When viewing any portion of the sky, changes may be detected that initially cannot be categorized or understood. These are often designated as an entity until better described. This is entity astronomy.
While it is arguable that any entities are controlling the sky, entities may be assigned as a first approximation in the theory of cause and effect. An entity that produces comet-like objects may exist.
The Sun moves across the sky during the day time only. An entity or two may be responsible for this.
A storm cloud blocks the day time sky while releasing rain. Perhaps a different entity may be assigned for each of these effects, or one for all. Many people like gravity as an entity. Is gravity the entity or force behind the falling of the rain or the releasing of the rain?
The Moon also crosses the sky occasionally sometimes in the daylight other times at night. The Moon doesn't always reflect uniformly during its travels. A shadow often blocks some of the reflection. Which entity is the cause for this, or is it an object, or perhaps a source of shadow? Is there a shadow radiation?
Although the entity Thor (also called Jupiter in other cultures) is an entity assigned to throwing lightning bolts, is Thor throwing the lightning bolts over Bucharest, Romania.
Theoretical astronomy tries to assess which entities may be responsible for controlling the sky away from a pleasant fair weather day. And, in turn seeks to explore those that may allow us to control the sky for a few more fair weather days.
Theoretical entity astronomy
- 1.a: an "independent, separate, or self-contained [astronomical] existence",
- 1.b: "the [astronomical] existence of a [person, place, or] thing as contrasted with its attributes", or
- 2. "some [astronomical] thing that has separate and distinct existence and objective or conceptual reality",
is called an astronomical entity.
This article and each of the articles focusing on any entity from astronomy is itself an astronomical entity. In terms of meaning and generalness: 'being' > 'body' > 'something' or 'thing' > 'entity'. But, for information processing, astronomical 'being', 'body', 'something' or 'thing' are also astronomical entities.
Each section in the astronomy lecture mentions or shows images of astronomical entities:
- Barringer Meteor Crater,
- Earth (as a planet),
- Aurora Borealis,
- Astronomical objects,
- Astronomical sources,
- Astronomers and Observers,
- Calendars, Star charts, Constellations,
- Telescopes and other technology,
- Physical astronomy and Astrophysics,
- Astrodesy, Astrognosy, and Astrometry,
- dominant groups, orbits and logical laws,
- Chemicals, Materials, and ions, etc.
At the right beneath a portrait of Johannes Kepler is a copy of the title page of Johannes Kepler's Rudolphine Tables (1627). It is regarded as the most accurate and comprehensive star catalogue and planetary tables published up until that time. It contained the positions of over 1000 stars and directions for locating the planets within our solar system. Kepler finished the work in 1623 and dedicated it to his patron, the Emperor Rudolf II, but actually published it in 1627. The table's findings support Kepler's laws and the theory of a heliocentric astronomy.
"The Bodhisattva Avalokiteshvara is one of two Bodhisattvas (along with the Tara) that come from the 'Western Pure Land' of the Amitabha Buddha. Avalokiteshvara is the Bodhisattva of Compassion, and is said to have taken his vows to protect the people of Tibet, the 'Land of the Snows'. He is therefore often considered the protector of the mountain kingdom of Tibet. This painting on canvas shows Avalokitesvara with 11 faces. In Tibetan Buddhism this is one of the forms of Avalokitesvara and is known as Ekadasamukha."
"In Egypt, blue was associated with the sky and with divinity. The Egyptian god Amun could make his skin blue so that he could fly, invisible, across the sky. Blue could also protect against evil; many people around the Mediterranean still wear a blue amulet, representing the eye of God, to protect them from misfortune."
"Many of the gods [in Hinduism] are depicted as having blue-coloured skin, particularly those associated with Vishnu, who is said to be the Preserver of the world and thus intimately connected to water. Krishna and Ram, Vishnu's avatars, are usually blue. Shiva, the Destroyer, is also depicted in light blue tones and is called neela kantha, or blue-throated, for having swallowed poison in an attempt to turn the tide of a battle between the gods and demons in the gods' favour."
Rama imaged at left is the Daśāvatāra seventh avatar of the god Vishnu in Hinduism, and a king of Ayodhya in Hindu scriptures. In a few Rama-centric sects, Rama is considered the Supreme Being, rather than an avatar. Rama was born in Suryavansha (Ikshvaku Vansham) later known as Raghuvansha after king Raghu. When depicted with his brother Lakshman and consort Sita, with Hanuman kneeling in a state of prayer, this form is called Ram Parivar, and is the typical fixture depicting Rama in Hindu mandirs, or temples.  The Hindi word parivar translates as "family." 
