Galaxy Arm

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Created for the OAE

Caption: Honourable mention in the 2022 IAU OAE Astrophotography Contest, category Still images of celestial patterns.   Taken from the south of Iraq in January 2022, this image shows a clear sky over one of the many ancient monuments in the region which looks like a Babylonian ziggurat. The Sumerians had invented these mountain-like buildings even before the invention of script; the earliest ziggurats appear around 4000 years before the common era. They look like the frustum of a pyramid and in Babylonian times often had temples on top. Next to the stairs of the ziggurat are the constellations of the southernmost part of the Zodiac, also invented in Babylon. Today, we call them Capricorn (left, with a planet in it) and Sagittarius, whose brightest stars form the asterism of the Teapot. For the Babylonians, Sagittarius was the god Pabilsang, the city god of Larak and a god of agriculture and war. He was also the husband of the mighty goddess of medicine, Gula, and his iconography is a hybrid creature holding a bow and arrow: a male human torso and head attached to the body of a horse with four legs, two gigantic wings and two tails — a horse tail and a scorpion tail. Such a creature did not exist in Greek mythology, so the Greeks reduced it to something they knew, a centaur holding a bow and arrow. This picture still did not make sense in Greek culture because centaurs were considered wild and cruel, and not intelligent enough to use a bow and arrow. Therefore, there was another Greek figure that existed simultaneously: a man with hooves instead of feet at the ends of his legs, a satyr, but this figure vanished in Roman times.  Capricornus is one of the most stable foreign creatures in the Zodiac and has been unchanged over millennia. It is depicted as a hybrid creature with the front part of a goat and the back part of a fish. This so-called Goat-Fish constellation has been recognised since the earliest writings of astronomy in Babylon. In Babylonian religion it is a good-natured, benevolent demon that protects humans, supports all healing processes and accompanies the god of wisdom and witchcraft. The Greeks simply adopted it and invented a saga for it. In Roman times, it became tremendously famous because emperor Augustus of Rome used it as his personal symbol, also imprinting it on coins and other political propaganda tools. In Sagittarius, there is also the bright bulge of the Milky Way. That this is hardly visible in this photograph is a result of modern civilization; the huge number of artificial lights that we use on Earth also illuminates the night sky and makes it impossible to see the Milky Way in areas where humans live.
Credit: Ruqayah Mohammed/IAU OAE

Glossary Terms: Capricornus , Sagittarius
Categories: Naked Eye Astronomy

License: Creative Commons Attribution 4.0 International (CC BY 4.0) Creative Commons Attribution 4.0 International (CC BY 4.0) icons

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Watchtower and Paddy Fields Under the Starry Sky

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Created for the OAE

Caption: Winner in the 2022 IAU OAE Astrophotography Contest, category Still images of celestial patterns.   This image, taken in April 2022, shows the sky over a plantation field around a century-old watchtower guarding a village in the province of Guangdong, China. Throughout the ages, the sky has been used as a tool for navigation and also as a calendar. By watching the apparent movement of the stars, it is possible to follow the passing of time, thereby understanding the change of the seasons which in turn helps to plan out the best timings of agricultural work. The most prominent constellations in this image are Orion and Canis Major, the Great Dog. Commonly associated with a giant hunter in Greek mythology, Orion is followed by his hound in the shape of the constellation Canis Major. In China, the seven bright stars of the constellation Orion are paradoxically called Three Stars (Shen) and this is one of the 28 Lunar Mansions. The Babylonian pre-zodiac, the so-called “Path of the Moon”, had 17 constellations and included Orion (therein named “True Shepherd of the Heavens”). This is not really surprising because, even in the system of the 88 modern constellations, the Moon sometimes stands in the constellation Orion. The modern constellation boundaries were defined in the 1920s in such a way that the area of Orion ends a half degree south of the ecliptic, in order to avoid the Sun entering it. Still, the Moon and the planets do occasionally. Therefore, Orion is part of the Zodiac (a stripe 5 to 10 degrees around the ecliptic), part of the path of the Moon and, of course, also used by many cultural calendars all over the world. Sirius, the bright star in the left half of the photograph, is the brightest star in the night sky, and has been used by many indigenous cultures to determine their calendars; the Egyptians awaited the Nile flood with Sirius’s heliacal rise, while the Romans connected its reappearance after its invisibility in daylight with the hottest summer time. In Old China, Sirius was considered a single-star asterism called The Wolf. The adjacent area was called The Market for Soldiers and the area in the southern part of Canis Major was imagined as the Bow with an Arrow. The reddish bright star in the top right corner is Betelgeuse, a red supergiant and one of the largest stars that can be seen with the naked eye. Orion’s Great Nebula below Orion’s Belt should be mentioned, but also the fainter huge red arc that is called Barnard’s Loop is clearly shown in this photograph. This galactic nebula and the circular red nebula around Orion’s not-so-bright head are both parts of star-forming regions, while the red nebula to the upper left of Orion is the Rosette Nebula in the unrecognisable constellation of Monoceros.
Credit: Likai Lin/IAU OAE

