Moon

Osiris (/oʊˈsaɪrɪs/, from Egyptian wsjr) was the god of fertility, agriculture, the afterlife, the dead, resurrection, life, and vegetation in ancient Egyptian religion. He was classically depicted as a green-skinned deity with a pharaoh's beard, partially mummy-wrapped at the legs, wearing a distinctive atef crown and holding a symbolic crook and flail. He was one of the first to be associated with the mummy wrap. When his brother Seth cut him to pieces after killing him, with her sister Nephthys, Osiris's sister-wife, Isis, searched Egypt to find each part of Osiris. She collected all but one – Osiris's genitalia. She then wrapped his body up, enabling him to return to life. Osiris was widely worshipped until the decline of ancient Egyptian religion during the rise of Christianity in the Roman Empire.

Osiris was at times considered the eldest son of the earth god Geb and the sky goddess Nut, as well as brother and husband of Isis, and brother of Set, Nephthys, and Horus the Elder, with Horus the Younger being considered his posthumously begotten son. Through syncretism with Iah, he was also a god of the Moon.

A lunar deity or moon deity is a deity who represents the Moon, or an aspect of it. These deities can have a variety of functions and traditions depending upon the culture, but they are often related. Lunar deities and Moon worship can be found throughout most of recorded history in various forms.

In ancient Greek mythology and religion, Selene (/sɪˈliːniː/; Ancient Greek: Σελήνη pronounced [selɛ̌ːnɛː] seh-LEH-neh) is the goddess and personification of the Moon. Also known as Mene (/ˈmiːniː/; Ancient Greek: μήνη pronounced [mɛ̌ː.nɛː] MEH-neh), she is traditionally the daughter of the Titans Hyperion and Theia, and sister of the sun god Helios and the dawn goddess Eos. She drives her moon chariot across the heavens. Several lovers are attributed to her in various myths, including Zeus, Pan, her brother Helios and the mortal Endymion. In post-classical times, Selene was often identified with Artemis, much as her brother, Helios, was identified with Apollo. Selene and Artemis were also associated with Hecate and all three were regarded as moon and lunar goddesses, but only Selene was regarded as the personification of the Moon itself.

Her equivalent in Roman religion and mythology is the goddess Luna.

Geocentrism is a superseded astronomical model description of the Universe with Earth at the center. It is also known as the geocentric model, often exemplified specifically by the Ptolemaic system. Under most geocentric models, the Sun, the Moon, stars, and planets all orbit Earth. The geocentric model was the predominant description of the cosmos in many European ancient civilizations, such as those of Aristotle in Classical Greece and Ptolemy in Roman Egypt, as well as during the Islamic Golden Age.

Two observations supported the idea that Earth was the center of the Universe. First, from anywhere on Earth, the Sun appears to revolve around Earth once per day. While the Moon and the planets have their own motions, they also appear to revolve around Earth about once per day. The stars appeared to be fixed on a celestial sphere rotating once each day about an axis through the geographical poles of Earth. Second, Earth seems to be unmoving from the perspective of an earthbound observer; it feels solid, stable, and stationary.

An eclipse is an astronomical event which occurs when an astronomical object or spacecraft is temporarily obscured, by passing into the shadow of another body or by having another body pass between it and the viewer. This alignment of three celestial objects is known as a syzygy. An eclipse is the result of either an occultation (completely hidden) or a transit (partially hidden). A "deep eclipse" (or "deep occultation") is when a small astronomical object is behind a bigger one.

The term eclipse is most often used to describe either a solar eclipse, when the Moon's shadow crosses the Earth's surface, or a lunar eclipse, when the Moon moves into the Earth's shadow. However, it can also refer to such events beyond the Earth–Moon system: for example, a planet moving into the shadow cast by one of its moons, a moon passing into the shadow cast by its host planet, or a moon passing into the shadow of another moon. A binary star system can also produce eclipses if the plane of the orbit of its constituent stars intersects the observer's position.

The sky is an unobstructed view upward from the surface of the Earth. It includes the atmosphere and outer space. It may also be considered a place between the ground and outer space, thus distinct from outer space.

In the field of astronomy, the sky is also called the celestial sphere. This is an abstract sphere, concentric to the Earth, on which the Sun, Moon, planets, and stars appear to be drifting. The celestial sphere is conventionally divided into designated areas called constellations.

A terrestrial planet is a class of planet that is composed primarily of silicate, rocks, or metals. It may instead be known as a tellurian planet, telluric planet, or rocky planet. Within the Solar System, the terrestrial planets accepted by the International Astronomical Union are the inner planets closest to the Sun: Mercury, Venus, Earth and Mars. Among astronomers who use the geophysical definition of a planet, two or three planetary-mass satellites – Earth's Moon, Io, and sometimes Europa – may also be considered terrestrial planets. The large rocky asteroids Pallas and Vesta are sometimes included as well, albeit rarely. The terms "terrestrial planet" and "telluric planet" are derived from Latin words for Earth (Terra and Tellus), as these planets are, in terms of structure, Earth-like. Terrestrial planets are generally studied by geologists, astronomers, and geophysicists.

Terrestrial planets have a solid planetary surface, making them substantially different from larger gaseous planets, which are composed mostly of some combination of hydrogen, helium, and water existing in various physical states.

Hecate (/ˈhɛkəti/ HEK-ə-tee; Ancient Greek: Ἑκάτη) is a goddess in ancient Greek religion and mythology, most often shown holding a pair of torches, a key, or snakes, or accompanied by dogs, and in later periods depicted as three-formed or triple-bodied. She is variously associated with crossroads, night, light, magic, witchcraft, drugs, and the Moon. Her earliest appearance in literature was in Hesiod's Theogony in the 8th century BCE as a goddess of great honour with domains in sky, earth, and sea. She had popular followings amongst the witches of Thessaly, and an important sanctuary among the Carians of Asia Minor in Lagina. The earliest evidence for Hecate's cult comes from Selinunte, in Sicily.

Hecate was one of several deities worshipped in ancient Athens as a protector of the oikos (household), alongside Zeus, Hestia, Hermes, and Apollo. In the post-Christian writings of the Chaldean Oracles (2nd–3rd century CE) she was also regarded with (some) rulership over earth, sea, and sky, as well as a more universal role as Savior (Soteira), Mother of Angels and the Cosmic World Soul (Anima Mundi).Regarding the nature of her cult, it has been remarked, "she is more at home on the fringes than in the centre of Greek polytheism. Intrinsically ambivalent and polymorphous, she straddles conventional boundaries and eludes definition."

A lunar phase or Moon phase is the apparent shape of the Moon's day and night phases of the lunar day as viewed from afar. Because the Moon is tidally locked to Earth, the cycle of phases takes one lunar month and moves across the same side of the Moon, which always faces Earth. In common usage, the four major phases are the new moon, the first quarter, the full moon and the last quarter; the four minor phases are waxing crescent, waxing gibbous, waning gibbous, and waning crescent. A lunar month is the time between successive recurrences of the same phase: due to the eccentricity of the Moon's orbit, this duration is not perfectly constant but averages about 29.5 days.

The appearance of the Moon (its phase) gradually changes over a lunar month as the relative orbital positions of the Moon around Earth, and Earth around the Sun, shift. The visible side of the Moon is sunlit to varying extents, depending on the position of the Moon in its orbit, with the sunlit portion varying from 0% (at new moon) to nearly 100% (at full moon).