Statue of Liberty And Venus

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The Statue of Liberty (Liberty Enlightening the World; French: La Liberté éclairant le monde) is a colossal neoclassical sculpture on Liberty Island in New York Harbor, designed by Frédéric Bartholdi and dedicated on October 28, 1886. The statue, a gift to the United States from the people of FranceDell Precision M2300 Battery, is of a robed female figure representing Libertas, the Roman goddess of freedom, who bears a torch and a tabula ansata (a tablet evoking the law) upon which is inscribed the date of the American Declaration of Independence, July 4, 1776. A broken chain lies at her feet. The statue has become an icon of freedom and of the United StatesDell Latitude 2110 Battery.

Bartholdi was inspired by French law professor and politician Édouard René de Laboulaye, who commented in 1865 that any monument raised to American independence would properly be a joint project of the French and American peoples. Due to the troubled political situation in France, work on the statue did not commence until the early 1870sDell Latitude 2100 Battery. In 1875, Laboulaye proposed that the French finance the statue and the Americans provide the pedestal and the site. Bartholdi completed the head and the torch-bearing arm before the statue was fully designed, and these pieces were exhibited for publicity at international expositions. The arm was displayed at the Centennial Exposition in 1876 and in New York's Madison Square Park from 1876 to 1882Dell Vostro 1400 Battery. Fundraising proved difficult, especially for the Americans, and by 1885 work on the pedestal was threatened due to lack of funds. Publisher Joseph Pulitzer of the World started a drive for donations to complete the project that attracted more than 120,000 contributors, most of whom gave less than a dollar. The statue was constructed in France, shipped overseas in cratesDell Inspiron 1420 Battery, and assembled on the completed pedestal on what was then called Bedloe's Island. The statue's completion was marked by New York's first ticker-tape parade and a dedication ceremony presided over by President Grover Cleveland.

The statue was administered by the United States Lighthouse Board until 1901 and then by the Department of War; since 1933 it has been maintained by the National Park Service. The statue was closed for renovation for much of 1938Dell Vostro 1700 Battery. In the early 1980s, it was found to have deteriorated to such an extent that a major restoration was required. While the statue was closed from 1984 to 1986, the torch and a large part of the internal structure were replaced. After the September 11 attacks in 2001, it was closed for reasons of safety and security; the pedestal reopened in 2004 and the statue in 2009Dell Vostro 1500 Battery, with limits on the number of visitors allowed to ascend to the crown. The statue, including the pedestal and base closed beginning on October 29, 2011, for up to a year so that a secondary staircase and other safety features can be installed; Liberty Island remains open. Public access to the balcony surrounding the torch has been barred for safety reasons since 1916Dell Inspiron 1721 Battery.

Design and construction

Origin

The origin of the Statue of Liberty project is generally traced to a comment made by French law professor and politician Édouard René de Laboulaye in mid-1865. In after-dinner conversation at his home near Versailles, Laboulaye, an ardent supporter of the Union in the American Civil War, stated: "If a monument should rise in the United States, as a memorial to their independenceDell Inspiron 1720 Battery, I should think it only natural if it were built by united effort—a common work of both our nations."[6]

Bartholdi's design patent

Laboulaye's comment was not intended as a proposal, but it inspired a young sculptor, Frédéric Bartholdi, who was present at the dinner.[6] Given the repressive nature of the regime of Napoleon III, Bartholdi took no immediate action on the idea except to discuss it with LaboulayeDell Inspiron 1521 Battery. Instead, Bartholdi approached Ismail Pasha, Khedive of Egypt, with a plan to build a huge lighthouse in the form of an ancient Egyptian female fellah or peasant, robed and holding a torch aloft, at the northern entrance to the Suez Canal in Port Said. Sketches and models were made of the proposed work, though it was never erected. There was a classical precedent for the Suez proposalDell Inspiron 1520 Battery, the Colossus of Rhodes: an ancient bronze statue of the Greek god of the sun, Helios. This statue is believed to have been over 100 feet (30 m) high, and it similarly stood at a harbor entrance and carried a light to guide ships.[7]

The American project was further delayed by the Franco-Prussian War, in which Bartholdi served as a major of militia.[6] In the war, Napoleon III was captured and deposedDell XPS M2010 Battery. Bartholdi's home province of Alsace was lost to the Prussians, and a more liberal republic was installed in France.[6] As Bartholdi had been planning a trip to the United States, he and Laboulaye decided the time was right to discuss the idea with influential Americans.[8] In June 1871, Bartholdi crossed the Atlantic, with letters of introduction signed by Laboulaye. Dell Vostro A860 Battery

