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RE: Ancient Astronomers

Ursa Major
Ancient Egyptian astronomers aligned the pyramids due north by using two stars that circle the celestial polar point.
The north-finding stars were Kochab, in the bowl of the Little Dipper (Ursa Minor), and Mizar, in the middle of the handle of The Plough or Big Dipper (Ursa Major ).
Nearly 4,500 years ago, the pair was about 10 degrees away from the celestial pole, which lay directly between them. The ancient astronomers, using a plumb line exactly intersected both stars, could find a line that pointed exactly due north when one star was above the other in the sky.
But the alignment was only true for a few years around 2,467 BC. Either side of this date, the stars deviated from true north. Anyone that used this method to plot a direction would have made errors.
And it is these mistakes that can be used to estimate very accurately the exact dates when pyramids were built. The orientation errors of earlier and later pyramids faithfully track the slow drift of Kochab and Mizar.
The measurements suggests that the Great Pyramid at Giza was constructed in 2,480 BC. (With an error of 10 years)

Ancient astronomy

Kate Spence from the University of Cambridge developed the theory that explains the deviations in the alignment of the bases of many pyramids from true north.
The Earth's axis wobbles like a gyroscope over a period of 26,000 years a process called procession.

"We know that the ancient Egyptians were extremely interested in the night sky, particularly the circumpolar stars,"

The pair of stars circles around the North Pole, and because they were circumstellar, the Egyptians astronomers called them 'The Indestructibles'.

"As a result, they became closely associated with eternity and the king's afterlife. So that after death, the king would hope to join the circumpolar stars - and that's why the pyramids were laid out towards them."

Click to enlarge!

Ursa Major is a large sprawling constellation, the third largest in fact.

It was known to the ancient Greeks as the Bear and the Wagon and to the Romans as Ursa Major (the Great Bear)

The name "The Great Bear" seems to have been assigned to the constellation in antiquity. Interestingly, a number of North American tribes (Algonquin, Iroquois, Illinois, and Narragansett, among possibly others) also associated the constellation with a gigantic bear. In ancient Sumer, the Dipper was called Ma-God-Da, the flying Wagon, and in Hebrew, Agalah, which has the same meaning.

In Greek mythology Callisto, daughter of King Lycaon, was chosen as a young child to be one of Artemis's companions. Artemis was Apollo's sister. Artemis gathered about her a number of young nymphs. Reflecting her own vows on chastity, she also required complete fidelity from these young women (One of these was Callisto). Zeus seduces the young maiden Callisto. And when Artemis discovered that Callisto was pregnant, she took her revenge. . So she transformed Callisto into a bear. Her plan was to have Callisto, as a bear, hunted down and killed. But Zeus took pity, and sent Callisto to the heavens, keeping the same form of a bear.

  Listen: .Ancient Astronomers(part1)
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In Europe, the pattern is known as the Plough, Charles's (Charlemagne's) Wain, and the Wagon. Of the seven stars constituting the Big Dipper, six are of the second magnitude and one is of the third magnitude. Two of the second-magnitude stars, alpha and beta Ursa Major, which form the outer edge of the bowl, point directly. to Polaris, and hence are called the Pointers. At the bend of the handle of the Big Dipper is the readily visible double star known as Mizar, or zeta Ursa Major. Mizar, the first visual double star discovered, consists of two components having magnitudes of 2.4 and 4.
All the stars orbit the center of the Milky Way galaxy, as does our own Sun. As a result, they appear to move in an effect known as "proper motion". The motion is extremely small, but quite noticeable over thousands of years.




Most of the stars making up the Big Dipper show a common proper motion, as R.A. Proctor discovered in 1869. When their radial velocities were determined from their spectra, by W. Huggins in 1872, it became clear that they move in the same direction. They are all members of a physical star cluster. It turns out that the motion is east and south. It has a convergence point about 130 degrees away in eastern Sagittarius, approximately at RA 20:24 and Dec -37. The cluster is currently approaching us at 10 km/sec.

This cluster is centered at a distance of about 75 light years from our solar system.
It covers an enormous portion of the sky (30 light years by 18 light years), and probably includes the outlying member Alpha Coronae Borealis, which is 30 degrees off. The stars are similar to those found in the "hyades" and M44 indicating that this cluster is of roughly the same age (400 million years) as the other two.
Studies of the motions of other nearby stars show that a number of conspicuous stars, together with about 100 fainter stars, in our neighbourhood show motion in about the same direction in space. These stars include Sirius , Alpha Ophiuchi, Delta Leonis, and Beta Aurigae. It seems that these stars are cluster members and they all have a common direction and motion. All these stars are sometimes referred to as the Ursa Major Stream, which encompass more than 100 light years from the cluster's center. Our Solar System is located in the outskirts but within the extent of this stellar stream.