Glossary Terms: Color , Constellation , Red Supergiant , Star , Orion
Categories: Naked Eye Astronomy , Stars

License: Creative Commons Attribution 4.0 International (CC BY 4.0) Creative Commons Attribution 4.0 International (CC BY 4.0) icons

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Romanian Orion

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Created for the OAE

Caption: Winner in the 2022 IAU OAE Astrophotography Contest, category Still images of celestial patterns.   Taken in Romania in August 2012, this image shows two of the most recognisable constellations in the sky, Orion and Taurus. Orion, the Hunter, is found near the horizon. The most prominent star visible in this image is Betelgeuse, while the asterism of Orion’s belt is formed by three aligned bright stars. Just above Orion we can find Taurus, one of the constellations of the Zodiac. As the Zodiac is inherited from Babylon, The Bull of Heaven represents a mighty but dangerous creature that was defeated by King Gilgamesh and his friend Enkidu. They cut the Bull in half and sacrificed the animal to the gods in order to protect their people. Taurus is also home to the star cluster Pleiades, also known as the Seven Sisters. Two planets are visible: Venus, the bright spot near the fence, and Jupiter, the bright spot at the top, next to the Bull’s face. Different cultures have included the stars of these constellations in their own mythology. The Romanians, for instance, after Christianisation identified four other constellations using some of the stars of Orion and others surrounding it. One such constellation is called Trisfetitele (the Three Saints), which is associated with the three stars comprising Orion's Belt, representing the Three Hierarchs Basil, Gregory and John. This same asterism is also called Three Wise Men, Kings from the East or just Three Kings — all of these names being rooted in the Christian religion. The agricultural calendar, in contrast, led farmers to define two other constellations, the Little Plough and the Sickle. Both are seen in the southern half of the Orion rectangle; the Little Plough is drawn by connecting the southern quadrilateral with Orion’s left shoulder, and the Sickle is formed by connecting Orion’s left foot (Rigel) with the belt stars, forming an arch and completing the form of a hoe. In the cultural calendar, these constellations were used to announce the harvest of wheat/grain. Finally, the fourth Romanian constellation is the Great Auger, where Orion’s belt represents the handle of the auger, and Betelgeuse is the tip, facing towards Pollux in Gemini. This constellation is associated with treasure, as Romanian peasants believe that the Auger points to the treasure when they approach the end of the world. Most of the official star names in Orion are Arabic; Mintaka (meaning “belt”) is at the waist; Alnitak (meaning “girdle”) and Alnilam (meaning “string”) are at the belt; and Rigel (meaning foot) is at the left foot. The star on the left shoulder is named Bellatrix, the Latin term for a female warrior. The star at the right leg is called Saiph, for the sword or sabre of the Arabic Orion.
Credit: Alex Conu/IAU OAE

Glossary Terms: Constellation , Gemini , Jupiter , Taurus , Venus , Asterism , Orion , Pleiades
Categories: Naked Eye Astronomy

License: Creative Commons Attribution 4.0 International (CC BY 4.0) Creative Commons Attribution 4.0 International (CC BY 4.0) icons