Arriving at New York Harbor, Bartholdi focused on Bedloe's Island as a site for the statue, struck by the fact that vessels arriving in New York had to sail past it. He was delighted to learn that the island was owned by the United States government—it had been ceded by the New York State Legislature in 1800 for harbor defenseDell Vostro A840 Battery. It was thus, as he put it in a letter to Laboulaye: "land common to all the states."[10] As well as meeting many influential New Yorkers, Bartholdi visited President Ulysses S. Grant, who assured him that it would not be difficult to obtain the site for the statue.[11] Bartholdi crossed the United States twice by rail, and met many Americans whom he felt would be sympathetic to the project.[9] But he remained concerned that popular opinion on both sides of the Atlantic was insufficiently supportive of the proposal, and he and Laboulaye decided to wait before mounting a public campaign. Dell Vostro 1088 Battery

Bartholdi's Lion of Belfort

Bartholdi had made a first model of his concept in 1870.[13] The son of a friend of Bartholdi's, American artist John La Farge, later maintained that Bartholdi made the first sketches for the statue during his U.S. visit at La Farge's Rhode Island studio. Bartholdi continued to develop the concept following his return to France. Dell Vostro 1015 BatteryHe also worked on a number of sculptures designed to bolster French patriotism after the defeat by the Prussians. One of these was the Lion of Belfort, a monumental sculpture carved in sandstone below the fortress of Belfort, which during the war had resisted a Prussian siege for over three months. The defiant lion, 73 feet (22 m) long and half that in heightDell Vostro 1014 Battery, displays an emotional quality characteristic of Romanticism, which Bartholdi would later bring to the Statue of Liberty.[14]

Design, style, and symbolism

Detail from a fresco by Constantino Brumidi in the U.S. Capitol in Washington, D.C., showing two early symbols of America: Columbia (left) and the Indian princess

Bartholdi and Laboulaye considered how best to express the idea of American liberty.[15] In early American history, two female figures were frequently used as cultural symbols of the nation. Dell Inspiron 1410 Battery One, Columbia, was seen as an embodiment of the United States in the manner that Britannia was identified with the United Kingdom and Marianne came to represent France. Columbia had supplanted the earlier figure of an Indian princess, which had come to be regarded as uncivilized and derogatory toward Americans.[16] The other significant female icon in American culture was a representation of LibertyDell Vostro 2510 Battery, derived from Libertas, the goddess of freedom widely worshipped in ancient Rome, especially among emancipated slaves. A Liberty figure adorned most American coins of the time,[15] and representations of Liberty appeared in popular and civic art, including Thomas Crawford's Statue of Freedom (1863) atop the dome of the United States Capitol Building. Dell Vostro 1520 Battery

Artists of the 18th and 19th centuries striving to evoke republican ideals commonly used representations of Liberty.[15] A figure of Liberty was also depicted on the Great Seal of France.[15] However, Bartholdi and Laboulaye avoided an image of revolutionary liberty such as that depicted in Eugène Delacroix's famed Liberty Leading the People (1830)Dell Vostro 1510 Battery. In this painting, which commemorates France's Revolution of 1830, a half-clothed Liberty leads an armed mob over the bodies of the fallen.[16] Laboulaye had no sympathy for revolution, and so Bartholdi's figure would be fully dressed in flowing robes.[16] Instead of the impression of violence in the Delacroix work, Bartholdi wished to give the statue a peaceful appearance and chose a torch, representing progress, for the figure to hold. Dell Vostro 1320 Battery

Crawford's statue was designed in the early 1850s. It was originally to be crowned with a pileus, the cap given to emancipated slaves in ancient Rome. Secretary of War Jefferson Davis, a Southerner who would later serve as president of the Confederate States of America, was concerned that the pileus would be taken as an abolitionist symbol. He ordered that it be changed to a helmet.[18] Delacroix's figure wears a pileus, Dell Vostro 1310 Battery and Bartholdi at first considered placing one on his figure as well. Instead, he used a diadem, or crown, to top its head.[19] In so doing, he avoided a reference to Marianne, who invariably wears a pileus.[20] The seven rays form a halo or aureole.[21] They evoke the sun, the seven seas, and the seven continents,[22] and represent another means, besides the torch, whereby Liberty enlightens the world. Dell Latitude E4310 Battery

