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Announced on 31 March 2010, it was expected to be completed by December 2011. The project came about after Mayor of London Boris Johnson and Olympics Minister Tessa Jowell decided in 2008 that the Olympic Park needed "something extra". Designers were asked for ideas for an "Olympic tower" at least high: Orbit was the unanimous choice from proposals considered by a nine-person advisory panel. Kapoor and Balmond believed that Orbit represented a radical advance in the architectural field of combining sculpture and structural engineering, and that it combined both stability and instability in a work that visitors can engage with and experience via an incorporated spiral walkway.
It has been both praised and criticised for its bold design, and has especially received criticism as a vanity project of questionable lasting use or merit as a public art project. The project was expected to cost £19.1 million, with £16 million coming from Britain's then-richest man, the steel tycoon Lakshmi Mittal, Chairman of the ArcelorMittal steel company, and the balance of £3.1 million coming from the London Development Agency. The name "ArcelorMittal Orbit" combines the name of Mittal's company, as chief sponsor, with Orbit, the original working title for Kapoor and Balmond's design. The ArcelorMittal Orbit temporarily closed after the 2012 Olympic and Paralympic Games while the South Plaza (in which Orbit is positioned) underwent reconstruction for its long-term legacy use as a public outdoor space.
It re-opened to the public on 5 April 2014. The structure incorporates the world's tallest and longest (178 metres) tunnel slide, designed by Carsten Höller. The idea was originally envisioned by the London Legacy Development Corporation as a way to attract more visitors to the tower. The slide includes transparent sections to give a "different perspective" of the twisting red tower and was completed in June 2016. This follows an option to abseil down the tower, introduced in 2014. History According to London mayor Boris Johnson, in around October 2008 he and Tessa Jowell decided that the site in Stratford, London that was to become the Olympic Park for the 2012 Olympics needed "something extra" to "distinguish the East London skyline", and "arouse the curiosity and wonder of Londoners and visitors".
A design competition held in 2009 called for designs for an "Olympic tower". It received about 50 submissions. Johnson has said that his early concept for the project was something more modest than Orbit, along the lines of "a kind of 21st-century Trajan's Column", but this was dropped when more daring ideas were received. The media reported unconfirmed details of the project in October 2009, describing the interest of the steel magnate Lakshmi Mittal, one of Britain's richest men, in funding a project that would cost around £15 million. Boris Johnson was believed to want something like the Eiffel Tower or the Statue of Liberty.
At that time there were understood to be five artists being considered, including Antony Gormley. Early designs reportedly included 'Transmission' by Paul Fryer, a high structure "resembling a cross between a pylon and a native American totem pole", according to The Times. A spokesman for Johnson would only confirm that he was "keen to see stunning, ambitious, world-class art in the Olympic Park", and that work on commissioning the project was at an early stage. Mittal's involvement came about after a chance meeting with Johnson in a cloakroom in Davos in January 2009, as they were on their way to separate dinner engagements.
In a conversation that reportedly lasted 45 seconds Johnson pitched the idea to Mittal, who immediately agreed to supply the steel. Mittal later said of his involvement, "I never expected that this was going to be such a huge project. I thought it was just the supply of some steel, a thousand tonnes or so, and that would be it. But then we started working with artists and I realised that the object was not just to supply steel but to complete the whole project. It took us almost 15 months of negotiation and discussion." Johnson has said that, "In reality, ArcelorMittal has given much more than the steel."
Kapoor's and Balmond's Orbit was announced as the winner on 31 March 2010. According to The Guardian, Orbit was chosen from a short list of three, beating a design by Antony Gormley and one by the architectural firm Caruso St John. According to The Times, Gormley's design was a steel colossus titled Olympian Man, a trademark piece of a statue of himself, rejected mainly on the grounds of its projected cost, estimated at £40 million. Johnson and Jowell agreed to issue a commission for Orbit in partnership with Mittal after it was chosen by a nine-person advisory panel brought together by them to advise on a long list of proposals.
According to Mittal, the panel made a unanimous decision to pick Orbit, as it both represented the Olympic Games and was achievable within the ambitious time frame. Kapoor described it as "the commission of a lifetime". Johnson pre-empted possible criticism during the official launch by stating: "Of course some people will say we are nuts – in the depths of a recession – to be building Britain’s biggest ever piece of public art. But both Tessa Jowell and I are certain that this is the right thing for the Stratford site, in Games time and beyond." The completed structure was officially unveiled to the press and public on 11 May 2012.
An image of the structure was included in the 2015 design of the British passport. The structure was re-purposed with the world's longest slide in 2016, as a way to attract more visitors. Design Interpretation According to Kapoor, the design brief from the Mayor's office was for a "tower of at least ", while Balmond said that he was told the Mayor was "looking for an icon to match the Eiffel Tower". Kapoor said that one of the influences on his design was the Tower of Babel, the sense of "building the impossible" that "has something mythic about it", and that the form "straddles Eiffel and Tatlin".
Balmond, working on the metaphor of an orbit, envisaged an electron cloud moving, to create a structure that appears unstable, propping itself up, "never centred, never quite vertical". Both believe that Orbit represents a new way of thinking, "a radical new piece of structure and architecture and art" that uses non-linearity – the use of "instabilities as stabilities." The spaces inside the structure, in between the twisting steel, are "cathedral like", according to Balmond, while according to Kapoor, the intention is that visitors will engage with the piece as they wind "up and up and in on oneself" on the spiral walkway.
The Independent described Orbit as "a continuously looping lattice ... made up of eight strands winding into each other and combined by rings like a jagged knot". The Guardian describes it as a "giant lattice tripod sporting a counterweight collar around its neck designed to offset the weight of its head, a two-storey dining and viewing gallery". According to the BBC, the design incorporates the five Olympic rings. Upon its launch Johnson said "It would have boggled the minds of the Romans. It would have boggled Gustave Eiffel." Nicholas Serota, a member of the design panel, said that Orbit was a tower with an interesting twist, with "the energy you might traditionally associate with this type of structure but in a surprisingly female form".
According to Mittal, Orbit was already the working title, as it describes continuous action, a creative representation of the "extraordinary physical and emotional effort" that Olympians undertake in their continuous drive to do better. It was decided to keep this as the final name and prepend ArcelorMittal (as the project supporter). On the public announcement of the design Johnson conceded that it might become known by something other than its official name, suggesting "Colossus of Stratford" or the "Hubble Bubble", in reference to his belief that it resembles a giant shisha pipe, or a variant on people's perceptions that it resembled a "giant treble clef", a "helter-skelter", or a "supersized mutant trombone".
Designers Orbit is described as "designed by Anish Kapoor and Cecil Balmond". Kapoor is a Turner Prize winning sculptor, while Balmond is one of the world's leading designers. According to Kapoor, both men are "interested in a place where architecture meets sculpture" and "the way that form and geometry give rise to structure". Kapoor and Balmond stated that their interests have blurred and crossed over into each other's fields since they first began working together in 2002 on Kapoor's Marsyas installation in the Turbine Hall of the Tate Modern. As well as Orbit, in 2010 Kapoor and Balmond were also working on the Tees Valley Giants, a public art project in northern England.