This is our Galaxy!...Yes Really!

The Great Pyramid of Giza

The Great Pyramid of Giza stands on the northern edge of the Giza Plateau, located about 10 miles west of Cairo. The Great Pyramid of Giza is one of the seven wonders of the ancient world. It is the largest building in size, around 90,000,000 cubic feet in the world. The mathmatical dimensions of this stone are based on Pi (3.14) and the Pythagorean Theorem . The builders had squared the circle.

The position of the three Great Pyramids and their relation to the Nile created on the ground a sort of `map`of the three stars of Orion's belt and their relative position to the Milky Way.
Also the inclined shaft in the Great Pyramid was aimed at the three stars. The best alignment for the Giza Pyramids/Nile pattern with the Orion's belt/Milky Way pattern occurred during the epoch of 10,500 BC The builders wanted us to know that there was something significant about that date and those stars.


Giza pyramid

Long before the pyramids were constructed in Egypt, ancient people there built elaborate structures aligned to the sun and stars. There is an alignment to the former position of Orion's belt The standing megaliths and ring of stones were erected from 6.700 to 7,000 years ago in the southern Sahara desert. They are the oldest dated astronomical alignment discovered so far and bear a striking resemblance to Stonehenge and other megalithic sites constructed a millennium later in England, Brittany, and Europe.


Nabta Playa

The site, near Nabta in the Nubian Desert, was discovered in 1974 by a group of scientists headed by Fred Wendorf, an Anthropology Professor from Southern Methodist University in Texas. It consists of a small stone circle, a series of flat, tomb-like stone structures (containing the bones of cattle) and five lines of standing and toppled megaliths.
For nomadic tribes during the early part of the Holocene epoch, Nabta Playa was a ceremonial center . Located 100 km west of Abu Symbol in southern Egypt, Nabta contains a number of megaliths. They predate Stonehenge and other similar prehistoric sites by at least 1000 years.
Humans had occupied the Nabta area for thousands of years, from 11,000 years ago up until about 4,800 years ago. A climatic change made Nabta a habitable area around 12,000 years ago.
Most of the stone structures and other artefacts were dated between 7,000 and 6,500 years ago.
They constructed five megalithic alignments that radiated from a cluster of stones that has been named E-96-1 Structure A. These megaliths were constructed out of quartzite sandstone, some of which are nine feet-high, that came from exposed outcrop of sandstone that was at least a half -kilometer away from the site. . Each is embedded in the soil on top of a shaped table rock
The alignments of the megaliths form an east-west line and another alignment forms a north-south line.
Three hundred meters north of these alignments is the stone calendar circle. Compared to Stonehenge, this circle is very small, measuring roughly 4 m in diameter. The stone-circle consists of a number of stones, the main ones being four pairs of larger ones. Two of these pairs align to form a line very close to a true north-south line, and the other two pairs align to form an east-west line. The centerline of one slot between the slabs would have picked up the first gleam of the rising sun at the summer solstice. The east-west alignment is calculated to be where the sun would have risen and set from the summer solstice 6,500 years ago.

Because Nabta is close to the Tropic of Cancer, the noon sun is at its zenith on two days, about three weeks before and after the summer solstice. On these days, upright objects do not cast shadows--something that was significant to ancient people.

"The nomadic groups must have engaged in a variety of activities during summer occupation, such as social bonding, marriage, trade and ritual,"

The area received enough rain in the summer monsoon for temporary lakes, called playa, to form. The individual stone monoliths would have been partially submerged in the lake.

"The organization of the megaliths suggests a symbolic geometry that integrated death, water, and the sun,"

Like the modern African Massai, the late Neolithic population apparently used cattle in their rituals .

The Rise of the Egyptian Empire.

About 4,800 years ago there was another climatic change. The African monsoons shifted south to approximately the same area that they were prior to 12,000 years ago. The land became hyper-arid again and caused human habitation at Nabta to cease.
But where did these people go? Perhaps the people of Nabta migrated to the Nile Valley. The development of the monumental buildings of ancient Egyptian civilization was hastened by the arrival in the Nile valley of well-organized nomadic groups with a sophisticated cosmology.
This theory explains the prominence of cattle in the religious belief system of Pre-dynastic Egypt continuing into the Old Kingdom.
In ancient Egypt, cattle were deified and regarded as the earthly representative of the gods. An Egyptian god that is represented by a bull is the god of rain, a very important entity to the people of Nabta, considering that life or death could have been determined by the amount of rain they received.
One of the earliest pyramids and one of the world's oldest major stone structures are the step pyramid at Saqqara. It was built 500 years after the changing climate rendered Nabta uninhabitable. . It was built in the 3rd Dynasty (around 2630 BC) for King Djoser and its construction was overseen by his vizier Imhotep. It may have incorporated astronomical features known to the ancient Nubians.
Saqqara is an immense necropolis (cemetery) just south of Cairo and west of the ancient city of Memphis of which very little remains. Used as a burial ground for thousands of years. The site stretches six kilometres from north to south and more than 1.5 kilometres across at its widest point.

