Moon watchers get an extra treat this month with a blue moon.
A blue moon is usually defined as the third full moon in a season that has four full moons, although the term is sometimes used to refer to the second full moon in a month.
The blue moon will rise in the night August 30 at 9:35 p.m. ESTAccording to the US Naval Observatory, it will be a “blue moon” and a “supermoon” — not only is it the second full moon in a month, but the moon is as close to Earth as it is and therefore appears slightly larger and lighter than usual. On the same day, the moon will approach Saturn.
Related: Blue Moon: What is it and when is it next?
A blue moon occurs approximately every two and a half years. “Blue Moon” like “Supermoon” isn’t really an astronomical term. A blue moon indicates one of two things: a second blue moon in a month (called a calendar blue moon) or a fourth full moon in a season (a seasonal blue moon). A season is the period between the solstices and the equinoxes (for example, the summer season begins on June 21—the summer solstice—and ends on September 23, the autumnal equinox). Normally one would expect three full moons in one season, but sometimes we see four full moons. In this case, there are still three full moons between June 21st and September 23rd, but we get two full moons in August because the month has 31 days. So the August Blue Moon is calendar, not seasonal.
A full moon occurs when the Moon is on the opposite side of the Earth from the Sun, a position it reaches about every 29.5 days. Technically, the celestial meridian is 180 degrees from the sun in the sky. The Moon’s orbit is tilted about five degrees from the plane of Earth’s orbit, so even though the Moon is “behind” the Earth, it is not in the Earth’s shadow every time it makes a circle of our planet. When it passes through the Earth’s shadow, we see a lunar eclipse, but this time it will not happen. The timing of the lunar phases depends on an individual’s time zone, as it is based on the Moon’s position relative to the Earth rather than its location on Earth.
Supermoons, meanwhile, indicate when the full moon coincides with perigee, which is the point in the moon’s orbit when it is closest to Earth. At those times, the Moon appears slightly larger and therefore brighter, although it is not usually noticeable to the casual observer. This happens because the Moon’s orbit is not a perfect circle; While the average distance to the moon is 238,855 miles (384,400 kilometers), this time the moon will be 221,942 miles (357,181 km). We call this a supermoon, but in fact the full moon can be very close at any time — it’s most noticeable when it coincides with the full phase. The moon will reach perihelion at 11:55 a.m. ESTaccording to NASA, and appears about 7 percent larger than usual.
In New York City, the Moon, in the constellation Aquarius, will rise on the evening of August 30 at 7:44 PM and set the next morning at 6:47 AM, and Saturn will appear above and to the right of the Moon as it rises. The moon’s closest approach to Saturn will occur at 2:07 p.m. east, according to at-the-sky-org, so it will not be visible from the Western Hemisphere. However, observers in Central Europe are well placed to capture the moment when the Moon and Saturn are closest together — they share the same celestial longitude — and when they come so close. In Warsaw, for example, the moon and Saturn rise around 7:37 p.m. local time and conjunction occurs at 8:07 p.m. At 9:43 p.m. local time, the moon will pass just 2 degrees from Saturn, with the moon appearing below the planet. directly.
As one moves east, the conjunction occurs later in the evening and the Moon and Saturn are higher in the sky. From Istanbul, the moon and Saturn rise around 7:35 p.m., and close approach occurs at 10:43 p.m. The moon will appear more directly below Saturn than New York. In New Delhi, both approaching and approaching happen after midnight. Approach is at 1:13 a.m. local time on August 31, about an hour after the moon reached its highest point in the sky; The Moon will be directly below and slightly to the left of Saturn, at 44 degrees high in the south.
In the Southern Hemisphere, the conjunction will look different — Saturn will appear below the moon, as the sky looks “upside down” from there. In Melbourne, Australia, for example, approach occurs at 5:43 a.m. local time on August 31, and the pair will be low in the west, with Saturn visible below and to the right of the moon. Both are set by 6:50 a.m. local time.
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Along with Saturn, which will track the Moon closely (even when not in conjunction, it will spend the night a few degrees from the Moon), Jupiter rises on August 30 in 10:16 p.m. local time in New York. In the constellation of Eris, the planet is distinguished because of its brightness relative to the other stars in that region of the sky.
Mars will be barely visible in the evening; On August 30th in New York the sun sets at 7:31 PM ET. Mars sets just one hour later, at 8:32 p.m.; It is possible to see it if one is lucky and has a clear sky and an unobstructed horizon, but half an hour after sunset the planet is only 6 degrees above the horizon.
Venus will be the “morning star” — the planet will rise on the morning of August 31 at 4:33 a.m. east and will rise about 10 degrees by 5:30 a.m., when it starts to light up in the sky. Venus is so bright that it is conspicuous against the sky and among the other stars, and in fact remains visible even after the stars have begun to fade; It is often the last celestial body (besides the moon) that people can see before sunrise.