The sculpture was engineered by the Global engineer Arup, who developed the overall geometry, structural design and the building services including the lighting displayed extensively during the Olympic games. Architectural input by Kathryn Findlay (Ushida Findlay Architects, as a sub-consultant to Arup) made the sculpture into a functional building, for example designing the staircase. Structural The organic design of Orbit demanded an extraordinary amount of structural engineering work. This was done by Arup, which reported that it took up two-thirds of the budget for the project (twice the percentage normally allotted to structural engineering in a building project). From a structural point of view, Orbit consists of two parts: the trunk – the more-or-less vertical tower which houses the elevators and stairs and supports the observation deck.
the red tube – an open lattice of red steel that surrounds the trunk. The trunk has a base diameter of , narrowing to on the way up, then widening again to just under the observation deck. The trunk is supported and stabilized by the tube, which gives a structural character of a tripod to the entire construction. Further structural integrity is given to the construction by octagonal steel rings that surround the tube and trunk, spaced at and cross-joined pairwise by sixteen diagonally mounted steel connectors. A special part of the construction is the canopy, the conic shape that hangs off the bottom of the trunk.
Originally planned as a fibreglass composite construction, costs forced the use of steel for this section as well. Centraalstaal was approached as a special consultant for the design of the steel cone and came up with a design for a cone built out of 117 individually shaped steel panels with a total surface area of 586 square metres. The entire cone weighs 84 tonnes. Height Early contradictory reports suggested the tower would be tall. However, it finally measured in at making it the UK's tallest sculpture, surpassing the tall Aspire. The Greater London Authority on announcing the project described Orbits height in comparison with the Statue of Liberty, stating that it would be taller – the Statue of Liberty is high, including the statue and its pedestal.
The media picked up the apparent intention to cast the Orbit as London's answer to the Eiffel Tower, which is tall. The Guardian related how it was "considerably shorter", also noting that it is even " shorter than the diminutive Blackpool Tower". Its height was also compared in the media with other London landmarks. It was described as being "slightly taller" or "nearly taller" than the Big Ben clock tower, the centrepiece of the Palace of Westminster. It was also described as being "twice as tall" or "more than double the height" of Nelson's Column, the monument honouring Admiral Nelson in Trafalgar Square.
Other reports described how it was "just short of" or "almost as tall as" the Great Pyramid of Giza in Egypt, the ancient tomb of the Pharaoh Khufu. Big Ben is tall, Nelson's Column is tall, including statue and column. The Giza Pyramid was thought to have been constructed as 280 Egyptian cubits or tall, although with erosion it has reduced in height by nearly 10 metres. Construction Orbit is located in the southern area of the Olympic Park, between Olympic Stadium and the Aquatics Centre. After the March 2010 confirmation of the winning design, construction began in November 2010; it reached its full height in November 2011.
Steel is the primary material used in the sculpture. According to Balmond, there was no feasible alternative, as steel was the only material that could give the minimum thickness and maximum strength represented in the coiling structure. It was built from approximately 2000 tonnes of steel, produced as much as possible from ArcelorMittal plants, with the exact sourcing being determined by the grades of steel required and the technical requirements of the project. Of this, 60% was recycled steel produced by the Esch Belval steel plant in Luxembourg. On 14 March 2011, with construction already underway on the main pylon, The One Show broadcast footage of the on-site status of project, and profiled the four-man team putting it together, comprising two steel erectors, a crane operator and a site foreman.
Use As an observation tower, Orbit has two indoor viewing platforms on two levels, with each level having capacity for 150 people. In comparison to Orbit's 114.5-metre height, the nearby Olympic Stadium is high. According to the Greater London Authority, the observation platform offers "unparalleled views of the entire of the Olympic Park and London's skyline". According to The Independent, visitors should take the elevator to the top and descend the 455-step staircase; this should allow them to appreciate the views around which Anish Kapoor arranged the sculpture. It is expected to cope with 700 visitors per hour. During the Olympic Games the entrance fee was £15 for adults and £7 for children.
The tower does not include a dining area, however there is a cafe, shop and other facilities at the South Park Hub building, which opened in April 2014. The ambition is that the sculpture, as well as being a focal point for the Olympic Park during the Games, will form part of the wider Stratford regeneration plans, which aim to turn the Olympic site into a permanent tourist destination after the Games. Tessa Jowell said Orbit will be "like to honey to bees for the millions of tourists that visit London each year". Boris Johnson predicted it would become "the perfect iconic cultural legacy".
According to Lord Coe, chairman of the London 2012 Olympic organisers, it would play a central part in the Game's role of leaving a lasting legacy and transformed landscape in east London. During the opening ceremony of the 2012 Summer Paralympics, Joe Townsend (a Royal Marine and double amputee) delivered the Paralympic flame into Olympic Stadium via a zipline that was attached to the top of Orbit. In 2016, a permanent slide designed by German artist Carsten Höller was added to the sculpture. The slide is reported to be the world's tallest and longest tunnel slide at 178 metres. Though it was originally reported that admission to the slide would cost around £5, the general adult price for entry to the slide and orbital is currently £16.50, with additional rides costing £5 each.
Funding At the time of its public launch, the total cost of Orbit was announced as £19.1m. ArcelorMittal was to fund up to £16m, with the remaining £3.1m being provided by the London Development Agency. This consists of a £10m cash donation, and £6 million in underwriting of capital costs, which could be potentially recovered from profits generated after the Games. According to Johnson, the cost of the project would be recouped after the games through the private hire of a dining area at the top, predicting it would become a "corporate money-making venture". Mittal said he was immediately interested in Orbit after he remembered the excitement that surrounded the announcement that London had won the Olympic bid.
He saw it as an opportunity to leave a lasting legacy for London, showcase the "unique qualities of steel" and play a role in the regeneration of Stratford. Mittal said of his involvement in the project, "I live in London – I’ve lived here since 1997 – and I think it’s a wonderful city. This project is an incredible opportunity to build something really spectacular for London, for the Olympic Games and something that will play a lasting role in the legacy of the Games." Advisory panel member and director of the Tate gallery, Nicholas Serota, said Orbit was "the perfect answer to the question of how sport and art come together", and praised Mittal's "really impressive piece of patronage" for supporting a "great commission".
In October 2015 Len Duvall, a Labour member of the London Assembly, stated that the tower was losing £520,000 a year; LLDC said they had revised their visitor target from 350,000 to 150,000 per year. Reception Overall reception to Orbit was mixed, but mostly negative. With regard to its potential as a lasting visitor attraction, The Guardian's Mark Brown reflected on the mixed fortunes of other large symbolic London visitor attractions such as the popular, but loss-making, Thames Tunnel; the Skylon structure, dismantled on the orders of Winston Churchill; and the successful London Eye. When plans were first reported for an Olympic tower, the media pointed to a manifesto pledge of Johnson's to crack down on tall buildings, in order to preserve London's "precious" skyline.
The Times criticised the idea as a vanity project of Johnson's, with a design "matching his bravado", built to "seal his legacy", surmising it would be compared to other similar vanity projects such as the "wedding cake", the Monument to Vittorio Emanuele II built in Rome, or the Neutrality Arch, a rotating golden statue erected by Turkmenistan's President Saparmurat Niyazov, while comparing Johnson to Ozymandias. Art critic Brian Sewell said "Our country is littered with public art of absolutely no merit. We are entering a new period of fascist gigantism. These are monuments to egos and you couldn't find a more monumental ego than Boris."
Describing it as looking like a "catastrophic collision between two cranes", the Daily Mail reported how the structure had been immediately nicknamed the 'Eyeful Tower', as well as reflecting specific Internet comments of it being 'a rollercoaster that costs £19 million a go', or that it resembled 'twisted spaghetti', 'horrific squiggles' and 'Meccano on crack'. The Times also reported the description of it being the "Godzilla of public art". In October 2012, ArcelorMittal Orbit was nominated and made the Building Design magazine shortlist for the Carbuncle Cup—an award for the worst British building completed in the past year, which was ultimately awarded to the Cutty Sark renovation.
