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  • #46

    Stonehenge


    Stonehenge is a prehistoric monument located in the English county of Wiltshire, about 3.2 kilometres (2.0 mi) west of Amesbury and 13 kilometres (8.1 mi) north of Salisbury. One of the most famous prehistoric sites in the world, Stonehenge is composed of earthworks surrounding a circular setting of large standing stones. Archaeologists had believed that the iconic stone monument was erected around 2500 BC. However one recent theory has suggested that the first stones were not erected until 2400-2200 BC, while another suggests that bluestones may have been erected at the site as early as 3000 BC.
    The surrounding circular earth bank and ditch, which constitute the earliest phase of the monument, have been dated to about 3100 BC. The site and its surroundings were added to the UNESCO's list of World Heritage Sites in 1986 in a co-listing with Avebury henge monument, and it is also a legally protected Scheduled Ancient Monument. Stonehenge itself is owned by the Crown and managed by English Heritage while the surrounding land is owned by the National Trust.
    New archaeological evidence found by the Stonehenge Riverside Project indicates that Stonehenge served as a burial ground from its earliest beginnings. The dating of cremated remains found that burials took place as early as 3000 B.C, when the first ditches were being built around the monument. Burials continued at Stonehenge for at least another 500 years when the giant stones which mark the landmark were put up.









    History Stonehenge itself evolved in several construction phases spanning at least some 1500 years. However there is evidence of large scale construction both before and afterwards on and around the monument that perhaps extends the landscape's time frame to 6500 years.
    Dating and understanding the various phases of activity at Stonehenge is not a simple task; it is complicated by poorly kept early excavation records, surprisingly few accurate scientific dates and the disturbance of the natural chalk by periglacial effects and animal burrowing. The modern phasing most generally agreed by archaeologists is detailed below. Features mentioned in the text are numbered and shown on the plan, right, which illustrates the site as of 2004. The plan omits the trilithon lintels for clarity. Holes that no longer, or never, contained stones are shown as open circles and stones visible today are shown coloured. It is widely assumed that Stonehenge once stood as a magnificent "complete" monument; we should be aware that this cannot be proved, since around half of the stones that should be present are in fact missing, and since many of the assumed stone sockets have never actually been recorded through excavation.
    Before the monument (8000 BC forward)
    Some archaeologists have found four (or possibly five, although one may have been a natural tree throw) large Mesolithic postholes which date to around 8000 BC nearby, beneath the modern tourist car-park. These held pine posts around 0.75 metres (2.5 ft) in diameter which were erected and left to rot in situ. Three of the posts (and possibly four) were in an east-west alignment and may have had ritual significance; no parallels are known from Britain at the time but similar sites have been found in Scandinavia. At this time, Salisbury Plain was still wooded but four thousand years later, during the earlier Neolithic, a causewayed enclosure at Robin Hood's Ball and long barrow tombs were built in the surrounding landscape. In approximately 3500 BC a large cursus monument was built 700 metres (2,300 ft) north of the site as the first farmers began to clear the forest and exploit the area.
    Stonehenge 1 (ca. 3100 BC)
    The first monument consisted of a circular bank and ditch enclosure made of Late Cretaceous (Santonian Age) Seaford Chalk, (7 and 8) measuring around 110 metres (360 ft) in diameter with a large entrance to the north east and a smaller one to the south (14). It stood in open grassland on a slightly sloping but not especially remarkable spot. The builders placed the bones of deer and oxen in the bottom of the ditch as well as some worked flint tools. The bones were considerably older than the antler picks used to dig the ditch and the people who buried them had looked after them for some time prior to burial. The ditch itself was continuous but had been dug in sections, like the ditches of the earlier causewayed enclosures in the area.