On the lower right is an ancient work which is a painting after, according "to Mahayana Buddhism, Shakyamuni turned himself into a deep blue Buddha, giving off healing rays of light, and taught a gathering of men and gods the science of medicine. In many Buddhist countries the Medicine Buddha, is the patron of medicine and healing, and the special god of physician."
The third image down on the left is an ancient work portraying Paramasukha Cakrasamvara Yab-Yum Luipa Mandala.
"Here in this painting on linen, the male and female figures of Samvara avd Vajravarahi actually indicate Compassion and Wisdom. Buddhahood, or enlightenment, is often shown as the perfect union of compassion and wisdom. This whole is often expressed visually by the sexual union of a male figure and a female figure, or Yab-Yum, which is sometimes translated as Mother-Father. By meditating on this image, and imagining themselves to be both figures in the image, Tantric Buddhists gain an insight into the deeper aspects of reality."
Huitzilopochtli at second right was the patron god of the Mexica tribe. Originally he was of little importance to the Nahuas, but after the rise of the Aztecs, Tlacaelel reformed their religion and put Huitzilopochtli at the same level as Quetzalcoatl, Tlaloc, and Tezcatlipoca, making him a solar god.
Over the South presides the Blue Tezcatlipoca, Huitzilopochtli, the god of war.
The Vajra mudrā "thunder gesture" exhibited by the cyan colored statue on the left is the gesture of knowledge.
At left is Rahu. Rahu is God of the Ascending / North lunar node. Rahu is the head of the demonic snake that swallows the sun or the moon causing eclipses, according to Hindu scriptures. He is depicted in art as a dragon with no body riding a chariot drawn by eight black horses. He is a Tamas Asura who does his best to plunge any area of one's life he controls into chaos.
On the right is the green god Tara.
"This is one of the finest example of Tangut art. This is not a painting but the figures have been woven in kesi technique (“incised silk,”a particular type of Chinese tapestry) like a carpet. This image can be attributed to the Tibetan school of the Tangut tradition. Tara's name means 'the one who saves', and her desire to save is said to be stronger than a mother's love for her children. In some myths Tara was born from the compassionate tears of Avalokiteshvara in the Pure Land (a concept very similar to that of heaven.) Tara is is the best example of the Bodhisattva as goddess, and represents the miraculous activities of all Buddhas by helping beings overcome difficulties on the path to enlightenment. The goddess is shown here seated on a lotus; above her are the five Transcendent Buddhas and flanking her two Taras: the benevolent Aśokakāntā, with a yellow body, and the blue angry Ekajatā. At the stem of the lotus are genuflecting nagas; above and below the composition are additional miniature figures of heavenly musicians and dancers."
Krishna is the Daśāvatāra eighth incarnation of Lord Vishnu in Hinduism. Worship of the deity Krishna, either in the form of Vasudeva, Bala Krishna or Gopala can be traced to as early as 4th century BC. He is often shown wearing a yellow silk dhoti and a peacock feather crown. ... The Harivamsa describes intricate relationships between Krishna Vasudeva, Sankarsana, Pradyumna and Aniruddha that would later form a Vaishnava concept of primary quadrupled expansion, or avatar.
"The Hindu Atharva Veda speaks of the "four heavenly directions, having the wind as lord, upon which the sun looks out."63 This, of course, can only be the central sun, who is Brahma, a god of four faces. The myths also attribute four faces to Shiva.64 The central sun Prajapati takes the form of the four-eyed, four-faced, and four-armed Vivvakarman, the "all maker".65 Agni, too, faces "in all directions,"66 as does Krishna.67 ... There can no longer be any doubt that the four-eyed or four-faced god is Saturn, for the sun-planet appears in Babylonian myth as Ea (Sumerian Enki)-a god of four eyes that "behold all things."73"
"This [image on the right] is one of the most interesting paintings done with mineral colours on silk. It combines, Indian and Greek ideas about astronomy. Buddha is shown seated with 10 planets that include Indian imaginary planets of 'Rahu' and 'Ketu.' The Sun and the Moon are show as Emperor and Empress. All 12 signs of Zodiac of Greek origin such as Aries, Taurus, Gemini are shown in circles in two rows towards top. In between these two rows there are images in 28 circles in all. These are the Indian constellations along the Ecliptic, known as “Nakshatras.” This painting is perhaps the best example of mixing of ideas of Indian, Greek and Chinese origin that happened all the time along the silk road."