Jay Merrick of The Independent said that "[Orbit's] sculptural power lies in its ability to suggest an unfinished form in the process of becoming something else", describing how its artistic riskiness elevated it above the banal artworks of the public art movement that have been built elsewhere in Britain's towns and cities. Merrick was of the opinion that it would be either loved or hated, being a design which is "beautifully fractious, and not quite knowable". Jonathan Glancey of The Guardian described Orbit as "Olympian in ambition" and a "fusion between striking art and daring engineering", and said that, the Aquatics Centre apart, it represented the architecturally striking Joker in the pack, given that the rest of the landscaping and architecture for the Games "promises little to get excited about".
He believed it would become a "genuine eyecatcher" for the Olympics television coverage, with its extraordinary form being a "strange and enticing marriage of sorts" between the Eiffel Tower and the un-built early Soviet era Tatlin's Tower, with the biblical Tower of Babel as "best man". Richard Morrison of The Times described Orbit as "like an enormous wire-mesh fence that has got hopelessly snagged round the bell of a giant french horn", adding that it "seems like an awful lot of trouble just to look at East London", in comparison to a music hall comedian's refrain at the $16 million cost of the Brooklyn Bridge.
Morrison not only compared Johnson to Ozymandias, but also to the 20th century dictators Adolf Hitler, Joseph Stalin and Nicolae Ceauşescu, in their acts of "phallic politics" in building grandiose monuments. Criticising the lack of public involvement, he described how it would be an "undesired intrusion by the few into the consciousness of the many". He feared that it could become one of the many "thousands of naff eyesores" of recent public art in Britain, citing the embracing couple at St Pancras station (The Meeting Place), the Dockland's Traffic Light tree, and the proposed Rotherhithe Tunnel 'match-stick man' tribute to Isambard Kingdom Brunel, as London based examples.
Fellow Times writer Tom Dyckhoff, while calling it "a gift to the tabloids" and a "giant Mr. Messy", questioned whether the Olympic site needed another pointless icon, postulating whether it would stand the test of time like the London Eye and become a true icon to match the Eiffel Tower, or a hopeless white elephant. Suggesting the project had echoes of Tatlin's Monument to the Third International, and especially Constant Nieuwenhuys' utopian city New Babylon, he asked whether Orbit was just as revolutionary or possessed the same ideological purpose, or whether it was merely "a giant advert for one of the world’s biggest multinationals, sweetened with a bit of fun".
Rowan Moore of The Guardian questioned if it was going to be anything more than a folly, or whether it would be as eloquent as the Statue of Liberty. He speculated that the project might mark the time when society stops using large iconic projects as a tool for lifting areas out of deprivation. He questioned its ability to draw people's attention to Stratford after the Games, in a similar manner to the successes of the Angel of the North or the Guggenheim Museum Bilbao. He also questioned the piece's ability to strike a chord like the Angel, which he believed had at least "created a feelgood factor and sense of pride" in Gateshead, or whether it would simply become one of the "many more unloved rotting wrecks that no one has the nerve to demolish".
He postulated that the addition of stairs and a lift made Orbit less succinct than Kapoor's previous successful works, while ultimately he said "hard to see what the big idea is, beyond the idea of making something big". Fellow Guardian writer John Graham-Cumming rejected comparisons to icons like the Eiffel Tower, which had itself not been intended to be a lasting monument, only persisting into public acceptance as art through being useful; he also pointed out the Colossus of Rhodes collapsed within a few decades, and the Tower of Babel was "constructed to glorify those that constructed it." He suggested that Johnson should reconsider whether it should be pulled down after 20 years.
Questioning its corporate role, he believed that meant it looked less and less like a work of art and more like a vanity project. In an online poll published by The Guardian, 38.6% of readers considered it a "grand design", while 61.4% for considered it "garbage". Responding to concerns from The Times that ArcelorMittal's sponsorship and naming of Orbit would represent an improper incursion of corporate branding into public life, Johnson stated that Olympic rules mean that it cannot carry any corporate branding during the games. Felicity Carus of The Guardian's environment blog questioned whether ArcelorMittal's record on carbon emissions was good enough to mean Orbit represented a fitting monument for the 2012 Olympics, billed as a 'world's first sustainable Olympics'.
Advisory panel The advisory panel consisted of: Nicholas Serota, director of the Tate gallery Julia Peyton-Jones, director of the Serpentine Gallery Hans-Ulrich Obrist, also of the Serpentine Gallery Sarah Weir OBE, of the Olympic Delivery Authority Stuart Lipton, of Chelsfield LLP Anita Zabludowicz, of the 176 gallery Zabludowicz collection Michael Morris and James Lingwood, directors of the Artangel arts commissioning organisation Munira Mirza, the Mayoral Advisor on Arts and Culture In announcing the winning design, Johnson thanked the Greater London Authority, the Olympic Delivery Authority and the London Organising Committee of the Olympic Games and Paralympic Games, as well as David McAlpine and Philip Dilley of Arup, and Sir Robin Wales and Jules Pipe for their involvement and support in the project.
See also B of the Bang, the 2002 Manchester Commonwealth Games sculpture Skylon, the London 1951 Festival of Britain tower The White Horse at Ebbsfleet, a proposed giant sculpture for Kent Googie architecture, earlier space-inspired architecture Unisphere, constructed by competitor United States Steel for the 1964 New York World's Fair Footnotes References External links Orbit Anish Kapoor website The ArcelorMittal Orbit Greater London Authority 360 degree view of the Orbit London Mayor's YouTube channel Category:2012 establishments in England Category:2012 sculptures Category:Towers completed in 2012 Category:Observation towers in the United Kingdom Category:Towers in London Category:Buildings and structures in the London Borough of Newham Category:Tourist attractions in the London Borough of Newham Category:Steel sculptures in England Category:Stratford, London Category:Queen Elizabeth Olympic Park Category:Outdoor sculptures in London Category:ArcelorMittal Category:Sculptures by Anish Kapoor
The Hobart class is a ship class of three air warfare destroyers (AWDs) being built for the Royal Australian Navy (RAN). Planning for ships to replace the Adelaide-class frigates and restore the capability last exhibited by the Perth-class destroyers began by 2000, initially under acquisition project SEA 1400, which was re-designated SEA 4000. Although the designation "Air Warfare Destroyer" is used to describe ships dedicated to the defence of a naval force (plus assets ashore) from aircraft and missile attack, the planned Australian destroyers are expected to also operate in anti-surface, anti-submarine, and naval gunfire support roles. Planning for the Australian Air Warfare Destroyer (as the class was known until 2006) continued through the mid-2000s, with the selection of the Aegis combat system as the intended combat system and ASC as the primary shipbuilder in 2005.
In late 2005, the AWD Alliance was formed as a consortium of the Defence Materiel Organisation (DMO), ASC, and Raytheon. Between 2005 and 2007, Gibbs & Cox's Evolved Arleigh Burke-class destroyer concept and Navantia's Álvaro de Bazán-class frigate competed for selection as the AWD design. Although the Arleigh Burke design was larger and more capable, the Álvaro de Bazán design was selected in June 2007 as it was an existing design, and would be cheaper, quicker, and less risky to build. Three ships were ordered in October 2007, and will be assembled at ASC's facility in Osborne, South Australia, from 31 pre-fabricated modules (or 'blocks').