    The chalk dug from the ditch was piled up to form the bank. This first stage is dated to around 3100 BC after which the ditch began to silt up naturally and was not cleared out by the builders. Within the outer edge of the enclosed area was dug a circle of 56 pits, each around 1 metre (3.3 ft) in diameter (13), known as the Aubrey holes after John Aubrey, the seventeenth century antiquarian who was thought to have first identified them. The pits may have contained standing timbers, creating a timber circle although there is no excavated evidence of them. A recent excavation has suggested that the Aubrey Holes may have originally been used to erect a bluestone circle.[6] If this were the case it would advance the earliest known stone structure at the monument by some 500 years. A small outer bank beyond the ditch could also date to this period.
    Stonehenge 2 (ca. 3000 BC)
    Evidence of the second phase is no longer visible. It appears from the number of postholes dating to this period that some form of timber structure was built within the enclosure during the early 3rd millennium BC. Further standing timbers were placed at the northeast entrance and a parallel alignment of posts ran inwards from the southern entrance. The postholes are smaller than the Aubrey Holes, being only around 0.4 metres (16 in) in diameter and are much less regularly spaced. The bank was purposely reduced in height and the ditch continued to silt up. At least twenty-five of the Aubrey Holes are known to have contained later, intrusive, cremation burials dating to the two centuries after the monument's inception. It seems that whatever the holes' initial function, it changed to become a funerary one during Phase 2. Thirty further cremations were placed in the enclosure's ditch and at other points within the monument, mostly in the eastern half. Stonehenge is therefore interpreted as functioning as an enclosed cremation cemetery at this time, the earliest known cremation cemetery in the British Isles. Fragments of unburnt human bone have also been found in the ditch fill. Late Neolithic grooved ware pottery has been found in connection with the features from this phase providing dating evidence.
    Stonehenge 3 I (ca. 2600 BC)
    Archaeological excavation has indicated that around 2600 BC, timber was abandoned in favour of stone, and two concentric arrays of holes (the Q and R Holes) were dug in the centre of the site. These stone sockets are only partly known (hence on present evidence are sometimes described as forming Œcrescents¹), however they could be the remains of a double ring. Again, there is little firm dating evidence for this phase. The holes held up to 80 standing stones (shown blue on the plan) only 43 of which can be traced today.
    About 2,000 BC, the first stone circle (which is now the inner circle), comprised of small bluestones, was set up, but abandoned before completion. The stones used in that first circle are believed to be from the Prescelly Mountains, located roughly 240 miles away, at the southwestern tip of Wales. The bluestones weigh up to 4 tons each and about 80 stones were used, in all. Given the distance they had to travel, this presented quite a transportation problem.
    Modern theories speculate that the stones were dragged by roller and sledge from the inland mountains to the headwaters of Milford Haven. There they were loaded onto rafts, barges or boats and sailed along the south coast of Wales, then up the Rivers Avon and Frome to a point near present-day Frome in Somerset. From this point, so the theory goes, the stones were hauled overland, again, to a place near Warminster in Wiltshire, approximately 6 miles away. From there, it's back into the pool for a slow float down the River Wylye to Salisbury, then up the Salisbury Avon to West Amesbury, leaving only a short 2 mile drag from West Amesbury to the Stonehenge site.