Bartholdi's early models were all similar in concept: a female figure in neoclassical style representing liberty, wearing a stola and pella (gown and cloak, common in depictions of Roman goddesses) and holding a torch aloft. The face was modeled after that of Charlotte Beysser Bartholdi, the sculptor's mother. Dell Latitude E4300 Battery He designed the figure with a strong, uncomplicated silhouette, which would be set off well by its dramatic harbor placement and allow passengers on vessels entering New York Bay to experience a changing perspective on the statue as they proceeded toward Manhattan. He gave it bold classical contours and applied simplified modeling, reflecting the huge scale of the project and its solemn purpose.[17] Bartholdi wrote of his techniqueDell Inspiron Mini 12 Battery:

Thomas Crawford's Statue of Freedom

The surfaces should be broad and simple, defined by a bold and clear design, accentuated in the important places. The enlargement of the details or their multiplicity is to be feared. By exaggerating the forms, in order to render them more clearly visible, or by enriching them with details, we would destroy the proportion of the work. Finally, the model, like the design, should have a summarized character, such as one would give to a rapid sketchDell Inspiron 1210 Battery. Only it is necessary that this character should be the product of volition and study, and that the artist, concentrating his knowledge, should find the form and the line in its greatest simplicity.[24]

Bartholdi made alterations in the design as the project evolved. Bartholdi considered having Liberty hold a broken chain, but decided this would be too divisive in the days after the Civil War. The erected statue does rise over a broken chain, half-hidden by her robes and difficult to see from the ground. Dell Studio 1737 Battery Bartholdi was initially uncertain of what to place in Liberty's left hand; he settled on a tabula ansata, a keystone-shaped tablet[25] used to evoke the concept of law.[26] Though Bartholdi greatly admired the United States Constitution, he chose to inscribe "JULY IV MDCCLXXVI" on the tablet, thus associating the date of the country's Declaration of Independence with the concept of liberty. Dell Studio 1735 Battery

Consultations with the metalwork foundry Gaget, Gauthier & Co. led Bartholdi to conclude that the skin should be made of copper sheets, beaten to shape by the repoussé method.[27] An advantage of this choice was that the entire statue would be light for its volume—the copper need be only .094 inches (2.4 mm) thick. He decided on a height of 151 feet (46 m) for the statueDell Studio 1558 Battery, double that of Italy's Colosso di San Carlo Borromeo and the German statue of Arminius, both made with the same method.[28] Bartholdi interested a former teacher of his, architect Eugène Viollet-le-Duc, in the project. Viollet-le-Duc planned to construct a brick pier within the statue, to which the skin would be anchored.[29]

Announcement and early workDell Studio 1557 Battery

By 1875, France was enjoying improved political stability and a recovering postwar economy. Growing interest in the upcoming Centennial Exhibition in Philadelphia led Laboulaye to decide it was time to seek public support.[30] In September 1875, he announced the project and the formation of the Franco-American Union as its fundraising arm. With the announcement, the statue was given a name, Liberty Enlightening the World. Dell Studio 1555 Battery The French would finance the statue; Americans would be expected to pay for the pedestal.[32] The announcement provoked a generally favorable reaction in France, though many Frenchmen resented the United States for not coming to their aid during the war with Prussia.[31] French monarchists opposed the statue, if for no other reason than it was proposed by the liberal Laboulaye, who had recently been elected a senator for life. Dell Studio 1537 BatteryLaboulaye arranged events designed to appeal to the rich and powerful, including a special performance at the Paris Opera on April 25, 1876, that featured a new cantata by composer Charles Gounod. The piece was titled La Liberté éclairant le monde, the French version of the statue's announced name. Dell Studio 1536 Battery

Stereoscopic image of right arm and torch of the Statue of Liberty, 1876 Centennial Exposition

Despite its initial focus on the elites, the Union was successful in raising funds from across French society. Schoolchildren and ordinary citizens gave, as did 181 French municipalities. Laboulaye's political allies supported the call, as did descendants of the French contingent in the American Revolutionary War. Less idealisticallyDell Studio 1535 Battery, contributions came from those who hoped for American support in the French attempt to build the Panama Canal. The firm of Japy Frères, copper merchants, donated all the copper needed to build the statue, a gift valued at 64,000 francs (about $16,000 at the time or the equivalent of $323,000 today).[33][34] The copper is said to have come from a mine in Visnes, Norway,[35] though this has not been conclusively determined. Dell Studio 14zn Battery