An option to build a fourth destroyer was included in the original contract, but has not been exercised. ASC, NQEA Australia, and the Forgacs Group were selected in May 2009 to build the blocks, but within two months, NQEA was replaced by BAE Systems Australia. Construction errors and growing delays led the AWD Alliance to redistribute the construction workload in 2011, with some modules to be built by Navantia. Increasing slippage has pushed the original planned 2014-2016 commissioning dates out by at least three years, with lead ship to be completed by June 2017, in September 2018, and by March 2020.
The AWD Alliance, Navantia, and the involved shipyards have been criticised for underestimating risks, costs, and timeframes; faulty drawings and bad building practices leading to repeated manufacturing errors; and blame-passing. The alliance concept has been panned for having no clear management structure or entity in charge, and having the DMO simultaneously acting as supplier, build partner, and customer for the ships. Planning The 1992 Force Structure Review contained plans to replace the three Perth-class guided-missile destroyers and four of the six Adelaide-class guided-missile frigates with air defence vessels. The initial proposal – to build an additional six Anzac-class frigates configured for wide-area anti-aircraft warfare – did not go ahead as the Anzac design was too small to effectively host all the required equipment and weapons.
Instead, the RAN began to upgrade the Adelaides in 1999 to fill the anti-aircraft capability that would be lost when the Perths left service between 1999 and 2001. The frigate upgrade was only intended as a stop-gap (only four ships were upgraded, and all four were due to decommission during the mid-2010s), and by 2000, the Australian Defence Force had begun a project to replace the three Perth-class destroyers. The acquisition of the dedicated air warfare destroyers was initially identified as Project SEA 1400, then redesignated Project SEA 4000. The main role of the air warfare destroyer is air defence of a naval task group, in addition to assets ashore and operating in the littoral.
Although specifically designed for air warfare, the AWDs also had to be capable of facing other threats, and were to be fitted with ship-to-ship missiles, a gun for naval gunfire support of soldiers ashore, and anti-submarine capability through sonar systems and abovewater-launched torpedoes. The ships had to be able to operate a helicopter for both surveillance and combat duties. In 2004, the Department of Defence identified that the future air warfare destroyer class would be built around the United States Navy's Aegis Combat System. The use of Aegis was formally approved in April 2005, and Raytheon Australia was brought into the AWD project with the responsibility of integrating the Aegis system into the selected design, along with modifications to accommodate RAN-preferred electronic warfare equipment, underwater sensors, and weapons.
In May 2005, the ASC shipyard at Osborne, South Australia, was identified as the primary shipbuilder for the project. In late 2005, the AWD Alliance was formed to organise and implement the project. The Alliance is a consortium including the Defence Materiel Organisation (DMO), ASC's project-dedicated subsidiary, and Raytheon. After receiving tenders from Blohm + Voss, Navantia, and Gibbs & Cox, among others, the Australian government identified Gibbs & Cox's Evolved Flight II Arleigh Burke-class destroyer as the preferred design in August 2005. The Álvaro de Bazán-class frigate, designed by Navantia, was identified as the official alternative, and both designs began further testing and modification as part of a two-year selection process.
The two ship designs were equivalent in many areas, including length, speed and weapons outfit, although the Arleigh Burke class was larger with a displacement 2,200 tons greater than the Spanish frigate, and had superior capabilities in regards to range ( greater), helicopter operations (two embarked helicopters instead of one), primary armament (a 64-cell Mark 41 Vertical Launch System compared to a 48-cell launcher), and close-defence (with a second close-in weapons system). The Chief of Navy, Vice Admiral Russ Shalders, believed the American design would provide the RAN with a greater long-term capability, as there was greater scope for upgrades and modifications later in the ships' careers.
Despite the American destroyer being the preferred option, the conclusion of the selection process in late June 2007 saw Navantia's Álvaro de Bazán design selected: the Spanish ships were considered a less-risky design as, unlike the Evolved Arleigh Burkes (which at this point only existed as an on-paper design), vessels of the Spanish design had been built and were operational. The Álvaro de Bazán derivatives were predicted to be in service four years earlier than the American-designed ships, and would cost A$1 billion less to build, with further financial and technical benefits in ordering the AWDs and the Canberra-class landing helicopter dock ships from the same supplier.
The contract for the ships was signed on 4 October 2007. The A$8 billion, three-ship deal included the option to order a fourth ship at a later date. This option was due to expire in October 2008. The Australian government sought to extend the offer into early 2009, so as to review the recommendations of the Defending Australia in the Asia Pacific Century: Force 2030 white paper due for completion at the end of 2008, and to enquire about acquiring a fourth Aegis system from the USN, before ordering or cancelling the fourth destroyer. The Navy League of Australia has consistently supported the acquisition of a fourth AWD.
According to the Navy League, building a fourth destroyer would be relatively cheap (money for design and other 'start-up' costs would have already been spent) and improve RAN capabilities (by offering increased flexibility and redundancy, particularly in the event of a Falklands War-like armed conflict). Along with the Navy League, the Australian defence industry has supported a fourth destroyer, to keep workers employed for longer while reducing the gap to the next major defence construction projects (the Collins-class replacement and the Anzac-class replacement). The Australian Minister for Defence announced on 20 January 2006 that the Air Warfare Destroyers will be named , , and .
The Navy League of Australia suggested several possible names for a possible fourth destroyer; one was to name the ship Melbourne; another involved taking the Adelaide name from the second Canberra-class landing helicopter dock ship, and renaming the larger vessel Australia. Design Each destroyer will have a length overall of , a maximum beam of , and a draught of . At launch, the ships will have a full-load displacement of . The Hobarts have been designed to allow for upgrades and installation of new equipment, with a theoretical maximum displacement of . The Hobarts use a more powerful propulsion system than their Spanish predecessors.
The combined diesel or gas turbine (CODOG) propulsion arrangement consists of two General Electric Marine model 7LM2500-SA-MLG38 gas turbines, each generating , and two Caterpillar Bravo 16 V Bravo diesel engines, each providing . These drive two propeller shafts, fitted with Wärtsilä controllable pitch propellers. The ships' maximum speed is over , with a range of over at ; although not fast enough to keep pace with an American carrier battle group, the RAN is happy with the speed/range tradeoff, as endurance is more important for Australian operating conditions. For in-harbour manoeuvring, each destroyer is fitted with a bow thruster.
The standard ship's company is 186-strong, plus 16 additional personnel to operate and maintain the ship's helicopter. Additional accommodation increases the maximum potential complement to 31 officers and 203 sailors. Onboard electricity requirements (the hotel load) are supplied by four MTU prime mover diesel motors connected to Alconza alternators. Armament Each ship's main weapon is a 48-cell Mark 41 Vertical Launch System. The cells are capable of firing the RIM-66 Standard 2 anti-aircraft missile or the quad-packed RIM-162 Evolved Sea Sparrow point-defence missile. The Force 2030 white paper indicates that the Hobarts Mark 41 launchers are likely to be capable (either as built or through later modification) of firing the RIM-174 Standard 6 anti-aircraft missile and the Tomahawk cruise missile.
The missiles are supplemented by two four-canister launchers for Harpoon anti-ship missiles, and a BAE Systems Mark 45 (Mod 4) 5-inch gun with a 62-calibre barrel. The 5-inch gun has a maximum range of . Two Babcock Mark 32 Mod 9 two-tube torpedo launchers will be carried, and used to fire Eurotorp MU90 torpedoes at submarines. For close-in defence, the ships will carry an aft-facing Phalanx CIWS system, plus two M242 Bushmasters in Typhoon mounts sited on the bridge wings. In November 2006, the Australian Government commissioned research on whether the AWDs should be equipped with anti-ballistic missile capabilities, most likely linked to the United States Department of Defense's Aegis Ballistic Missile Defense System.