    The Blue Stones

    The bluestones (some of which are made of dolerite, an igneous rock), were thought for much of the 20th century to have been transported by humans from the Preseli Hills, 250 kilometres (160 mi) away in modern day Pembrokeshire in Wales. A newer theory is that they were brought from glacial deposits much nearer the site, which had been carried down from the northern side of the Preselis to southern England by the Irish Sea Glacier.
    Other standing stones may well have been small sarsens, used later as lintels. The stones, which weighed about four tons, consisted mostly of spotted Ordovician dolerite but included examples of rhyolite, tuff and volcanic and calcareous ash; in total around 20 different rock types are represented. Each monolith measures around 2 metres (6.6 ft) in height, between 1 m and 1.5 m (3.3-4.9 ft) wide and around 0.8 metres (2.6 ft) thick. What was to become known as the Altar Stone (1), is is almost certainly derived from either Carmarthenshire or the Brecon Beacons and may have stood as a single large monolith.
    The north eastern entrance was also widened at this time with the result that it precisely matched the direction of the midsummer sunrise and midwinter sunset of the period. This phase of the monument was abandoned unfinished however, the small standing stones were apparently removed and the Q and R holes purposefully backfilled. Even so, the monument appears to have eclipsed the site at Avebury in importance towards the end of this phase. The Heelstone (5), a Tertiary sandstone, may also have been erected outside the north eastern entrance during this period although it cannot be securely dated and may have been installed at any time in phase 3.
    At first, a second stone, now no longer visible, joined it. Two, or possibly three, large portal stones were set up just inside the north eastern entrance of which only one, the fallen Slaughter Stone (4), 4.9 metres (16 ft) long, now remains. Other features loosely dated to phase 3 include the four Station Stones (6), two of which stood atop mounds (2 and 3). The mounds are known as 'barrows' although they do not contain burials. The Avenue, (10), a parallel pair of ditches and banks leading 3 kilometres (1.9 mi) to the River Avon was also added. Two ditches similar to Heelstone Ditch circling the Heelstone, which was by then reduced to a single monolith, were later dug around the Station Stones.
    Stonehenge 3 II (2600 BC to 2400 BC)
    The next major phase of activity saw 30 enormous Oligocene-Miocene sarsen stones (shown grey on the plan) brought to the site. They may have come from a quarry around 40 kilometres (25 mi) north of Stonehenge, on the Marlborough Downs, or they may have been collected from a "litter" of sarsens on the chalk downs, closer to hand. The stones were dressed and fashioned with mortise and tenon joints before 30 were erected as a 33 metres (110 ft) diameter circle of standing stones, with a ring of 30 lintel stones resting on top.
    The lintels were fitted to one another using another woodworking method, the tongue and groove joint. Each standing stone was around 4.1 metres (13 ft) high, 2.1 metres (6.9 ft) wide and weighed around 25 tons. Each had clearly been worked with the final effect in mind; the orthostats widen slightly towards the top in order that their perspective remains constant as they rise up from the ground while the lintel stones curve slightly to continue the circular appearance of the earlier monument.
    The sides of the stones that face inwards are smoother and more finely worked than the sides that face outwards. The average thickness of these stones is 1.1 metres (3.6 ft) and the average distance between them is 1 metre (3.3 ft). A total of 74 stones would have been needed to complete the circle and unless some of the sarsens were removed from the site, it would seem that the ring was left incomplete. Of the lintel stones, they are each around 3.2 metres (10 ft), 1 metre (3.3 ft) wide and 0.8 metres (2.6 ft) thick. The tops of the lintels are 4.9 metres (16 ft) above the ground.
    Within this circle stood five trilithons of dressed sarsen stone arranged in a horseshoe shape 13.7 metres (45 ft) across with its open end facing north east. These huge stones, ten uprights and five lintels, weigh up to 50 tons each and were again linked using complex jointing. They are arranged symmetrically; the smallest pair of trilithons were around 6 metres (20 ft) tall, the next pair a little higher and the largest, single trilithon in the south west corner would have been 7.3 metres (24 ft) tall. Only one upright from the Great Trilithon still stands; 6.7 metres (22 ft) is visible and a further 2.4 metres (7.9 ft) is below ground.