Although plans for the statue had not been finalized, Bartholdi moved forward with fabrication of the right arm, bearing the torch, and the head. Work began at the Gaget, Gauthier & Co. workshop.[37] In May 1876, Bartholdi traveled to the United States as a member of a French delegation to the Centennial Exhibition,[38] and arranged for a huge painting of the statue to be shown in New York as part of the Centennial festivities. Dell Studio 1440 Battery The arm did not arrive in Philadelphia until August; because of its late arrival, it was not listed in the exhibition catalogue, and while some reports correctly identified the work, others called it the "Colossal Arm" or "Bartholdi Electric Light". The exhibition grounds contained a number of monumental artworks to compete for fairgoers' interest, including an outsized fountain designed by Bartholdi. Dell Inspiron 1764 Battery Nevertheless, the arm proved popular in the exhibition's waning days, and visitors would climb up to the balcony of the torch to view the fairgrounds.[41] After the exhibition closed, the arm was transported to New York, where it remained on display in Madison Square Park for several years before it was returned to France to join the rest of the statue. Dell Inspiron 17 Battery

During his second trip to the United States, Bartholdi addressed a number of groups about the project, and urged the formation of American committees of the Franco-American Union.[42] Committees to raise money to pay for the foundation and pedestal were formed in New York, Boston, and Philadelphia. Dell Inspiron 1564 Battery The New York group eventually took on most of the responsibility for American fundraising and is often referred to as the "American Committee".[44] One of its members was 19-year-old Theodore Roosevelt, the future governor of New York and president of the United States.[42] On March 3, 1877, on his final full day in office, President Grant signed a joint resolution that authorized the President to accept the statue when it was presented by France and to select a site for it. President Rutherford B. HayesDell Inspiron 15 Battery, who took office the following day, selected the Bedloe's Island site that Bartholdi had proposed.[45]

Construction in France

The statue's head on exhibit at the Paris World's Fair, 1878

On his return to Paris in 1877, Bartholdi concentrated on completing the head, which was exhibited at the 1878 Paris World's Fair. Fundraising continued, with models of the statue put on sale. Tickets to view the construction activity at the Gaget, Gauthier & Co. workshop were also offered. Dell Inspiron 1464 Battery The French government authorized a lottery; among the prizes were valuable silver plate and a terracotta model of the statue. By the end of 1879, about 250,000 francs had been raised.[46]

The head and arm had been built with assistance from Viollet-le-Duc, who fell ill in 1879. He soon died, leaving no indication of how he intended to transition from the copper skin to his proposed masonry pier. Dell Inspiron 14 BatteryThe following year, Bartholdi was able to obtain the services of the innovative designer and builder Alexandre-Gustave Eiffel.[34] Eiffel and his structural engineer, Maurice Koechlin, decided to abandon the pier and instead build an iron truss tower. Eiffel opted not to use a completely rigid structure, which would force stresses to accumulate in the skin and lead eventually to crackingDell Inspiron 1750 Battery. To enable the statue to move slightly in the winds of New York Harbor and as the metal expanded on hot summer days, he loosely connected the support structure to the skin using what was dubbed an armature—a metal framework that ends in a mesh of metal straps, known as "saddles", that are riveted to the skin, providing firm support. In a labor-intensive processDell Inspiron 1440 Battery, each saddle had to be crafted individually.[48][49] To prevent galvanic corrosion between the copper skin and the iron support structure, Eiffel insulated the skin with asbestos impregnated with shellac.[50] The change in structural material from masonry to iron allowed Bartholdi to change his plans for the statue's assembly. He had originally expected to assemble the skin on-site as the masonry pier was builtdell Studio 1747 battery; instead he decided to build the statue in France and have it disassembled and transported to the United States for reassembly in place on Bedloe's Island.[51]

Eiffel's design made the statue one of the earliest examples of curtain wall construction, in which the exterior of the structure is not load bearing, but is instead supported by an interior framework. He included two interior spiral staircases, to make it easier for visitors to reach the observation point in the crown. dell Studio 1745 battery Access to an observation platform surrounding the torch was also provided, but the narrowness of the arm allowed for only a single ladder, 40 feet (12 m) long.[53] As the pylon tower arose, Eiffel and Bartholdi coordinated their work carefully so that completed segments of skin would fit exactly on the support structure.[54]