The Hobarts will each initially carry a single S-70B-2 Seahawk helicopter. The helicopter will be replaced by the MH-60 Romeo version of the Seahawk once it enters RAN service. Two rigid-hulled inflatable boats are carried. Sensors and systems The Hobarts are built around the Aegis combat system, specifically the Aegis Baseline 7.1 Refresh 2 version. The system has been 'Australianised' to be more capable in regards to non-aviation threats. The system feeds into the Australian Tactical Interface; six multi-function consoles that are capable of handling the destroyer's sonar, electronic warfare, and close-defence functions in addition to Aegis. The main radar system is the Lockheed Martin AN/SPY-1D(V) S-band radar.
The combination of the AN/SPY-1D(V) radar, Aegis system, and Standard 2 missile will allow each destroyer to fire on enemy aircraft or missiles over away. In addition to the main radar, the Hobarts will be fitted with a Northrop Grumman AN/SPQ-9B X-band pulse Doppler horizon search radar, a Raytheon Mark 99 fire-control system with two continuous wave illuminating radars for missile direction, and two L-3 Communications SAM Electronics X-band navigation radars. The ships are fitted with an Ultra Electronics Sonar Systems' Integrated Sonar System, which includes a hull-mounted sonar and a towed variable depth sonar built up from a quad directional active-passive receive array, a passive torpedo detection array and a high-powered towed sonar source.
Other sensors include an Ultra Electronics Series 2500 electro-optical director, a Sagem VAMPIR IR search and track system, and Rafael Toplite stabilised target acquisition sights for each ship's Typhoons. Electronic warfare sensors consist of the ITT EDO Reconnaissance and Surveillance Systems ES-3701 electronic support measures (ESM) radar, a SwRI MBS-567A communications ESM system, an Ultra Electronics Avalon Systems multipurpose digital receiver, and a Jenkins Engineering Defence Systems low-band receiver. Countermeasures include four launchers for Nulka decoy missiles, plus four six-tube launchers for radio frequency, infrared, and underwater acoustic decoys. Communications equipment includes HF, VHF, and UHF radios, Link 11 and Link 16 tactical data exchange uplinks, ASTIS MCE (Advanced SATCOM Terrestrial Infrastructure System Maritime Communications Elements) terminals, and Inmarsat equipment.
Control System The control system for this class is provided by Navantia and is a version of the Integrated Platform Management System (IPMS) designed specifically for the Hobart Class Destroyers. The implementation of Navantia’s IPMS uses COMPLEX / SIMPLEX, a framework developed by Navantia for new ship builds and all future modernisations. This system allows for the automation, control and supervision of all the equipment that is installed on the ship with the exception of the combat system. Currently within the Royal Australian Navy (RAN) the IPMS is installed on the Canberra-class landing helicopter dock, Hobart Class guided missile destroyers and the Supply-class replenishment oiler platforms as well as on-board more than 60 ships across multiple navies.
Construction Each ship is assembled from 31 pre-fabricated modules or 'blocks', averaging in weight and in size. The nine blocks making up the forward superstructure of each destroyer, containing the most sensitive or classified equipment, are manufactured by ASC's shipyard at Osborne, South Australia, where the final assembly of each destroyer will occur. The other 22 blocks for each ship were subcontracted out. On 9 May 2009, two companies were selected to fabricate the additional blocks: NQEA Australia (building the twelve blocks of each ship's hull) and Forgacs Group (building the ten aft superstructure blocks per ship). However, during June, NQEA advised the AWD Alliance that the shipbuilder was undergoing restructuring and may have difficulty in meeting its contracted obligations.
The Department of Defence went into negotiations with NQEA and BAE Systems Australia (which had been shortlisted during the initial subcontractor selection process), and at the end of June, transferred all of NQEA's work to BAE. In October 2010, the central keel block manufactured by BAE for Hobart was found to be distorted and incompatible with other hull sections. The cause of the fabrication errors is unknown: BAE blamed incorrect drawings from designer Navantia, while the AWD Alliance claimed the other two shipyards have not experienced similar problems, when in fact they had, and suggested first-of-kind manufacturing errors were made by BAE.
However, a report in 2014, by the Australian National Audit Office (ANAO) confirmed that 'errors resulting from a sub-standard technology transfer procedure (passing on specific techniques relative to the design) & drawings that were not localised by designer Navantia' were to blame. The delay in reworking the keel block was predicted to set construction back by at least six months. Other major issues during Hobarts construction included the need to replace 25% of the internal pipework due to faulty manufacture, and the initial rejection of the ship's mainmast block because of defects in the cabling and combat system equipment. Brisbanes construction has been marred by numerous defects requiring rework.
In late May 2011, the government announced that the delay in building Hobart had increased to between one and two years, and would attempt to reduce the workload on BAE (which is also responsible for superstructure work on the Canberra-class amphibious ships) by redistributing up to 13 of the 24 hull blocks the company was slated to build for the first two ships to the other two shipyards. In addition, the three blocks containing each destroyer's hull-mounted sonar are being assembled by Navantia in Spain and the United Kingdom, with the possibility another two hull blocks could be assigned to the Spanish shipyard.
An additional nine-month delay was announced in September 2012; this was intended to create a better transition of labour from the destroyers to following shipbuilding projects (replacements for the Collins-class submarines and the Anzac-class frigates), and achieve some savings in the federal budget. A March 2014 report by the ANAO heavily criticised the DMO and the AWD Alliance for underestimating the risks in redesigning the ships for Australian operations, and building them in shipyards with no recent warship construction experience. The ANAO report also criticised designer Navantia and the shipyards involved in block construction over poor drawings, repeated errors, and bad building practices.
As a result of further delays and growing costs, the Hobart-class destroyer project was added to the government's "Projects of Concern" list in June 2014. Follow-up government reports identified unrealistic time and cost estimates as additional factors. The overarching alliance concept has been repeatedly denounced, with no effective management structure or entity in charge, (allowing for repeated blame-passing between the individual alliance partners, Navantia, and the subcontracted shipyards), and the DMO locked in a contradictory role (simultaneously acting as supplier, build partner, and customer). Hobarts keel was laid down on 6 September 2012, and the ship was launched on 23 May 2015, with 76% of construction complete.
Brisbane was laid down on 3 February 2014, and by October 2015 was 68% complete.<ref>Australian Associated Press, 'Adelaide keel ceremony for destroyer</ref> Sydney was laid down on 19 November 2015 (two weeks after the Adelaide-class frigate of the name was decommissioned, and on the anniversary of the loss of the second Sydney during World War II), with block fabrication due to complete in early 2016. Originally, the Hobart-class destroyers were to be operational between December 2014 and June 2017. In September 2012, the ongoing delays prompted revision of the entry-to-service dates to March 2016, September 2017, and March 2019. In May 2015, the DMO announced additional schedule slippage, with Hobart to be handed over to the RAN in June 2017, Brisbane due in September 2018, and Sydney by December 2019.McPhedran, Destroyer project now three years behind schedule The original contract cost was A$8 billion for the three ships.