"Among the northern Egyptian constellations, there is a magnificent one, occasionally named Isis-Djamet, taking the form of a huge female hippopotamus with a crocodile tail or an entire crocodile on her back [...]. This constellation could be the one that appears in the Ramesside star charts with the name [...], the “Hippopotamus” or Reret. In most representations, she holds two mooring posts in the form of a dagger or a small crocodile. This huge hippopotamus must be located in a large area between Boŏtes and Lyra, with the crocodile extending on her back up to Serpens Caput, with its head at the head of Draco (Belmonte 2003; Lull 2005). The mooring posts in the hands of Reret would be located in the area of the tail of Draco and Ursa Minor."
On the left is an image of Set, an ancient Egyptian deity of the Red desert.
The second image down on the right is of Vajravārāhī.
"Vajravārāhī is one of the most popular female Tantric deities in all traditions of Tibetan Buddhism. She is shown one face, two hands and two legs, is usually red in colour, and standing in a dancing posture on a human corpse. She has a garland of human heads around her neck. She is also sometimes shown with a pig's head and that is why the name Varahi."
"Unlike the other planets in the Solar System, in English, Earth does not directly share a name with an ancient Roman deity. The name Earth derives from the eighth century [Old English language] Anglo-Saxon word erda, which means ground or soil. It became eorthe later, and then erthe in Middle English. These words are all cognates of Jörð, the name of the [Jötunn] giantess of Norse myth. The planet's name in Latin is the same as that of Terra in mythology Terra Mater, the Roman goddess, which translates to English as Mother Nature Mother Earth.
Earth has often been personified as a deity, in particular a goddess. In many cultures a mother goddess is also portrayed as a fertility deity. Creation myths in many religions recall a story involving the creation of the Earth by a supernatural deity or deities.
To the Aztec, Earth was called Tonantzin—"our mother"; to the Incas, Earth was called Pachamama—"mother earth". The Chinese Earth goddess Hou Tu is similar to [Gaia of mythology] Gaia, the Greek goddess personifying the Earth. To Hindus it is called Bhuma Devi, the Goddess of Earth. [...] also Graha.) In Norse mythology, the Earth giantess Jörð was the mother of Thor and the daughter of Annar. Ancient Egyptian mythology is different from that of other cultures because Earth is male, Geb, and sky is female, [Nut is a goddess] Nut.
"In Chinese Buddhism, Avalokiteshvara is often considered in a female form and know as Guanyin. In this painting on silk [on the right], she is shown sitting in western pure land (heaven). What is interesting is that at the bottom, some Tanguts are shown as playing musical instruments and dancing. There is pole on right that connects heaven with earth. On left, the figure in black cap is the emperor, who has died and is going to heaven. His grave also is shown next to him. In the upper right, the dead man is shown again, this time reborn as a boy, reaching out his hands to the Bodhisattva in prayer."
On the left is an image of the Mayan Moon goddess.
The Zodiacal light is a faint, roughly triangular, diffuse white glow seen in the night sky that appears to extend up from the vicinity of the Sun along the ecliptic or zodiac. It is best seen just after sunset and before sunrise in spring and autumn when the zodiac is at a steep angle to the horizon. Caused by sunlight scattered by space dust in the zodiacal cloud, it is so faint that either moonlight or light pollution renders it invisible. The zodiacal light decreases in intensity with distance from the Sun, but on very dark nights it has been observed in a band completely around the ecliptic. In fact, the zodiacal light covers the entire sky, being responsible for major part of the total skylight on a moonless night. There is also a very faint, but still slightly increased, oval glow directly opposite the Sun which is known as the gegenschein. The dust forms a thick pancake-shaped cloud in the Solar System collectively known as the zodiacal cloud, which occupies the same plane as the ecliptic. The dust particles are between 10 and 300 micrometres in diameter, with most mass around 150 micrometres.
"According to Gruson and Brugsch the Egyptians were acquainted with, and even worshipped, the zodiacal light from the very earliest times, as a phenomenon visible throughout the East before sunrise and after sunset. It was described as a glowing sheaf or luminous pyramid perpendicular to the horizon in summer, and inclined more or less during the winter. Indeed the Egyptians represented the zodiacal light under the form of a triangle which sometimes stood upright and at other times was inclined."