    The images of a 'dagger' and 14 'axe-heads' have been recorded carved on one of the sarsens, known as stone 53. Further axe-head carvings have been seen on the outer faces of stones known as numbers 3, 4, and 5. They are difficult to date but are morphologically similar to later Bronze Age weapons; recent laser scanning work on the carvings supports this interpretation. The pair of trilithons in north east are smallest, measuring around 6 metres (20 ft) in height and the largest is the trilithon in the south west of the horseshoe is almost 7.5 metres (25 ft) tall. This ambitious phase is radiocarbon dated to between 2600 and 2400 BC[8]. This is slightly before two sets of burials discovered 3 miles (4.8 km) to the west in Amesbury (the Amesbury Archer found in 2002, and the Boscombe Bowmen discovered in 2003) as well as the Stonehenge Archer whose body was discovered in the outer ditch of the monument in 1978.
    At a similar time a large timber circle and another avenue were constructed overlooking the River Avon 2 miles away at Durrington Walls. Opposing the solar alignments at Stonehenge, the circle was orientated towards the rising sun on the midwinter solstice, whilst the Avenue led from the river to the circle on an alignment to the setting sun on the summer solstice. Evidence of huge fires on the banks of the Avon between the two avenues also suggests that both circles were linked, and perhaps formed a procession route used on the longest and shortest days of the year. Parker Pearson speculates that the wooden circle at Durrington Walls was the centre of a 'land of the living', whilst the stone circle represented a 'land of the dead'. The Avon would have served as a journey between the two.
    Stonehenge 3 III
    Later in the Bronze Age, the bluestones appear to have been re-erected for the first time, although the exact details of this period are still unclear. They were placed within the outer sarsen circle and at this time may have been trimmed in some way. A few have timber working-style cuts in them like the sarsens themselves, suggesting they may have been linked with lintels and part of a larger structure during this phase.
    Stonehenge 3 IV (2280 BC to 1930 BC)
    This phase saw further rearrangement of the bluestones as they were placed in a circle between the two settings of sarsens and in an oval in the very centre. Some archaeologists argue that some of the bluestones in this period were part of a second group brought from Wales. All the stones were well-spaced uprights without any of the linking lintels inferred in Stonehenge 3 III. The Altar Stone may have been moved within the oval and stood vertically. Although this would seem the most impressive phase of work, Stonehenge 3 IV was rather shabbily built compared to its immediate predecessors, as the newly re-installed bluestones were not at all well founded and began to fall over. However, only minor changes were made after this phase. Stonehenge 3 IV dates from 2280 to 1930 BC.
    Stonehenge 3 V (2280 BC to 1930 BC)
    Soon afterwards, the north eastern section of the Phase 3 IV Bluestone circle was removed, creating a horseshoe-shaped setting termed the Bluestone Horseshoe. This mirrored the shape of the central sarsen Trilithons and dates from 2270 to 1930 BC. This phase is contemporary with the famous Seahenge site in Norfolk.
    After the monument (1600 BC on)
    The last known construction at Stonehenge was about 1600 BC (see 'Y and Z Holes' below), and the last known usage of it was likely during the Iron Age. Roman coins and medieval artefacts have all been found in or around the monument but it is unknown if the monument was in continuous use throughout prehistory and beyond - or exactly how it would have been used. Notable is the late 7th-6th century BC large arcing Scroll Trench which deepens E-NE towards Heelstone, and the construction of the massive Iron Age hillfort Vespasian's Camp built alongside the Avenue near the Avon. The burial of a decapitated 7th century Saxon man was excavated from Stonehenge. The site was known by scholars during the Middle Ages and since then it has been studied and adopted by numerous different groups.
    16th to 20th centuries
    Stonehenge has changed ownership on several occasions since King Henry VIII acquired Amesbury Abbey and its surrounding lands. In 1540 he gave the estate to the Earl of Hertford, and it subsequently passed to Lord Carleton and then the Marquis of Queensbury. The Antrobus family of Cheshire bought the estate in 1824, but sold it in 1915 after the last heir was killed serving in France during the First World War. The auction was held by Knight Frank & Rutley estate agents in Salisbury on the 21 September, and included "Lot 15. Stonehenge with about 30 acres, 2 rods, 37 perches of adjoining downland." Cecil Chubb bought Stonehenge for 6,600 pds. and then gave it to the nation three years later. Although it has been speculated that he purchased it at the suggestion of - or even as a present for - his wife, he in fact bought it on a whim as he believed a local man should be the new owner.
    1920s onwards
    In the late 1920s a nation-wide appeal was launched to save Stonehenge from the encroachment of modern buildings that had begun to appear around it. During World War I an aerodrome had been built on the down just west of the circle, and in the dry valley at Stonehenge Bottom a main road junction had appeared, with several cottages and a cafe. In 1928 the land around the stones was purchased with the appeal donations, and given to the National Trust in order to preserve it. The buildings were removed (although the roads were not), and the land returned to agriculture. More recently the land has been part of a grassland reversion scheme, returning the surrounding fields to native chalk grassland.
    In 2002 a public poll voted Stonehenge as one of the seven wonders of Britain, alongside Big Ben, the Eden Project, Hadrian's Wall, the London Eye, Windsor Castle, and York Minster.
    As motorised traffic increased the setting of the monument began to be affected by the proximity of the two roads on either side of it - the A344 to Shrewton on the north side, and the A303 to Winterbourne Stoke to the south. Plans to upgrade the A303 and remove it from the view of the stones have been considered since it became a World Heritage Site, but the controversy surrounding expensive re-routings of a road have led to the scheme being cancelled on multiple occasions. On 06 December 2007 it was announced that the most recent plans had been cancelled.
    Neopaganism
    Stonehenge is a place of pilgrimage for neo-druids, and for certain others following pagan or neo-pagan beliefs. The midsummer sunrise began attracting modern visitors in the 1870s, with the first record of recreated Druidic practices dating to 1905 when the Ancient Order of Druids enacted a ceremony. Despite efforts by archaeologists and historians to stress the differences between the Iron Age Druidic religion and the much older monument, Stonehenge has become increasingly, almost inextricably, associated with British Druidism, Neopaganism and New Age philosophy. Between 1972 and 1984, Stonehenge was the site of a free festival. After the Battle of the Beanfield in 1985 this use of the site was stopped for several years, and currently ritual use of Stonehenge is carefully controlled.
    Access
    When Stonehenge became open to the public it was possible to walk amongst and even climb on the stones. However this ended in 1977 when the stones were roped off as a result of serious erosion. Visitors are no longer permitted to touch the stones, but merely walk around the monument from a short distance. English Heritage does however permit access during the summer and winter solstice, and the spring and autumn equinox. Additionally, visitors can make special bookings to access the stones throughout the year.
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    • #47
      المشاركة الأصلية بواسطة ابو فيصل الحربي مشاهدة المشاركة