By March 2014, the project was running A$302 million over budget. By May 2015, this had increased to A$800 million, with a predicted minimum cost overrun by project end of A$1.2 billion. In February 2018, the Hobart-class was removed from the "Projects of Concern" list, after long-term reform arrangements were put in place. In May 2018, the third and final Hobart-class ship, Sydney'', was launched. Ships See also Aegis Combat System List of naval ship classes in service List of active Royal Australian Navy ships Citations References Journal articles News articles Press releases Websites External links Royal Australian Navy DDG Defence Materiel Organisation – SEA 4000 Air Warfare Destroyer Air Warfare Destroyer Alliance Category:Destroyer classes
A paragon is a perfect diamond — flawless and without inclusions. In the 16th century, a mass of was sufficient to qualify for this designation, but today the threshold lies at . The largest flawless diamond in the world is known as The Paragon, a D-color gem weighing , and the tenth largest white diamond in the world. The gem was mined in Brazil and attracted attention for being an exceptional white, flawless stone of great size. The Mayfair-based jeweller Graff Diamonds acquired the stone in Antwerp, cut it into an unusual seven-sided kite shield configuration, and set it in a necklace which separates to both necklace and bracelet lengths.
Apart from the main stone, this necklace also contains rare pink, blue, and yellow diamonds, making a total mass of . The necklace has associations with the end of the millennium and was worn by model Naomi Campbell at a diamond gala held by De Beers and Versace at Syon House in 1999. References External links entry at The World of Famous Diamonds Category:Individual diamonds Category:Individual necklaces Category:Diamonds originating in Brazil
The hypoglossal canal is a foramen in the occipital bone of the skull. It is hidden medially and superiorly to each occipital condyle. The hypoglossal nerve traverses the canal. Structure It transmits the hypoglossal nerve from its point of entry near the medulla oblongata to its exit from the base of the skull near the jugular foramen. It lies in the epiphyseal junction between the basiocciput and the jugular process of the occipital bone. Function The hypoglossal canal has recently been used to try to determine the antiquity of human speech. Researchers have found that hominids who lived as long as 2 million years ago had the same size canal as that of modern-day chimpanzees; some scientists thus assume they were incapable of speech.
However, archaic H. sapiens 400,000 years ago had the same size canal as that of modern humans, meaning they could have been capable of speech. Some Neanderthals also had the same size hypoglossal canal as archaic H. sapiens. However recent studies involving several primate species have failed to find conclusive evidence of a relationship between its size and speech. Clinical significance The hypoglossal canal is formed during the embryological stage of development in mammals, sometimes leading to the presence of more than two canals as the occipital bone is formed. Study of this area aids in the diagnosis of a variety of tumors found at the base of the skull, including: large glomus jugulare neoplasms, myelomas, and the occasional meningioma.
Studies of the hypoglossal canal revolve around the development of safe drilling techniques to conduct surgery on that area of the brain. Additional images See also References External links () Image at uwo.ca Category:Foramina of the skull
A zone plate is a device used to focus light or other things exhibiting wave character. Unlike lenses or curved mirrors however, zone plates use diffraction instead of refraction or reflection. Based on analysis by Augustin-Jean Fresnel, they are sometimes called Fresnel zone plates in his honor. The zone plate's focusing ability is an extension of the Arago spot phenomenon caused by diffraction from an opaque disc. A zone plate consists of a set of radially symmetric rings, known as Fresnel zones, which alternate between opaque and transparent. Light hitting the zone plate will diffract around the opaque zones. The zones can be spaced so that the diffracted light constructively interferes at the desired focus, creating an image there.
Design and manufacture To get constructive interference at the focus, the zones should switch from opaque to transparent at radii where where n is an integer, λ is the wavelength of the light the zone plate is meant to focus and f is the distance from the center of the zone plate to the focus. When the zone plate is small compared to the focal length, this can be approximated as . For plates with many zones, you can calculate the distance to the focus if you only know the radius of the outermost zone, rN, and its width, ΔrN: In the long focal length limit, the area of each zone is equal, because the width of the zones must decrease farther from the center.
The maximum possible resolution of a zone plate depends on the smallest zone width, Because of this, the smallest size object you can image, Δl, is limited by how small you can reliably make your zones. Zone plates are frequently manufactured using lithography. As lithography technology improves and the size of features that can be manufactured decreases, the possible resolution of zone plates manufactured with this technique can improve. Continuous zone plates Unlike a standard lens, a binary zone plate produces intensity maxima along the axis of the plate at odd fractions (f/3, f/5, f/7, etc.). Although these contain less energy (counts of the spot) than the principal focus (because it is wider), they have the same maximum intensity (counts/m).
However, if the zone plate is constructed so that the opacity varies in a gradual, sinusoidal manner, the resulting diffraction causes only a single focal point to be formed. This type of zone plate pattern is the equivalent of a transmission hologram of a converging lens. For a smooth zone plate, the opacity (or transparency) at a point can be given by: where is the distance from the plate center, and determines the plate's scale. Binary zone plates use almost the same formula, however they depend only on the sign: Free parameter It does not matter to the constructive interference what the absolute phase is, but only that it is the same from each ring.
So an arbitrary length can be added to all the paths This reference phase can be chosen to optimize secondary properties such as side lobes. Applications Physics There are many wavelengths of light outside of the visible area of the electromagnetic spectrum where traditional lens materials like glass are not transparent, and so lenses are more difficult to manufacture. Likewise, there are many wavelengths for which there are no materials with a refractive index significantly larger than one. X-rays, for example, are only weakly refracted by glass or other materials, and so require a different technique for focusing. Zone plates eliminate the need for finding transparent, refractive, easy-to-manufacture materials for every region of the spectrum.
The same zone plate will focus light of many wavelengths to different foci, which means they can also be used to filter out unwanted wavelengths while focusing the light of interest. Other waves such as sound waves and, due to quantum mechanics, matter waves can be focused in the same way. Wave plates have been used to focus beams of neutrons and helium atoms. Photography Zone plates are also used in photography in place of a lens or pinhole for a glowing, soft-focus image. One advantage over pinholes (aside from the unique, fuzzy look achieved with zone plates) is that the transparent area is larger than that of a comparable pinhole.
The result is that the effective f-number of a zone plate is lower than for the corresponding pinhole and the exposure time can be decreased. Common f-numbers for a pinhole camera range from to or higher, whereas zone plates are frequently and lower. This makes hand held shots feasible at the higher ISO settings available with newer DSLR cameras. Gunsights Zone plates have been proposed as a cheap alternative to more expensive optical sights or targeting lasers. Lenses Zone plates may be used as imaging lenses with a single focus as long as the type of grating used is sinusoidal in nature.
Reflection A zone plate used as a reflector will allow radio waves to be focused as if by a parabolic reflector. This allows the reflector to be flat, and so easier to make. It also allows an appropriately patterned Fresnel reflector to be mounted flush to the side of a building, avoiding the wind loading that a parabaloid would be subject to. Software testing A bitmap representation of a zone plate image may be used for testing various image processing algorithms, such as: Image interpolation and image resampling; Image filtering. An open-source zone-plate image generator is available. See also Arago spot Diffraction grating Fresnel imager Fresnel lens Fresnel number Fresnel zone antenna Photon sieve References External links Magnetic Soft X-ray microscopy Making a photographic zone plate Whiz Kid Technomagic Zone Plate Designer Examples of zone plate photographs Category:Optical components Category:Photography equipment
Chöd ( lit. 'to sever'), is a spiritual practice found primarily in the Yundrung Bön tradition as well as in the Nyingma and Kagyu schools of Tibetan Buddhism (where it is classed as Anuttarayoga Tantra). Also known as "Cutting Through the Ego,", the practices are based on the Prajñāpāramitā or "Perfection of Wisdom" sutras, which expound the "emptiness" concept of Buddhist philosophy. According to Mahayana Buddhists, emptiness is the ultimate wisdom of understanding that all things lack inherent existence. Chöd combines prajñāpāramitā philosophy with specific meditation methods and tantric ritual. The chod practitioner seeks to tap the power of fear through activities such as rituals set in graveyards, and visualisation of offering their bodies in a tantric feast in order to put their understanding of emptiness to the ultimate test.