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The Hunter in the Forest

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Created for the OAE

Caption: Honourable mention in the 2022 IAU OAE Astrophotography Contest, category Still images of celestial patterns.   Taken in December 2016, this image shows a clear and starry sky over the Masaya Volcano National Park in Nicaragua. The constellation Orion is the most prominent pattern in this image. Orion is associated with a great hunter according to Greek culture, and is seen here right in the middle. The reddish star in the centre is Betelgeuse, the second-brightest in this constellation and one of the brightest in the night sky. Above and to the right of Betelgeuse we find Bellatrix, another bright star, forming the right shoulder of the hunter. Extending a line from Bellatrix to the right, we find a crookedly aligned group of faint stars comprising Orion’s bow. We can also easily see a group of three aligned bright stars forming the belt of the hunter, an asterism recognised by many different cultures. Just below his belt we can see the silverish glittering that was interpreted as the metal of Orion’s sword or knife by the Greco-Roman tradition. It was alternatively interpreted as a fish roasted on a campfire by some cultures in Australia. In its centre, with binoculars we can see the Small and the Great Orion Nebula, together forming a giant cloud of dust and gas where new stars are being formed. To the lower-left of the silverish compound of tiny stars and nebulae, there is a bright star called Saiph, the Arabic term for “Sword” or “Sabre” because it was considered the tip of a huge knife with a curved upper part. To the right of this, there is the bright bluish star Rigel, an Arabic term which designates it as The Foot of Orion. Orion’s Belt points up towards Aldebaran at the edge of the photograph and down towards Sirius among the branches of the trees; it is the brightest star in the night sky and is located in the constellation Canis Major. Earth’s atmosphere makes the bright Sirius twinkle in all colours. Seen from space it is pure white, but as its light travels through the air, it is scattered and distorted by the molecules. Therefore, the star appears to change colour like a diamond. A line connecting the two shoulders of Orion points to another bright star in the lower-left corner of the photograph. This is Procyon, located in the constellation Canis Minor. Procyon has been used by the ancient Babylonians to indicate the heliacal rise of Cancer (whose stars are faint, and invisible in twilight) and to predict the rising of Sirius. Thus, for a very long time in ancient history Procyon was considered a single-star asterism. Perhaps only in Roman times were more stars used to create a constellation in this area of the sky, although this constellation has never been clearly recognisable.
Credit: René Antonio Urroz Álvarez/IAU OAE

Glossary Terms: Constellation , Orion
Categories: Naked Eye Astronomy , Stars

License: Creative Commons Attribution 4.0 International (CC BY 4.0) Creative Commons Attribution 4.0 International (CC BY 4.0) icons

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Forgoing the Summer Triangle as it sets in the early winter evening

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Created for the OAE

Caption: Winner in the 2022 IAU OAE Astrophotography Contest, category Still images of celestial patterns.   This image was taken from Nagano, Japan, in December 2018, and shows three prominent constellations: Aquila (towards the lower-left of the image), Cygnus (in the upper part of the image) and Lyra (bottom-right). The brightest stars within these constellations (Altair, Deneb and Vega) form the three vertices of the asterism known as the Summer Triangle. The star Altair is the brightest star towards the bottom-left of the image, Deneb is the brightest star towards the top-right of the image, and Vega is the brightest star towards the bottom-right of the image. In Asian cultures the stars Vega and Altair represent a love story between the weaver girl and the herdsman, who are separated by the faint band of the Milky Way, but in July are allowed to cross the heavenly river (the Milky Way) to be together. The Boorong people of Northeast Victoria, Australia, associate the reappearance of Vega — after its yearly disappearance from view — with the time when the Mallee fowls build nests. The Boorong also associate their indigenous constellation Neilloan with the goddess Mallee-hen (Vega), mother of Totyarguil (Altair), the hero who created the Murray River. In Wardaman traditions, the star Vega acts as a gateway to the Milky Way for spirits of the deceased. The star name Altair is abbreviated from the Arabic “Al-Nasr Al-Ta’ir” (meaning “The Flying Eagle”) proving that the constellation of the Eagle (Aquila) is one of the most stable ones in history. Originating from the Babylonian epoch (carrying a king towards the sky), it was taken over by the Greeks, Romans, and Arabs. The star name Deneb comes from the Arabic word “dhanab”, meaning “tail”, and refers to the Greek constellation of The Bird that is interpreted in the Roman tradition as a Swan (Cygnus), and as a Hen in the Arabic world. The third star name, Vega, comes from the Arabic “Al-Nasr Al-Waqi”, meaning “The Swooping Eagle'', because the indigenous (pre-Islamic) Arabic culture had a second eagle in the area of the Greek constellation Lyra. In the Early Modern Age, some Christian astronomers, inspired by the Arabic tradition, depicted this constellation as an eagle or vulture holding a lyre. The image also shows a range of other constellations, including Delphinus, Sagitta, and Vulpecula. According to Greek mythology, Sagitta, The Arrow, carried the god of light and the goddess of fertility. In winter they set in the evening but in spring they rise again in the east, and are present for longer and longer in order to make the land fruitful and agriculture successful.
Credit: Kouij Ohnishi/IAU OAO

Glossary Terms: Asterism
Categories: Naked Eye Astronomy

License: Creative Commons Attribution 4.0 International (CC BY 4.0) Creative Commons Attribution 4.0 International (CC BY 4.0) icons

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