      Pyramids in Ireland - Newgrange




      Newgrange is not so much a pyramid as it is a large mound. It was originally built c. 3200 BC according to the most reliable Carbon 14 dates available, this makes it more than 500 years older than the Great Pyramid of Giza in Egypt, and predates Stonehenge trilithons by about 1,000 years, (the earliest stages of Stonehenge are roughly contemporary with Newgrange).
      Although it was built thousands of years ago, it lay lost for over 4,000 years due to mound slippage, until the late 17th century, when men looking for building stone uncovered it, and described it as a cave.
      Newgrange was excavated and much restored between 1962 and 1975, under the supervision of Prof Michael J O'Kelly, Dept. of Archaeology, University College, Cork. It consists of a vast man-made stone and turf mound retained within a circle 97 large kerbstones topped by a high inward-leaning wall of white quartz and granite.
      Most of the stones were sourced locally (within a radius of 20km or so) but the quartz and granite stones of the facade must have been sourced further afield, most probably in Wicklow and Dundalk bay respectively.
      Within the mound, a long passage, only going in one third of the length of the mound, leads to a cruciform (cross-shaped) chamber. The passage itself is over 60 feet (18m). The burial chamber has a corbelled roof which rises steeply upwards to a height of nearly 20 feet (6m). A tribute to its builders, the roof has remained essentially intact and waterproof for over 5,000 years.Newgrange appears to have been built as a tomb.
      The recesses in the cruciform chamber hold large stone basins into which were placed the cremated remains of those being laid to rest. During excavation, the remains of only five individuals were found. It is speculated that the sun formed an important part of the religious beliefs of the New Stone Age people who built it.
      Formerly the mound was encircled by an outer ring of immense standing stones, of which there are twelve of a possible thirty seven remaining. However, it seems that the stone circle which encirlced Newgrange are not contemporary with the monument itself but were placed there some 1,000 years later in the Bronze Age.
      Every year, at the time of the winter solstice, the sun shines directly along this passage into the chamber for about 17 minutes as it rises. The alignment with the sun is too precise to have occurred by chance.The sun however, does not enter the passage at Newgrange through the main entrance, but rather through a specially contrived opening, known as a roofbox, which lies directly above the entrance. Although solar alignments are not uncommon among passage graves, Newgrange is essentially the only one said to contain the additional roofbox feature. The solar alignment at Newgrange is also still very precise compared to similar phenomena at other passage graves such as Dowth or Maes Howe in the Orkney islands off the coast of Scotland.
      Spiral and lozenge motifs engraved on the magnificent entrance slab, "one of the most famous stones in the entire repertory of megalithic art" include a triple spiral motif, found only at Newgrange and repeated along the passage and again inside the chamber, are reminiscent of the triskelion motif of the Isle of Man, of ancient Sicily and of several passage tombs on the island of Anglesey in North Wales. There are further examples of megalithic art on many other kerbstones at Newgrange (notably Kerbstone 52 and 67). However the majority of the megalithic art in the Bru na Boinne complex is located at Newgrange's sister tomb of Knowth.
      Near Newgrange are many other passage tombs, the largest being Knowth, and another significant tomb; Dowth. These tombs are all contempory with Newgrange and together they and their 37 smaller satellite tombs form the Bru na Boinne complex.
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      • #48
        Precession of the Equinoxes



        The precession of the equinoxes refers to the precession of Earth's axis of rotation with respect to inertial space. Hipparchus discovered that the positions of the equinoxes move westward along the ecliptic compared to the fixed stars on the celestial sphere. The exact dates of his life are not known, but astronomical observations attributed to him date from 147 BC to 127 BC and were described in his publications. He is considered the greatest astronomical observer, and perhaps, the greatest overall astronomer of antiquity.
        Currently, this annual motion is about 50.3 seconds of arc per year or 1 degree every 71.6 years. The process is slow, but cumulative. A complete precession cycle covers a period of approximately 25,765 years, the so called great Platonic year, during which time the equinox regresses over a full 360°. Precessional movement also is the determining factor in the length of an Astrological Age.