Nomenclature, orthography and etymology and Sanskrit chedasādhanā both literally mean "cutting practice". In Standard Tibetan (the prestige dialect associated with Buddhism that is based on the speech of Lhasa), the pronunciation of gcod is IPA //. Key elements of the practice Chöd literally means "cutting through". It cuts through hindrances and obscurations, sometimes called 'demons' or 'gods'. Examples of demons are ignorance, anger and, in particular, the dualism of perceiving the self as inherently meaningful, contrary to the Buddhist doctrine of anatta (non-self). This is done in a powerful meditative ritual which includes "a stunning array of visualizations, song, music, and prayer, it engages every aspect of one’s being and effects a powerful transformation of the interior landscape."
According to Jamgön Kongtrül, Chöd involves "accepting willingly what is undesirable, throwing oneself defiantly into unpleasant circumstances, realising that gods and demons are one’s own mind, and ruthlessly severing self-centered arrogance through an understanding of the sameness of self and others." According to Machig Labdrön, the main goal of Chöd is cutting through ego clinging: Dzogchen forms of Chöd enable the practitioner to maintain rigpa, primordial awareness free from fear. Here, the Chöd ritual essentialises elements of phowa, gaṇacakra, pāramitā and lojong pure illusory body, mandala, brahmavihāra, luminous mind, and tonglen. Chöd usually commences with phowa, in which the practitioner visualises their mindstream as the Five Pure Lights leaving the body through the aperture of the sahasrara at the top of the head.
This is said to ensure psychic integrity of, and compassion for the sādhaka or practitioner. In most versions of the sādhanā, the mindstream precipitates into a tulpa simulacrum of Vajrayoginī. In saṃbhogakāya attained through visualization, the sādhaka offers a gaṇachakra of their own physical body to the "four" guests: the Three Jewels, dakinis, dharmapalas and beings of the bhavachakra, the ever-present lokapala and the pretas. The rite may be protracted with separate offerings to each maṇḍala of guests, or significantly abridged. Many versions of the chod sādhana still exist. Chöd, like all tantric systems, has outer, inner and secret aspects.
They are described in an evocation sung to Nyama Paldabum by Milarepa: Chöd is now a staple of the advanced sādhana of Tibetan Buddhism. It is practiced worldwide following dissemination by the Tibetan diaspora. Vajrayogini is a key figure in the advanced practice of Chöd, where she appears in her Kālikā () or Vajravārāhī () forms. The practices of Tröma Nagmo "Extremely Wrathful Black Mother" associated with the Dakini Tröma Nagmo (the black form of Vajrayogini) were also propagated by Machig Labdrön. "The particular transmission which His Holiness will give descends from Dudjom Lingpa, who received it in a direct vision of the Indian Mahasiddha, Saraha.
This practice emphasizes cutting through grasping at the dualistic mind to realize complete selfless compassion. One of the forms of this style of Chöd can be found in the Dudjom Tersar lineage. Indian antecedents "Chöd was never a unique, monolithic tradition. One should really speak of Chöd traditions and lineages since Chöd has never constituted a school." A form of Chöd was practiced in India by Buddhist mahāsiddhas prior to the 10th century. The two practices of Chöd in Buddhism and in Bön are distinct lineages. There are two main Chöd traditions within Buddhism, the "Mother" and "Father" lineages. Dampa Sangye is known as the "Father of Chöd" and Machig Labdrön, founder of the Mahamudra Chöd lineages, as the "Mother of Chöd".
Bön traces the origin of Chöd to the Secret Mother Tantra, the seventh of the Nine Vehicles of Bön practice. There are four distinct styles of Chöd practice. Chöd developed outside the monastic system. It was subsequently adopted by the monastic lineages. As an internalization of an outer ritual, Chöd involves a form of self-sacrifice: the practitioner visualizes their own body as the offering at a ganachakra. The purpose of the practice is to engender a sense of victory and fearlessness. These two qualities are represented iconographically by the victory banner and the ritual knife. The banner symbolizes overcoming obstacles and the knife symbolizes cutting through the ego.
The practitioner may cultivate imaginary fearful or painful situations since they help the practitioner's work of cutting through attachment to the self. Machig Labdrön said, "To consider adversity as a friend is the instruction of Chöd". Chödpa as 'mad saints' Sarat Chandra Das, writing at the turn of the 20th Century, equated the Chöd practitioner () with the Indian avadhūta, or "mad saint". Avadhūtas - called nyönpa in Tibetan Buddhism - are renowned for expressing their spiritual understanding through "crazy wisdom" inexplicable to ordinary people. Chöd practitioners are a type of Mad Saint particularly respected, feared or held in awe due to their roles as denizens of the charnel ground.
According to tibetologist Jérôme Édou, Chod practitioners were often associated with the role of shaman and exorcist: Iconography In Chöd, the adept symbolically offers the flesh of their body in a form of gaṇacakra or tantric feast. Iconographically, the skin of the practitioner's body may represent surface reality or maya. It is cut from bones that represent the true reality of the mindstream. Commentators have pointed out the similarities between the Chöd ritual and the prototypical initiation of a shaman, although one writer identifies an essential difference between the two in that the shaman's initiation is involuntary whilst a Chodpa chooses to undertake the ritual death of a Chod ceremony.
Traditionally, Chöd is regarded as challenging, potentially dangerous and inappropriate for some practitioners. Ritual objects Practitioners of the Chöd ritual, Chödpa, use a kangling or human thighbone trumpet, and a Chöd drum, a hand drum similar to but larger than the ḍamaru commonly used in Tibetan ritual. In a version of the Chöd sādhanā of Jigme Lingpa from the Longchen Nyingthig, five ritual knives are employed to demarcate the maṇḍala of the offering and to affix the five wisdoms. Key to the iconography of Chöd is the (), a half-moon blade knife for skinning an animal and for scraping hides.
The practitioner symbolically uses a kartika to separate the bodymind from the mindstream in ritual. Kartika imagery in Chöd rituals provides the practitioner with an opportunity to realize Buddhist doctrine: Origins of the practice Some sources have described Machig Labdrön as the founder of the practice of Chöd. This is accurate in that she is the founder of the Tibetan Buddhist Mahamudrā Chöd lineages. Machig Labdrön is credited with providing the name "Chöd" and developing unique approaches to the practice. Biographies suggest it was transmitted to her via sources of the mahāsiddha and tantric traditions. She did not found the Dzogchen lineages, although they do recognize her, and she does not appear at all in the Bön Chöd lineages.
Among the formative influences on Mahamudrā Chöd was Dampa Sangye's Pacification of Suffering (). The transmission of Chöd to Tibet There are several hagiographic accounts of how Chöd came to Tibet. One namtar (spiritual biography) asserts that shortly after Kamalaśīla won his famous debate with Moheyan as to whether Tibet should adopt the "sudden" route to enlightenment or his "gradual" route, Kamalaśīla used the technique of phowa to transfer his mindstream to animate a corpse polluted with contagion in order to safely move the hazard it presented. As the mindstream of Kamalaśīla was otherwise engaged, a mahasiddha by the name of Dampa Sangye came across the vacant "physical basis" of Kamalaśīla.