The constellations visible at the end of August are still very much those of the summer; At around 9 pm in mid-northern latitudes, the Summer Triangle is still visible near the zenith; The highest of the three brightest stars it marks is Vega, if one were facing south of Deneb it would appear to the left and a little closer to the horizon, while Altair is the southernmost – the Summer Triangle looks like a large right triangle with Vega at a 90-degree angle and the hypotenuse connecting Deneb and Altair. Like the Big Dipper, one can use it to find their way around; The line between Vega and Altair almost always points south in the Northern Hemisphere.
Scorpio and Sagittarius will be visible to the south; The latter is about as high in the sky as it gets. Antares is a reddish star that is Antares, Scorpius. Just above Scorpio is an area of the sky containing a group of five stars that looks like a long, narrow box surmounted by a triangle, like an A-frame house. This is the body of Ophiuchus, the serpent-bearer. The constellation is difficult to see from city sites; Its stars are relatively dim compared to the planets Scorpius or the visible planets.
Turning west (to the left) and looking toward the moon, one can see the autumnal constellations rising; To the moon’s left is Pegasus, the mythical winged horse that can be seen by looking for the “great square” which will appear to stand on one corner, with that corner pointing directly at the eastern horizon. The star to the left of the Great Square is the head of Andromeda, which, according to legend, was being sacrificed to Leviathan (Cetus, which rises later in the night). Andromeda is made up of two curved lines of stars that look like bananas.
As one continues north, one can see above and to the left of Andromeda a “W” of stars that is, the Queen, Cassiopeia, the mother of Andromeda, and if one looks to the left extends to Polaris, the North Star. Almost opposite Cassiopeia is the Big Dipper, part Ursa Major, the Great Bear. The dipper will appear with the “bowl” facing up and to the right. If one is in a dark sky location, it is also possible to see Draco the Dragon, which is a cluster of stars that coil between the Big Dipper and the Little Dipper (Ursa Minor, Little Dipper).
From mid-south latitudes, Vega will be roughly north at around 9 p.m., and from Santiago, Chile, Cape Town, or Melbourne it will be about 17 degrees above the horizon. Cygnus, the swan, containing Deneb, will be to the right (east) and Altair will be at about 45 degrees. In the Southern Hemisphere, the sky is reversed, so the Summer Triangle points further away from the horizon. If one follows the line from Vega to Altair eastward and passes the Moon and Saturn (Saturn will be above the Moon) one can see Fomalhaut, the brightest star in Piscis Austrinus, the southern fish. Further to the right (now heading southeast) one can observe the fainter star cluster Grus, The Crane; It is easiest to look for a vertical line of three stars which is the body of the bird. In the southeast, 20° to 23° high, Achernar is the brightest star in the Eridanus River, which begins near the foot of Orion in the Northern Hemisphere.
Turning south, toward the south celestial pole (there is no Polaris equivalent there), one will see brighter stars to the right, in the southwest. On its side lies the Southern Cross, Crux, a small, bright cluster that also has the distinction of being the smallest of the 88 modern constellations. Above Crux are two bright stars, the highest being Rigil Kentaurus, also known as Alpha Centauri. The one below it is Hadar, or Beta Centauri.
Blue Moon names
The indigenous peoples of North America had a number of different associations and names for the month of August and the full moon; The Old Farmer’s Almanac says August’s full moon is the sturgeon moon, as that’s when fish are plentiful. However, the Old Farmer’s Almanac names derive from a mixture of European and Native American traditions in the areas where the English, French, and Dutch established their colonies, largely in the northeastern part of the continent.
This does not reflect what the indigenous people of each part of the Americas believed, as the traditions that indigenous peoples developed depended very much on the local environment and history; For example in the Pacific Northwest, the Tlingit refer to August (the eighth lunar month) as Sha Ha Ye Dis, which means “ripe berries on the mountain” and the ninth moon (which the new moon will see on August 30th) is Dís Yádi, or Small animal moon. Even in the Northeast there were differences: the Abenaki (according to the English fur trader William Pynchon, writing in 1645) were called moons from July to August. Awkesos Law Matter Which means “when the squash is ripe” and it was the ninth full moon micheeneeekesos or “When the Ind(ian) corne is edible”.
In England, the name derived from the Anglo-Saxon for the eighth moon (which usually occurs in August) is fruit moon. The eighth lunar month according to St. Bede (writes in his book De Temporium Rationeor “calculation of time” in 725 AD) indicates that the “pagans” – people not yet Christianized living in what is now the British Isles – called the eighth lunar moon Weodmonath, or “the month of vegetation” and in Old German the August moon refers to Aran-manod, or “the month of harvest.”
In the Southern Hemisphere, September is springtime, and with the days getting warmer, it is not surprising that the New Zealand Maori describe the lunar months from August to September as mahuru: “The land has now gained warmth, and so have the plants and trees,” according to the Encyclopedia of New Zealand.
Editor’s note: If you got a great photo of the blue moon in August 2023 and would like to share it with Space.com readers, send your photo(s), comments, name, and location to [email protected].
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