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 Kingdom of Orion

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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 January 2022, pictures a landscape from Navarra, a province in the north of Spain with ruins from old civilizations in the foreground. Above that, we see a partially cloudy and starry sky with the most prominent stars belonging to the star pattern Orion. Composed of many bright stars with several interesting deep sky objects within its boundaries, Orion is one of the 88 officially recognised IAU constellations. It originates from Greek mythology where the hero Orion is the son of the sea god Poseidon. Orion is characterised as a giant hunter lurking just before he attacks an animal (it is unclear which animal he attacks, but, in the original Babylonian version of the Gilgamesh saga, it is the Bull of Heaven depicted as the constellation Taurus). The modern planetarium interpretation depicts him as a Roman warrior raising up his shield, but the two accompanying dogs, represented by the constellations of Canis Major and Canis Minor, are reminiscent of the Greek hunter. Located at the celestial equator, the star pattern is visible all over the world and is interpreted differently in various mythologies, for example as three fishermen at a campfire in parts of Australia, as a butterfly in some parts of Africa, and as a stairway for the souls of ancestors in parts of South America. As Spain belonged to the Roman empire, the original constellations from earlier times are not known. There are some cave paintings on the Iberian peninsula that could possibly have astronomical references. However, there is uncertainty as to whether these painted figures on rocks depict star patterns. Orion is best visible from November to January. Its most recognisable feature is the “belt”, an asterism composed of three bright, aligned stars (Alnitak, Alnilam and Mintaka), also recognised by different cultures. Just below this belt is the Orion Nebula, a famous and widely studied star-forming region located about 1500 light-years from Earth. The constellation's brightest stars are Rigel — a blue supergiant which is one of the brightest stars in the sky — and Betelgeuse — a massive red supergiant. The former serves as the left foot, and the latter as the right shoulder of the hunter. While Rigel is in the middle of its life, Betelgeuse is expected to explode within the next few tens of thousands of years. The Orionids, a meteor shower with typical rates of dozens of meteors per hour, whose parent body is Halley’s Comet, can be seen every year in the area of Orion, next to the border with the constellation of Gemini during the month of October.
Credit: Carlos Zudaire/IAU OAE

Glossary Terms: Constellation , Red Supergiant , 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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Orion Rises Over Mount Etna

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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 February 2021, this image is a composite of an astronomy picture in the background and Mount Etna, the famous volcano in Sicily, Italy, in the foreground. Prominently, we see the red hydrogen clouds in space in the area of Orion. Barnard’s Loop is the gigantic bow with the Great Orion Nebula and the Horsehead Nebula in its centre. The deeper-coloured Horse Head is below the southernmost stars in Orion’s Belt, which is the line of white stars above the red nebula. Clearly visible is also the division between the Small and the Great Orion Nebula, the circular and the trapezium-shaped structure in light pink within which one of the nearest star-forming regions is located. The nebula is only a bit more than a thousand light-years away. In the middle-left, close to the edge of the image, the small red structure is the Monkey Head Nebula still in the constellation Orion. It hosts a young star cluster and the deep red colour of this hydrogen cloud indicates its potential to build new stars in the future if the material is compressed again. All these reddish objects are strongly processed in this image, as they are not visible to the unaided eye. Still, this image provides an interesting feature; the red supergiant star Betelgeuse lies in the middle of the image and it seems to be directly above the active volcano Mount Etna. At the foot of this volcano is an ancient settlement, the city of Catania. We consider both Betelgeuse and Mount Etna somehow dangerous — but which of them will erupt first? Ok, we know that Etna occasionally erupts. Normally it exhibits only small eruptions, but the bigger ones happen every few centuries. We also know that Betelgeuse as a giant star will become a supernova in the future. Astronomers call the timescale for the potential supernova short, implying that it will be only 10 000 or maybe 100 000 years until this star explodes. This is “soon” for astronomers, meaning that on Earth, two to four precession cycles will pass by (with the consequence that the Sahara will turn green and dry again two to four times), continental drift will take Africa further north and cause the Alps to grow in height, the Niagara falls in America will wash the rock completely away and only after all this (and much more) happening on Earth will Betelgeuse explode as a supernova. Mount Etna is much more dangerous for the people in Sicily, and Catania in particular, because it will erupt sooner.
Credit: Dario Giannobile/IAU OAE

Glossary Terms: Constellation , Interstellar Medium , 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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Luminous Salar de Uyuni

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Created for the OAE

Caption: Winner in the 2022 IAU OAE Astrophotography Contest, category Still images of celestial patterns.   This black and white image taken in February 2017 in Uyuni Salt Flat of southwest Bolivia, the biggest salt flat in the world, shows one of the most recognisable constellations, Orion the hunter, and the open star cluster of the Hyades directly above the clouds at the horizon. Various cultures have different stories associated with Orion. The Aymara in this area of the world (Bolivia and Northern Chile) consider Orion’s Belt to be a Sky Bridge (chacka cilitu) or a Stairway made out of dough. This stairway is rather obvious in this picture. It appears as if the stars in the sky are scattered like grains of salt on the ground — an amazing composition. For the Aymara, who were Christianised by the Spanish conquistadores, Orion and the Stairway are connected to the November festivals of the dead ancestors and the souls. In contrast to the original Christian culture, for these people in the southern hemisphere these festivals mark the beginning of summer, not the beginning of winter. While in the north, the “ghosts” of the ancestors are represented by the foggy weather in November, the Aymara greet the ancestors with flowers. This photograph in the dry salt flat, in contrast, seems to show the unlivable loneliness where the photographer meets the souls of the deceased. The Yolnu people of Arnhem Land in Australia’s Northern Territory have a rich culturally significant story associated with Orion that carries a lesson. It tells of the three brothers of the Kingfish clan and their canoe Djulpan. Owing to their lack of patience, the brothers ate the sacred Kingfish, angering the Sun woman Walu who created a waterspout that sent them into the sky. Looking at the constellation Orion, the three stars in Orion’s belt represent the three brothers, Orion’s sword is the fishing line, and the two dimmer stars Bellatrix and Saiph form the two ends of the canoe Djulpan.
Credit: Stephanie Ye Ziyi/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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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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