        Changing Pole Stars

        Precession of Earth's axis around the north ecliptical pole

        Precession of Earth's axis around the south ecliptical pole
        A consequence of the precession is a changing pole star. Currently Polaris is extremely well-suited to mark the position of the north celestial pole, as it is about a half degree away from it and it is a moderately bright star (visual magnitude is 2.1 (variable)).
        On the other hand Thuban in the constellation Draco, which was the pole star in 3000 BC is much less conspicious at magnitude 3.67 (one-fifth as bright as Polaris); today it is all but invisible in light-polluted urban skies.
        The brilliant Vega in the constellation Lyra is often touted as the best Northstar, when it fulfilled that role around 12000 BC and will do so again around the year AD 14000.
        In reality it never comes closer than 5° to the pole.
        When Polaris will be the north star again around 27800 AD, due to its proper motion it will be farther away from the pole then than it is now, while in 23600 BC it came closer to the pole.
        To find the south celestial pole in the sky at this moment, one is less lucky, as that area is a particularly bland portion of the sky, and the nominal south pole star is Sigma Octantis, which with magnitude 5.5 is barely visible even under a properly dark sky. However that will change in the 80th to 90th century, when the south celestial pole travels through the False cross.
        It is also seen from the starmap that the south pole, nicely pointed to by the Southern cross for the last 2000 years or so, is moving towards that constellation. By consequence it is now no longer visible from subtropical northern latitudes as it was in the time of the ancient Greeks.
        Still pictures like these, found in many astronomy books, are only first approximations as they do not take into account the variable speed of the precession, the variable obliquity of the ecliptic, the planetary precession (which makes not the ecliptic pole the centre, but a circle about 6° away from it) and the proper motions of the stars.

        Polar Shift and Equinoxes Shift
        Precessional movement as seen from 'outside' the celestial sphere.
        The rotation axis of the Earth describes over a period of about 25800 years a small circle (blue) among the stars, centred around the ecliptic northpole (blue E) and with an angular radius of about 23.4°: the angle known as the obliquity of the ecliptic. The orange axis was the Earth's rotation axis 5000 years ago when it pointed to the star Thuban. The yellow axis, pointing to Polaris is the situation now. Note that when the celestial sphere is seen from outside constellations appear in mirror image. Also note that the daily rotation of the Earth around its axis is opposite to the precessional rotation. When the polar axis precesses from one direction to another, then the equatorial plane of the Earth (indicated with the circular grid around the equator) and the associated celestial equator will move too. Where the celestial equator intersects the ecliptic (red line) there are the equinoxes. As seen from the drawing, the orange grid, 5000 years ago one intersection of equator and ecliptic, the vernal equinox was close to the star Aldebaran of Taurus. By now (the yellow grid) it has shifted (red arrow) to somewhere in the constellation of Pisces. Note that this is an astronomical description of the precessional movement and the vernal equinox position in a given constellation may not imply the astrological meaning of an Age carrying the same name, as they (ages and constellations) only have an exact alignment in the "first point of Aries", meaning once in each ca. 25800 (Great Sidereal Year).


        Same picture as above but now from (near) Earth perspective It might not be directly clear to the non-astronomer what the shift of the equinoxes has to do with the precession of the rotation axis of the Earth. The figures to the right try to explain that.
        The rotation axis of the Earth describes over a period of 25700 years a small circle (blue) among the stars, centred around the ecliptic northpole (blue E) and with an angular radius of about 23.4°: the angle known as the obliquity of the ecliptic.
        The orange axis was the Earth's rotation axis 5000 years ago when it pointed to the star Thuban. The yellow axis, pointing to Polaris is the situation now. Note that when the celestial sphere is seen from outside (as in the first drawing, an impossibilty of course) constellations appear in mirror image. Also note that the daily rotation of the Earth around its axis is opposite to the precessional rotation.
        Of course when the polar axis precesses from one direction to another, then the equatorial plane of the Earth (indicated with the circular grid around the equator) and the associated celestial equator will move too. Where the celestial equator intersects the ecliptic (red line) there are the equinoxes. As seen from the drawing, the orange grid, 5000 years ago one intersection of equator and ecliptic, the vernal equinox was close to the star Aldebaran of Taurus. By now (the yellow grid) it has shifted (red arrow) to somewhere in the constellation of Pisces.
        This is why the equinoctial shift is a consequence of the precession of the rotation axis of the Earth and the other way around. The second drawing shows the perspective from a near Earth position as seen through a very wide angle lens (from which the apparent distortion).

