sept. 18, 2020, marks the start of Tishrei in the Hebrew calendar. The first and second days of Tishrei are Rosh Hashanah, the head of the year or the Jewish New Year. Rosh Hashanah is the first of a series of holidays, with the tenth day of Tishrei being Yom Kippur and the fifteenth day of Tishrei (close to the full Moon after next) being the start of Sukkot.

Sept. 18

On Friday morning, Sept. 18, 2020, at 9:44 a.m. EDT, the Moon will be at perigee, its closest to the Earth for this orbit.

Sometime around Friday, Sept. 18, 2020 (2020-Sep-18 21:32 UTC with 2 days, 6 hours, 16 minutes uncertainty), a near-Earth object (2014 QJ33), between 159 to 355 feet (48 and 108 meters) across, will pass the Earth at between 2.8 and 23.5 lunar distances (nominally 11.4), traveling at 18,530 miles per hour (8.28 kilometers per second).

On Friday evening, Sept. 18, 2020, if you have a very clear view of the horizon in the west, you might be able to see the planet Mercury appearing to the lower left of the thin, waxing crescent Moon. The bright star Spica will appear farther to the left of Mercury. This may be hard to see without binoculars. The sky will probably not be dark enough to see Mercury and the Moon until the Sun has been down for at least 30 minutes (for the Washington, DC area, after about 7:41 p.m. EDT). Mercury will set about 18 minutes later (at 7:59 p.m.). Evening twilight won't end until 19 minutes after that (at 8:08 p.m.) and the Moon will set 11 minutes after that (at 8:19 p.m.). Please be sure not to use binoculars or a telescope to look for these objects until after the Sun has set!

Sept. 22

Tuesday morning, Sept. 22, 2020, at 9:31 a.m. EDT, will be the autumnal equinox, the astronomical end of summer and start of fall. Somewhere on the equator the Sun will pass exactly overhead.

Tuesday evening, Sept. 22, 2020, if you have a clear view of the horizon in the west-southwest, you might be able to see the bright star Spica appear just below the planet Mercury. You will probably not be able to see them until at least 30 minutes after sunset (after 7:34 p.m. EDT for the Washington, DC area), when Mercury will be only about 3 degrees above the horizon. Spica will set about 16 minutes later (at 7:50 p.m.) and Mercury will set about 4 minutes after Spica (at 7:54 p.m.), so this will be difficult to see and have a narrow window of time in which to look for it.

Also that night, the bright star Antares will appear about 8 degrees to the lower right of the waxing crescent Moon. For the Washington, DC area, evening twilight will end around 8:02 p.m., when the Moon will appear 22 degrees above the southwestern horizon. Antares will set in the southwest before the Moon at about 9:57 p.m.

Sept. 23

On Wednesday evening, Sept. 23, 2020, the Moon will appear half-full as it reaches its first quarter at 9:55 p.m. EDT.

Sept. 24-25

On Thursday evening until after midnight on Friday morning, Sept. 24 to 25, 2020, the bright planet Jupiter will appear about 5 degrees to the upper left of the waxing gibbous Moon, with the planet Saturn appearing farther to the left. From the northern hemisphere they will appear in the south as evening twilight ends. For the Washington, DC area, evening twilight will end at 7:59 p.m. EDT with the Moon 26 degrees above the horizon, and the Moon will set first in the west-southwest on Thursday morning at 12:35 a.m.

Sept. 25-26

On Friday evening into early Saturday morning, Sept. 25 to 26, 2020, the waxing gibbous Moon will have shifted to the east from the night before, appearing about 4 degrees to the lower left of the planet Saturn, with the bright planet Jupiter appearing farther to the right. For the Washington, DC area, the Moon will appear 26 degrees above the horizon in the south-southeast as evening twilight ends at 7:57 p.m. EDT, the Moon will be at its highest for the night (27 degrees above the horizon in the south) at 8:46 p.m., Jupiter will set first in the west-southwest on Saturday morning at 12:48 a.m., Saturn next at 1:25, a.m., and the Moon last at 1:35 a.m.

Oct. 1

Thursday, Oct. 1, 2020, will be when the planet Mercury reaches its greatest angular separation from the Sun as seen from Earth for this apparition (called greatest elongation), appearing half-lit through a large enough telescope. Because the angle of the line between the Sun and Mercury and the horizon changes with the seasons, the date when Mercury and the Sun appear farthest apart as seen from Earth is not the same as when Mercury will appear highest above the horizon in the west-southwest 30 minutes after sunset (an approximation of when it might be dark enough to see Mercury), which occurred earlier in September.

Sometime in late September or early October 2020 (2020-Oct-01 14:59 UTC with 6 days, 17 hours, 18 minutes uncertainty), a near-Earth object (2001 GP2), between 36 to 81 feet (11 and 25 meters) across, will pass the Earth at between 0.4 and 14.3 lunar distances (nominally 6.1), traveling at 4,950 miles per hour (2.21 kilometers per second).

As mentioned above, the full Moon after next will be on Thursday evening, Oct. 1, 2020. This will be the Harvest Moon, the Chinese Mid-Autumn Festival, and one of the smallest full Moons of the year (the opposite of a supermoon, sometimes called a micro full Moon).