"There is one God, greatest among gods and men, neither in shape nor in thought like unto mortals ... He abides ever in the same place motionless, and it befits him not to wander hither and thither."
"Saturn, the old man who lives at the north pole, and brings with him to the children of men a sprig of evergreen (the Christmas tree), is familiar to the little folks under the name Santa Claus, for he brings each winter the gift of a new year."
"The religions of all ancient nations ... associate the abode of the supreme God with the North Pole, the centre of heaven; or with the celestial space immediately surrounding it."
"Lenormant, speaking of Rome and Olympia, remarks, "It is impossible not to note that the Capitoline was first of all the Mount of Saturn, and that the Roman archaeologists established a complete affinity between the Capitoline and Mount Cronios in Olympia, from the standpoint of their traditions and religious origin (Dionysius Halicarn., i., 34). This Mount Cronios is, as it were, the Omphalos of the sacred city of Elis, the primitive centre of its worship. It sometimes receives the name Olympos."1 Here is not only symbolism in general, but also a symbolism pointing to the Arctic Eden, already shown to be the primeval mount of Kronos, the Omphalos of the whole earth.2"
"As an offshoot of these Hellenistic speculations we should place Tacitus, Histories V,2: "Iudaeos Creta insula profugos novissima Libyae insedisse memorant, qua tempestate Saturnus vi Jovis pulsus cesserit regnis" (quoted from Loeb Classical Library)." i.e., "Jews were fugitives from the island of Crete and settled in Libya recorded the time when Saturn was driven from his throne by force of Jupiter".
"The motif of Saturn handing over power to Jupiter derives, of course, from Hesiod's account of the succession of the gods in his Theogony, and his story of the five successive ages of men -- the first, or golden, age being under the reign of Kronos (Saturn) and the following ages being under the reign of Zeus (Jupiter) -- in his Works and Days (110ff.). These stories were often retold. Ovid, for example, combines in his Metamorphoses the stories in the Theogony and Works and Days, telling us how, "when Saturn was consigned to the darkness of Tartarus, and the world passed under the rule of Jove, the age of silver replaced that of gold."8"
- Entities can be personifications of phenomena observed in the sky.
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- Chandrashekhar Athavale (6 March 2015). Black Castle of the desert- Part IV. Akshardhool. Retrieved 2015-10-08.
- Eva Heller, Psychologie de la couleur - effets et symboliques, pg. 17
- Blue, Jennifer (June 25, 2009). Planetary Nomenclature FAQ. Gazetteer of Planetary Nomenclature. Retrieved 2010-01-06.
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- Hein, Norvin. A Revolution in Kṛṣṇaism: The Cult of Gopāla: History of Religions, Vol. 25, No. 4 (May, 1986 ), pp. 296-317. www.jstor.org. JSTOR 1062622.
- James Rodney Hastings and John A Selbie (2003). Encyclopedia of Religion and Ethics (Volume 4 of 24 ( Behistun (continued) to Bunyan.) ed.). Edinburgh: Kessinger Publishing, LLC. p. 476. ISBN 0-7661-3673-6. Retrieved 2008-05-03.pp.540-42
- Couture, André (2006). [self.gutenberg.org/articles/Krishnology "The emergence of a group of four characters (Vasudeva, Samkarsana, Pradyumna, and Aniruddha) in the Harivamsa: points for consideration"]. Journal of Indian Philosophy 34 (6): 571–585. doi:10.1007/s10781-006-9009-x. self.gutenberg.org/articles/Krishnology.
- David N. Talbott (1980). The Saturn Myth. Garden City, New York, USA: Knopf Doubleday & Company, Inc. p. 419. ISBN 0-385-11376-5. Retrieved 2013-01-03.
- José Lull and Juan Antonio Belmonte (2015). Clive L.N. Ruggles (ed.). Egyptian Constellations, In: Handbook of Archaeoastronomy and Ethnoastronomy (PDF). New York: Springer. pp. 1478–86. doi:10.1007/978-1-4614-6141-8_148. ISBN 978-1-4614-6140-1. Retrieved 2015-10-08.
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|url=value (help). Springer. pp. 66–67. ISBN 0-306-46689-9.
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