        Explanation
        The precession as a consequence of the torque exerted on Earth by differential gravitation.
        The precession of the equinoxes is caused by the differential gravitation forces of Sun and Moon on Earth.
        In popular science books one often finds this explained with the analogy of the precession of a spinning top. Indeed it is the same physical effect, however, some crucial details differ. In a spinning top it is gravity which causes the top to wobble which in its turn causes precession. The applied force is thus in the first instance parallel to the rotation axis. But for the Earth the applied forces of the Sun and Moon are in the first instance perpendicular to it. So how then can they cause it?
        The answer is that the forces do not work on the rotation axis. Instead they work on the equatorial bulge; due to its own rotation, the Earth is not a perfect sphere but an oblate spheroid, the equatorial diameter about 43 km larger than the polar. If the Earth were a perfect sphere, there would be no precession.
        The figure explains how this works. The Earth is given as a perfect sphere (so that all gravitational forces working on it can be taken equal as one force working on its center), and the bulge is approximated to be a torus of mass (blue) around its equator.
        Green arrows indicate the gravitational forces from the Sun on some extreme points. These forces are not parallel as they all point towards the centre of the Sun. Therefore the forces working on the northernmost and southernmost parts of the equatorial bulge have a component perpendicular on the ecliptical plane and directed towards it.
        We find them (small cyan arrows) when the average gravitation force on the centre of the Earth is substracted (because this force will be used as the centripetal force for the Earth in its orbit around the Sun).
        In all cases in addition to these tangential components there will be also radial components, but they are not shown as they do not contribute to the precession (they contribute to the tides). It is now clear how these tangential forces create a torque (orange), and this torque added to the rotation (magenta) shifts the rotation axis slightly to a new position (yellow).
        Repeat this again and again, and one sees how the axis precesses along the white circle, which is centred around the ecliptic pole.
        It is important to note that the torque is always in the same direction, perpendicular onto the direction in which the rotation axis is tilted away from the ecliptic pole, so that it does not change the axial tilt itself. It is also important to note that the torque is everywhere the same, whatever position of the Earth is in its orbit around the Sun. The precession is thus always steadily progressing and does not change with the seasons.
        Although the above explanation involved the Sun, the same story holds true for any object moving around the Earth along (or close to) the ecliptic, i.e. the Moon. The combined action of the Sun and the Moon is called the lunisolar precession. In addition to the steady progressive motion (resulting in a full circle in 25700 years) the Sun and Moon also cause small periodic variations, due to their changing positions. These oscillations, in both precessional speed and axial tilt are known as the nutation. The most important term has a period of 18.6 years and an amplitude of less than 20 arcseconds.
        In addition to lunisolar precession, the actions of the other planets of the solar system cause the whole ecliptic to slowly rotate around an axis which has an ecliptic longitude of about 174° measured on the instantaneous ecliptic. This planetary precession shift is only 0.47 arcseconds per year (more than a hundred times smaller than lunisolar precession), and takes place along the instantaneous equator.
        The sum of the two precessions is known as the general precession.

        Effects of axial precession on the seasons
        This figure illustrates the effects of axial precession on the seasons, relative to perihelion and aphelion. The precession of the equinoxes can cause periodic climate change (see Milankovitch cycles), because the hemisphere that experiences summer at perihelion and winter at aphelion (as the southern hemisphere does presently) is in principle prone to more severe seasons than the opposite hemisphere.
        Hipparchus estimated Earth's precession around 130 BC, adding his own observations to those of Babylonian and Chaldean astronomers in the preceding centuries.
        In particular they measured the distance of the stars like Spica to the Moon and Sun at the time of lunar eclipses, and because he could compute the distance of the Moon and Sun from the equinox at these moments, he noticed that Spica and other stars appeared to have moved over the centuries.
        Precession causes the cycle of seasons (tropical year) to be about 20.4 minutes less than the period for the earth to return to the same position with respect to the stars as one year previously (sidereal year). This results in a slow change (one day per 71 calendar years) in the position of the sun with respect to the stars at an equinox. It is significant for calendars and their leap year rules.
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        • #49
          http://en.wikipedia.org/wiki/Dowth

          http://en.wikipedia.org/wiki/Maes_Howe
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          • #50
            http://en.wikipedia.org/wiki/Goseck_circle

            http://en.wikipedia.org/wiki/Karnak
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            • #51
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              • #52
                http://www.crystalinks.com/sirius.html
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                • #53
                  http://www.crystalinks.com/machu.html

                  Machu Picchu

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                  • #54


                    http://www.crystalinks.com/pyramidmesoamerica.html
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                    • #55





                      http://www.crystalinks.com/olmec.html
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                      • #56

                        http://www.crystalinks.com/mayancalendar.html

                        Volcanoes and UFO's








                        http://www.crystalinks.com/volcano_ufo.html
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                        • #57
                          Most ancient cultures built Astronomical Observatories - tombs, temples, cairns among others, to align with the solstices and equinoxes.