The prediction of the seasons are needed by an agrucultural society.
And strange as it may seem, astronomy was a religion in ancient Egypt.

And to the ancient astronomers the stars gave order to a chotic time in human history. And like other astronomer priests in emerging agrucultural societies they brought order and reasurance from the transient nomadic hunter-gather way of life.
In fact, Cosmos means order...
As mentioned before the secret passages in the great pyramid point to the `indestructable` stars; but there are other clues to this hidden astronomical wisdom.
In an ancient story , RA the sun-god is mocked by the people, because he is becoming old and weak; Ra sends Hathor to punish mankind, Unfortunatly Hathor goes on a killing spree and is about to destroy everyone, so Ra pours 7000 pots of beer into the Nile and Hathor sees her reflection in the swollen river and stops the carnage. This story describes the annual nile floods. Hathor is associated with the dog star, Sirus. When Ra becomes weak, the sun is low , sirus rises before the sun just at the time of the annual Nile flood.

Another story describes how in the morning the goddess Nut give birth to Ra; Ra travels across the sky with Thoth and Matt in a heavenly boat; and at dusk Nut swollows him. The milky-way is Nut, and when drawn looks like a human figure the position of the sun appears near the `birth canal` and 9 months later at her `mouth`. 9 months is of course the human gestation period.
The egyptian thought there were only 360 days in a year at firt. But eventually they added an extra 5 days....why this accuracy for an agricultural society? why 365 days?
Because their social economy required it.
But this number still survives in the 360 compass degrees.

Egyptian society had advanced so much that they required an accurate calander and time scale.
In a story, Osirus had to travel through twelve gates during his journey across the back of Nut. These Twelve gates are 12 stars that rise and set...
They had originally 18 bright stars to mark and divide the sky, but due due to dusk and dawn, 6 stars are lost from view...12 stars were used to mark time through the night...This gives rise to the twelve zodic signs and our time scale of 24 hours a day.
Thoth was the god of wisdom and Time, govener of the moon. The moon forms a natural clock. The egyptian were one of the first civilisation to devide the year into months. A strange story describes how the god Horus(Mars) impregnated the god Set(chaos) and the resulting planet-child was claimed by Thoth.
The new planet created was the moon. The egyptian gods were not just a tool to describe astronomy, they were also a tool to describe morals....
Morals needed by a new, emerging, way of life; civilisation.
The astronomers were the priests, and the things that they observed in the heavens they related directly to the things they observed on the earth.
It maybe speculated that the locations and position of the great pyramids are a gigantic `map` of the cosmos. It may have been their way to directly bring heaven onto earth.

As a side note, the history of the river Nile is surprisingly short....
It was only one million years ago that a large uplifting, of the area that would become the Lake Victoria plateau and the `Moon mountains`, formed.
The newly formed mountains then collected the rain and (due to a slight sagging of the crust) created the Victoria Lake chain that would eventually form the head of the Nile.
The actual Nile only burst out of the lake system, and flowed north, only several thousand years before the establishment of the Egyptian civilisation...

-- Edited by Blobrana at 19:34, 2007-10-07



Posts: 131433

Title: The Persian-Toledan Astronomical Connection and the European Renaissance
Authors: M. Heydari-Malayeri (LERMA, Observatoire de Paris, France)

This paper aims at presenting a brief overview of astronomical exchanges between the Eastern and Western parts of the Islamic world from the 8th to 14th century. These cultural interactions were in fact vaster involving Persian, Indian, Greek, and Chinese traditions. I will particularly focus on some interesting relations between the Persian astronomical heritage and the Andalusian (Spanish) achievements in that period. After a brief introduction dealing mainly with a couple of terminological remarks, I will present a glimpse of the historical context in which Muslim science developed. In Section 3, the origins of Muslim astronomy will be briefly examined. Section 4 will be concerned with Khwarizmi, the Persian astronomer/mathematician who wrote the first major astronomical work in the Muslim world. His influence on later Andalusian astronomy will be looked into in Section 5. Andalusian astronomy flourished in the 11th century, as will be studied in Section 6. Among its major achievements were the Toledan Tables and the Alfonsine Tables, which will be presented in Section 7. The Tables had a major position in European astronomy until the advent of Copernicus in the 16th century. Since Ptolemy's models were not satisfactory, Muslim astronomers tried to improve them, as we will see in Section 8. This Section also shows how Andalusian astronomers took part in this effort, which was necessary in the path to the Scientific Revolution. Finally, Section 9 presents the Spanish influence on the eve of the Renaissance.

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