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Amy Murdock Astronomy Jennifer Noon Ancient Worlds Report Ancient Egypt….. The ancient Egyptians were one of the first cultures to widely divide days into generally agreed-upon equal parts, using early timekeeping devices such as Sundials, Shadow Clocks, Merkhets & Plumb Lines used by astronomers of the period. Egyptians were considered to be one of the most advanced civilizations that had everything from sundials to high advanced irrigation systems to help with the droughts. They had the greatest library in the all the middle eastern empires, but was burnt down because of one jealous Roman Caesar and newly born Christens faith rebelled against the pagans and destroyed the most incredible landmarks that would’ve made a huge change into the present day we would have more understanding with many subjects that we now have difficulties with. Egyptian Worship & Planetary Movements: There were certain gods that were seen in the constellations, and others were represented by actual astronomical bodies. The constellation or group of stars that are called Orion this is represented by Osiris, who was the god of death, rebirth, and the afterlife. The Milky Way represented the sky goddess, Nut giving birth to the sun god Ra. In Egyptian mythology, stars were represented by the goddess of writing, Seshat, while the Moon was either Thoth, the god of wisdom and writing, or Khons, a child moon god. The horizon was extremely important to the Egyptians, this was where the Sun or Ra appeared and disappeared daily. A hymn to the Sun god Ra shows this reverence: 'O Ra! In thine egg, radiant in thy disk, shining forth from the horizon, swimming over the steel firmament.' The Sun itself was represented by several gods, depending on its position. A rising morning Sun was Horus, the divine child of Osiris and Isis. The noon Sun was Ra because of its incredible strength. The evening Sun became Atum, the god who was the creator, who lifted Pharaohs from their tombs to the stars. The red color of the Sun at sunset was considered to be the blood from the Sun (Ra) god as he died. After the Sun had set, it became Osiris, god of death and rebirth. In (Figure 1) This way, night was associated with death and day with life or rebirth; this would reflect the typical Egyptian idea of never ending of dying in the afterlife. Here is a few of the other gods and goddesses that represented something in the sky for the Ancient Egyptians.: Horus was the Hawk is the Sun in totality. The Sun god Atum is the eclipsed Sun passing the second contact of a total eclipse. Ra was also the eclipsed Sun shining past the third contact as the Diamond Ring. The Scarab Khepri was the representation of the dark New Moon. The Great Sphinx was the Egyptian Lord of Solar Eclipses. Hathor, the cow goddess, was the Egyptian Goddess of Solar Eclipses In 1100 B.C.E., Amenhotep wrote "Catalog of the Universe" in which he identified the major known constellations. Unfortunately, the catalog does not mention either Sirius or any of the planets previously known to the Egyptians. At least outwardly, there are no surviving inscriptions or documents to indicate that the Egyptian knowledge of astronomy was more than tomb decoration, and not protected over the ages, more as a body of knowledge. When the Vienna papyrus which described lunar and solar eclipses and their portent was probably copied by a scribe in the late second century AD, and presents knowledge of astronomy that is regarded as Babylonian in nature. Eternal Egypt posts that during the Greco-Roman era, Claudius Ptolemy, an astronomer, mathematician, and geographer, worked from the data of past astrologers to map over 1,000 stars. He compiled a list of 48 constellations and described the longitude and latitude lines of the earth. He was a believer that the earth was the center of the universe and worked to advance this theory. He developed the Ptolemaic system to explain why some planets seemed to move backwards for periods of time in their orbit around earth. He theorized that each planet also revolved in a smaller circle as well as a larger one. This was called the "epicycle." This theory would survive for 1400 years, until it was finally accepted that the earth was itself another planet in orbit around the sun.” Solar Eclipses: There is always a discussion with astronomers of the presumed knowledge of solar eclipses by the ancient Egyptians is beyond the scope of these brief comments. Since, it is pertinent to note that some Greek writers gave priority to Egypt in astronomical knowledge. There is no documentation of the Egyptians specifically mentioning solar eclipses. However, that