                          Stonehenge - marker of the summer and winter solstices.
                          Newgrange

                          The passage and chamber of Newgrange are illuminated by the winter solstice sunrise. A shaft of sunlight shines through the roof box over the entrance and penetrates the passage to light up the chamber. The dramatic event lasts for 17 minutes at dawn from the 19th to the 23rd of December. The light illuminates a stone basin below intricate carvings -- spirals, eye shapes, solar discs. Although not much is known about how Newgrange was used by its builders, marking the solstice was obviously of tremendous spiritual importance to them.

                          Maeshowe, on the Orkney Islands north of Scotland, shares a similar trait, admitting the winter solstice setting sun. It is hailed as one of the greatest architectural achievements of the prehistoric peoples of Scotland.
                          Hundreds of other megalithic structures throughout Europe are oriented to the solstices and the equinoxes. The blossoming field of archaeoastronomy studies such sacred sites in the Americas, Asia, Indonesia, and the Middle East.

                          Recent research into the medieval Great Zimbabwe in sub-Saharan Africa (also known as the "African Stonehenge") indicates a similar purpose.

                          In North America, one of the most famous such sites is the Sun Dagger of Chaco Canyon, New Mexico, built a thousand years ago by the Chacoans, ancestors of the Pueblo people.









                          http://www.crystalinks.com/wintersolstice.html
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                          • #58
                            Feathered Serpent Deity in Mesoamerica


                            Feathered Serpent head at the Ciudadela complex in Teotihuacan

                            Vision Serpent depicted on lintel 15 from Yaxchilan.




                            http://www.crystalinks.com/quetzalcoatl.html
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                            • #59
                              At the Ancient Ruins in West Central Idaho along the Snake River, the story of beings that came from the Stars and a Galactic War was recorded according to Indian Legend well over 30,000 years ago. The petroglyphs depict the beings that came, their interaction with the inhabitants of the ancient city, and the war and destruction that ensued. We are shown their ships which are curiously triangular in shape. Similar to those that have been recently sighted over Colorado, Arizona and California. We are also shown the portal through which the interdimensional beings came.

                              The waging of war between the Star Beings is recorded in the petroglyph to the right. The Star Beings and their counterparts, the two horned priests, are wreaking havoc upon the inhabitants of the Ancient City (represented by the smaller beings who are fleeing.)

                              This petroglyph is located on a rock adjacent to the rock shown above. It depicts the two horned Priest. It should be noted that the dumbbell shaped apparatus held in his hand may represent an archtimeter. Reference to this can be found in Alice Bailey's writings, as well as in the hieroglyphs of Egypt. These tools are said to have wielded the power of life and death.

                              This being is very similar in appearance to Quetzalcoatl who is the Deity in the fabled city of Chichen Itza in Mexico, renowned for its Mayan Pyramids. He is often depicted at the controls of an ancient airship sometimes triangular in design.


                              Star Beings emerging from triangular shaped ships

                              Possible triangular craft with retroflares
                              Figure inside - Beings Below
                              Left of the ship 4 entities - Hopi Petroglyphs

                              Possible Star Beings - Portal or UFO

                              Yei
                              The Yei are supernatural Holy People who communicate between the Navaho and their gods. They are usually shown carrying pine boughs, yucca strips and rattles in healing ceremonies. Each petroglyph is hand crafted reflecting images and messages inspired by the Ancient Ones. Native stones are carefully selected for each petroglyph with no two alike.


                              Kokopelli



                              Kiva Symbols from stone wall in the Village of the Great Kivas in New Mexico. Note the human, animal, snake and spiral figures were common to the area. Each petroglyph is hand crafted reflecting images and messages inspired by the Ancient Ones. Native stones are carefully selected for each petroglyph with no two alike.




                              Buckhorn Wash





                              Wild Horse Canyon
                              Two Males - Ascending Spirit - Two Females








                              http://www.crystalinks.com/petroglyphs.html
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                              • #60


                                http://www.crystalinks.com/anasazi.html
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