Padampa Sangye, was not karmically blessed with an aesthetic corporeal form, and upon finding the very handsome and healthy empty body of Kamalaśīla, which he assumed to be a newly dead fresh corpse, used phowa to transfer his own mindstream into Kamalaśīla's body. Padampa Sangye's mindstream in Kamalaśīla's body continued the ascent to the Himalaya and thereby transmitted the Pacification of Suffering teachings and the Indian form of Chöd which contributed to the Mahamudra Chöd of Machig Labdrön. The mindstream of Kamalaśīla was unable to return to his own body and so was forced to enter the vacant body of Padampa Sangye.
Third Karmapa: systematizer of Chöd Chöd was a marginal and peripheral practice, and the Chödpas who engaged in it were from outside traditional Tibetan Buddhist and Indian monastic institutions, with a contraindication against all but the most advanced practitioners to go to the charnel grounds to practice. Texts concerning Chöd were both exclusive and rare in the early tradition school. Indeed, due to the itinerant and nomadic lifestyles of practitioners, they could carry few texts. Hence they were also known as kusulu or kusulupa, that is, studying texts rarely whilst focusing on meditation and praxis: "The nonconventional attitude of living on the fringe of society kept the Chödpas aloof from the wealthy monastic institutions and printing houses.
As a result, the original Chöd texts and commentaries, often copied by hand, never enjoyed any wide circulation, and many have been lost forever." Rangjung Dorje, 3rd Karmapa Lama, (1284–1339) was an important systematizer of Chöd teachings and significantly assisted in their promulgation within the literary and practice lineages of the Kagyu, Nyingma, and particularly Dzogchen. It is in this transition from the charnel grounds to the monastic institutions of Tibetan Buddhism that the rite of Chöd became an inner practice; the charnel ground became an internal imaginal environment. Schaeffer conveys that the Third Karmapa was a systematizer of the Chöd developed by Machig Labdrön and lists a number of his works in Tibetan on Chöd.
Amongst others, the works include redactions, outlines and commentaries. Western reports on Chöd practices Chöd was mostly practised outside the Tibetan monastery system by chödpas, who were yogis, yogiṇīs and ngagpas rather than bhikṣus and bhikṣuṇīs. Because of this, material on Chöd has been less widely available to Western readers than some other tantric Buddhist practices. The first Western reports of Chöd came from a French adventurer who lived in Tibet, Alexandra David-Néel in her travelogue Magic and Mystery in Tibet, published in 1932. Walter Evans-Wentz published the first translation of a Chöd liturgy in his 1935 book Tibetan Yoga and Secret Doctrines.
Anila Rinchen Palmo translated several essays about Chöd in the 1987 collection Cutting Through Ego-Clinging: Commentary on the practice of Tchod. Since then, Chöd has emerged more into the mainstream of both western scholarly and academic writings. See also Cham Dance Dampa Sangye Dhvaja Machig Labdrön Lama Tsultrim Allione Nyönpa Sky burial Tantra techniques (Vajrayana) References Primary Sources Secondary Sources Allione, Tsultrim (1984/2000). "The Biography of Machig Labdrön (1055–1145)." in Women of Wisdom. Pp. 165–220. Snow Lion Publications. Allione, Tsultrim (1998). "Feeding the Demons." in Buddhism in America. Brian D. Hotchkiss, ed. Pp. 344–363. Rutland, VT; Boston, MA; Tokyo: Charles E. Tuttle Co., Inc. Beyer, Stephen (1973).
The Cult of Tara. University of California Press. Orofino, Giacomella (2000). “The Great Wisdom Mother and the Gcod Tradition.” in Tantra in Practice. David Gordon White, ed. Pp. 396–416. Princeton, NJ: Princeton University Press. External links A Partial Genealogy of the Lifestory of Yeshé Tsogyel Category:Tibetan Buddhist concepts Category:Tibetan Buddhist practices Category:Tantric practices
Dandy–Walker malformation (DWM), also known as Dandy–Walker syndrome (DWS), is a rare congenital brain malformation in which the part joining the two hemispheres of the cerebellum (the cerebellar vermis) does not fully form, and the fourth ventricle and space behind the cerebellum (the posterior fossa) are enlarged with cerebrospinal fluid. Most of those affected develop hydrocephalus within the first year of life, which can present as increasing head size, vomiting, excessive sleepiness, irritability, downward deviation of the eyes and seizures. Other, less common symptoms are generally associated with comorbid genetic conditions and can include congenital heart defects, eye abnormalities, intellectual disability, congenital tumours, other brain defects such as agenesis of the corpus callosum, skeletal abnormalities, an occipital encephalocele or underdeveloped genitalia or kidneys.
It is sometimes discovered in adolescents or adults due to mental health problems. DWM is usually caused by a ciliopathic or chromosomal genetic condition, though the causative condition is only identified in around half of those diagnosed before birth and a third of those diagnosed after birth. The mechanism involves impaired cell migration and division affecting the long period of development of the cerebellar vermis. The mechanism by which hydrocephalus occurs in DWM is not yet fully understood. The condition is diagnosed by MRI or, less commonly, prenatal ultrasound. There are other malformations that can strongly resemble DWM, and disagreement exists around the criteria and classifications used for the malformation.
Treatment for most involves the implantation of a cerebral shunt in infancy. This is usually inserted in the posterior fossa, but a shunt in the lateral ventricles may be used instead or in conjunction. Endoscopic third ventriculostomy (ETV) is a less invasive option for patients older than 1 year. Posterior fossa shunts are most effective (80% of the time) but carry the highest risk of complications, while ETV is least effective but has the least risk of complications. The mortality rate is roughly 15%, mostly due to complications from hydrocephalus or its treatment, which can include subdural haematomas or infection.
The prognosis after successful hydrocephalus treatment is usually good but depends on any associated condition and its symptoms. Those without hydrocephalus are treated based on any associated symptoms or condition. The prevalence of DWM is estimated at between 1 in 25,000 to 1 in 50,000. DWM is the cause of around 4.3% of cases of congenital hydrocephalus and 2.5% of all cases of hydrocephalus. At least 21% of those with DWM have a sibling with the malformation, and at least 16% have a parent with the malformation. The malformation was first described by English surgeon John Bland-Sutton in 1887, though it was named by German psychiatrist in 1954 after American neurosurgeons Walter Dandy and Arthur Earl Walker, who described it in 1914 and 1942, respectively.
Signs and symptoms Hydrocephalus The most frequent and prominent symptoms of DWM are those associated with hydrocephalus in the postnatal period. Hydrocephalus occurs in an estimated 80% of patients with classic DWM. This usually presents within the first year of life (85% of the time), most often within the first 3 months. Signs of hydrocephalus in infants include increasing head size, vomiting, excessive sleepiness, irritability, downward deviation of the eyes (known as "sunsetting eyes") and seizures. In contrast to classic DWM, only around 30% of those with Dandy–Walker variant (DWV), in which the posterior fossa is not enlarged, have hydrocephalus.
Neurological Despite the hypoplastic cerebellar vermis, just over half of individuals with DWM (between 27% and 84%) do not appear to have significant intellectual disability or developmental delay. However, many of the genetic conditions associated with DWM can present with developmental delay and other brain anomalies. Agenesis of the corpus callosum has been found in between 5% and 17% of those with DWM. This does not seem to result in intellectual disability on its own, however. Other brain abnormalities known to be sometimes associated with DWM include grey matter heterotopia, pachygyria (fewer ridges in the brain), lissencephaly (shallower ridges), polymicrogyria, holoprosencephaly and schizencephaly.