the Egyptians possessed accurate knowledge of eclipses is evident from external sources of recorded pages by the other great conquering countries. Diodorus Siculus (200 A.D.) stated categorically that the ancient Egyptian astronomers possessed the ability to predict solar eclipses. Plutarch related that the ancient Egyptians explained solar eclipses by the passage of the Moon between the Sun and the earth in daylight hours. There is evidence, admittedly disputed by some writers, that an actual solar eclipse was reported in Egypt in the 9th century B.C. and again in 610 B.C. The report of this latter eclipse has been attributed to Thales, though others, e.g., Herodotus, claim that Thales actually predicted an eclipse in 584 B.C. Thales, Greece's first "philosopher", was actually of Phoenician birth and spent seven years studying in Egypt. Greek commentators attribute Thale's mathematical and astronomical knowledge to this apprenticeship in Egypt (" Ancient Egypt"). The golden age of Greek science commences with the Ptolemaic dynasty (330 B.C.) in Egypt, in which the building of Alexandria and the founding of the city's Greatest Library was built. The major Greek astronomers studied there along with several of the Alexandrian astronomers which were considered Greek, were actually Egyptians who had adopted or been given Greek names. One such person was Ptolemy (150 A.D.), author of the Almagest, the most important astronomical text until the middle Ages, whose knowledge of solar eclipses is well-documented. Also, Clement of Alexandria (2nd century A.D.), author of Stromateis described 49 books of Thoth preserved by the priests of ancient Egypt, at least four of them treating astronomical subjects. One book dealt with the "constitution of the Sun and Moon" and another "the conjunctions and variations of the light of the Sun and Moon." That the ancient astronomer-priests of Egypt could and did predict eclipses was considered axiomatic. Information detailing Egyptian priesthood repeatedly confirms the remarkable ability of that priesthood to predict solar eclipses. Practical Uses of the Stars: The Egyptian civilizations were based around the Nile River, which flooded every year at the same time and provided rich soil for agriculture this river was the center of life in Egypt. The Egyptian astronomers, who were the priests; they recognized that the flooding always occurred at the summer solstice, which was also when the bright star Sirius (Sirius, the "Dog Star"), rose before the Sun. Priests were thought to be powerful since they were able to predict the annual flooding of the Nile River. This happened around June 25, before the Nile was dammed, but from 3,000 B.C.E. to 1,000 B.C.E., the rising of Sirius at sunrise came close enough to the annual flooding at the ancient capital of Memphis. Their entire survival was centered on the annual flooding of the Nile, and the planets' motions did not affect this flooding (Lockyer). Many Egyptian buildings were built with an astronomical orientation. Many temples and pyramids were constructed in relation to the stars, zodiac, and constellations this was to bring Pharaohs and their families closer to the gods in the afterlife. In different cities, the buildings had different orientations based on the specific religion of that place, some temples were constructed to align with a star that either rose or set at harvest or sowing time. Other buildings were oriented toward the solstices or equinoxes so the sun or stars would hit it perfectly in the light of the sun. As early as 4000 B.C. E., temples were built so that sunlight entered a room at only one precise time of the year (" Ancient Egypt"). As an alternative building method was to gradually narrow successive doors into a specific room, in order to concentrate the sunbeams onto a certain god's image on the wall. The designs sometimes became quite complex. At the temple of Medinet Habu, shown below with relative with the temples on site, there are actually two buildings which are slightly off-kilter. It has been suggested that the second one was built when the altitude of the other temple's orientation stars changed over a long period of time ("Eternal Egypt"). Astronomers found many connections between the Orion constellation and the way ancient Egyptians built the Great Pyramids. Orion's "belt" was the three stars in the middle of his belt that the arrangement of the three Pyramids on the Giza Strip (including the Great Pyramid), the third pyramid which was a little smaller and above the line formed by the other two pyramids. King Khufu, ruler of the fourth dynasty built the Great Pyramid at Giza he had his tomb facing circumpolar star so he could go to the afterlife with the gods. “The door was facing north and is about 16.8 meters or 55.1 above ground level,” states the Eternal Egypt website. Within the Great Pyramids are southern facing airshafts that point to the star Sirius, with its significance in marking the start of the Egyptian year, and to Orion, associated with death and rebirth, another recurring theme in Egyptian mythology ("Eternal Egypt"). This was done when the Egyptians also divided the stars into 36 "decans" (each spanned 10° of a 360° circle). Each decan had its group of associated stars. These stars are represented in tombs and elsewhere. However, Egyptians did not seem to develop advanced theories about the motions of the planets. The oldest example of the earliest sundial is Egyptian from about 1500 BC. Several numerous temple and pyramid alignments and several papyrus codices suggest a sophisticated knowledge of trigonometry and algebra; no similar astronomy documents survive, or records of astrological observations. Egyptians’ Calendar: The Egyptians found that the stars were more accurate over thousands of years than their solar calendar of 365 days. Since the Egyptian calendar did not have leap years, their year cycled through the seasons completely every 365 times 4, or 1460 years (" Ancient Egypt"). This was known as a "Cycle of Sothis" because Sothis (Sirius) would rise with the Sun on the same day every 1460 years this was the precession of the equinoxes and proper motion of Sirius the period was slightly less, but Egyptians found this cycle of 1460 years (Lockyer). Although the Egyptians knew of this quarter-day error, they maintained their 365-day calendar for ceremonial purposes. Their year was divided into twelve 30-day months, followed by a five day feast period that was not considered lucky for any work in the city. Over the period of time, Ancient Egypt's history of three thousand years, the months completely rotated through the seasons at least twice. Everything we know about ancient Egyptian civilization's knowledge of astronomy comes to us from tomb paintings, various temple inscriptions, and a handful of papyrus documents such as the Rhind Papyrus. Sadly, when the Great Library in Alexandria was burned during the time of Cleopatra and Julius Caesar. These burnings in AD 390 and AD 640 destroyed an estimated 400,000 books on Egyptian secular literature, mathematics, medicine, and astronomy. Only thing that survives is fragments that some scholars see as merely the faded ghosts of Egyptian intellectual legacy. The fabulous astrological ceiling of Senmut painted around 1460 BC, includes celestial objects such as Orion, Sirius, and the planets Mercury, Venus, Jupiter, and Saturn. The oldest known copies of an almanac date from 1220 BC at the time of Ramses the Great. Astronomical Tools: Priests that observed the skies were always observing the midnight skies when all the stars and planets were out in abundance. The tools that they used were called indicators These helped observed the circumpolar star. The ancients would draw a noth-south axis line on the ground marking the correct direction the buildings were supposed to be built ("Eternal Egypt"). It also consisted of a horizontal, narrow wooden bar with a hole near one end, through which the astronomer would look to fix the position of the star. The other instrument, called the "bay en imy unut," or palm rib, had a V-shaped slot cut in the wider end through which the priest in charge of the hours looked to fix the star. In these times when people's activities were limited to daylight, shadow-casting instruments called gnomons were used to distinguish broad divisions in the daytime. Gnomons were eventually combined with scales to produce sundials, which allowed people to tell time by measuring the length or direction of the shadow cast by the Sun. An Egyptian Sundial from about 1500 B.C. provides the earliest evidence of the division of the day into equal parts. Marks on the dial link the length of the gnomon's shadow to a standardized unit. So before the ancient Egyptians made the first Sundials, they calculated the division of the day-night period into 24 equal hours, the number of hours counted during any period of daylight was held constant across the seasons; thus, an hour in summer lasted longer than an hour in winter because the daylight period it was longer. Sundials had to be specially made for different latitudes because the Sun's altitude in the sky decreases at higher latitudes, producing longer shadows than at lower latitudes. Not everyone in the ancient world realized this. Interestingly, a Sundial brought to Rome from Catania, Sicily. Told Romans the incorrect time for almost a century. The Astrolabe, which they inherited from the Greek civilization, when Alexandria was burnt to the ground Muslim astronomers were taking care of the astrolabe. They also developed it, and wrote great valuable books on how to use it. To use this remarkable device, the astrolabe, continued until the nineteenth century and it is not known specifically who invented it, some referred to the Greek Scientist Hipparchus,(this I heard was a woman scientist,) she was a wonderful mathematician of Algebra. When the Christens took over Alexandria the Astrolabe was taken from her when she was being tortured, killed and burn for being a witch. In wonderment they have changed the gender of the scientist to a man. Knowledge of the rest of his/her work relies on secondhand reports, especially in the great astronomical compendium the Almagest, written by Ptolemy in the 2nd century A.D Then a Muslim scientist Mohammed bin Ibrahim al-Fazari (died in 180 AH) is the first scientist to write a book in description, manufacture, and the use of the astrolabe, and he was the first who have made Astrolabe in Islam. Muslim scholars and scientists concerned about the Astrolabe and gave much attention to its huge role in determining the times of worship (Prayers), the direction of Mecca, and the solar and lunar eclipses, as well as its important role in astronomy and making Zij (Astronomical Almanac), determining distances, and to identify scientific measurements and most importantly the knowledge of the time at night by the stars and during the day by the sun , so The members of our astronomical society made a lot of astrolabes to understand it and to know how to use it ("Eternal Egypt"). “Astrolabes are used to show how the sky looks at a specific place at a given time. This is done by drawing the sky on the face of the astrolabe and marking it so positions in the sky are easy to find. To use an astrolabe, you adjust the moveable components to a specific date and time. Once set, much of the sky, both visible and invisible, is represented on the face of the instrument. This allows a great many astronomical problems to be solved in a very visual way. The uses of the astrolabe include finding the time during the day or night, finding the time of a celestial event such as sunrise or sunset and as a handy reference of celestial positions. Astrolabes were also one of the basic astronomy education tools in the late middle Ages. Old instruments were also used for astrological purposes. The typical astrolabe was not a navigational instrument although an instrument called the mariner's astrolabe was widely used in the Renaissance. The mariner's astrolabe is simply a ring marked in degrees for measuring celestial altitudes.” states the website deicated to the Astrolabe ("ASMM"). Even though Ancient Egypt fell on the last dynasty with Cleopatra and Marc Antony at its rule, the culture had flourish and broke many new heights of literature, mathematics, and even astronomy. These few main points are what made them so well Civilized and a better community of tactics that defended there empire. Works Cited Pictures: Figure 1. Play to Game. 2010. Google Web. 4 Dec 2012. <http://www.playtogame.com/games/empire-builder-ancient-egypt/>. Figure 2: School Work Helper. 2010. Google Web. 4 Dec 2012. <http://schoolworkhelper.net/wp-content/uploads/2012/05/egyptian-calendar.jpg>. Figure 3: J Norman Locker, the Dawn of Astronomy, MIT Press, 1894.Egyptian Papyrus. http://www.anthonykosky.com/Egypt/papyrus.html. Medinet Habu. http://www.museumphotography.com/mhabu.htm. Figure 4: © 2007 AARS. Algunos derechos reservados. Si utiliza contenido, y de acuerdo con la licencia CC by-nc-sa, deberá enlazarlo o referenciarlo an http://relojesdesol.info;http://www.relojesdesol.info/node/945, Sources: J Norman Lockyer, the Dawn of Astronomy, MIT Press, 1894.Egyptian Papyrus. http://www.anthonykosky.com/Egypt/papyrus.html. Medinet Habu. http://www.museumphotography.com/mhabu.htm. "Astronomy." Eternal Egypt. N.p., n.d. Web. 4 Dec 2012. <http://www.eternalegypt.org/EternalEgyptWebsiteWeb/HomeServlet?ee_website_action _key=action.display.topic.details&language_id=1&context_id=30795&trait_item_id=100 00203>. ("Eternal Egypt") "Astronomy." Ancient Egypt. N.p., n.d. Web. 4 Dec 2012. <http://www.crystalinks.com/eclipse.html>. (" Ancient Egypt") "Astronomical Devices." ASMM. ASMM, n.d. Web. 4 Dec 2012. http://www.crystalinks.com/eclipse.html. ("ASMM") Lockyer , J Norman . "Medinet Habu,Egyptian Papyrus." Medinet Habu,Egyptian Papyrus. (1894): n. page. Web. 4 Dec. 2012. <http://www.museumphotography.com/mhabu.htm>.http://www.anthonykosky.com/Egy pt/papyrus.html>. (Lockyer )