In a symbolic act, the first rivet placed into the skin, fixing a copper plate onto the statue's big toe, was driven by United States Ambassador to France Levi P. Morton. dell Studio 1749 battery The skin was not, however, crafted in exact sequence from low to high; work proceeded on a number of segments simultaneously in a manner often confusing to visitors.[56] Some work was performed by contractors—one of the fingers was made to Bartholdi's exacting specifications by a coppersmith in the southern French town of Montauban. dell Studio 17 battery By 1882, the statue was complete up to the waist, an event Barthodi celebrated by inviting reporters to lunch on a platform built within the statue.[58] Laboulaye died in 1883. He was succeeded as chairman of the French committee by Ferdinand de Lesseps, builder of the Suez Canal. The completed statue was formally presented to Ambassador Morton at a ceremony in Paris on July 4, 1884, and de Lesseps announced that the French government had agreed to pay for its transport to New York. dell Studio XPS 1647 battery The statue remained intact in Paris pending sufficient progress on the pedestal; by January 1885, this had occurred and the statue was disassembled and crated for its ocean voyage.[60]

Fundraising, criticism, and construction in the United States

Frank Leslie's Illustrated Newspaper, June 1885, showing woodcuts of the completed statue in Paris, Bartholdi, and the statue's interior structure

The committees in the United States faced great difficulties in obtaining funds. The Panic of 1873 had led to an economic depression that persisted through much of the decade. The Liberty statue project was not the only such undertaking that had difficulty raising moneydell Studio XPS 1645 battery: construction of the obelisk later known as the Washington Monument sometimes stalled for years; it would ultimately take over three-and-a-half decades to complete.[61] There was criticism both of Bartholdi's statue and of the fact that the gift required Americans to foot the bill for the pedestal. In the years following the Civil War, most Americans preferred realistic artworks depicting heroes and events from the nation's history, rather than allegorical works like the Liberty statue. dell Studio XPS 1640 batteryThere was also a feeling that Americans should design American public works—the selection of Italian-born Constantino Brumidi to decorate the Capitol had provoked intense criticism, even though he was a naturalized U.S. citizen.[62] Harper's Weekly declared its wish that "M. Bartholdi and our French cousins had 'gone the whole figure' while they were about it, and given us statue and pedestal at once." dell Studio XPS 16 batteryThe New York Times stated that "no true patriot can countenance any such expenditures for bronze females in the present state of our finances."[64] Faced with these criticisms, the American committees took little action for several years.[64]

The foundation of Bartholdi's statue was to be laid inside Fort Wood, a disused army base on Bedloe's Island constructed between 1807 and 1811. Since 1823, it had rarely been used, though during the Civil War, it had served as a recruiting station. dell studio xps 13 battery The fortifications of the structure were in the shape of an eleven-point star. The statue's foundation and pedestal were aligned so that it would face southeast, greeting ships entering the harbor from the Atlantic Ocean.[66] In 1881, the New York committee commissioned Richard Morris Hunt to design the pedestal. Within months, Hunt submitted a detailed plan, indicating that he expected construction to take about nine months. dell studio xps 1340 battery He proposed a pedestal 114 feet (35 m) in height; faced with money problems, the committee reduced that to 89 feet (27 m).[68]

Hunt's pedestal design contains elements of classical architecture, including Doric portals, and the large mass is fragmented with architectural detail to focus attention on the statue.[68] In form, it is a truncated pyramid, 62 feet (19 m) square at the base and 39.4 feet (12.0 m) at the top. The four sides are identical in appearanceDell Vostro 1720 Battery. Above the door on each side, there are ten disks upon which Bartholdi proposed to place the coats of arms of the states (between 1876 and 1889, there were 40 U.S. states), although this was not done. Above that, a balcony was placed on each side, framed by pillars. Bartholdi placed an observation platform near the top of the pedestal, above which the statue itself rises. Dell Vostro 1710 Battery According to author Louis Auchincloss, the pedestal "craggily evokes the power of an ancient Europe over which rises the dominating figure of the Statue of Liberty".[68] The committee hired former army General Charles Pomeroy Stone to oversee the construction work.[70] Construction on the 15-foot (4.6 m) deep foundation began in 1883, and the pedestal's cornerstone was laid in 1884. dell xps m1730 batteryIn Hunt's original conception, the pedestal was to have been made of solid granite. Financial concerns again forced him to revise his plans; the final design called for poured concrete walls, up to 20 feet (6.1 m) thick, faced with granite blocks.[71][72] The concrete mass was the largest poured to that time.[72]

Fundraising for the statue had begun in 1882. The committee organized a large number of money-raising events. dell xps m1710 battery As part of one such effort, an auction of art and manuscripts, poet Emma Lazarus was asked to donate an original work. She initially declined, stating she could not write a poem about a statue. At the time, she was also involved in aiding refugees to New York who had fled anti-Semitic pogroms in eastern Europe. These refugees were forced to live in conditions that the wealthy Lazarus had never experienceddell xps m1530 battery. She saw a way to express her empathy for these refugees in terms of the statue.[74] The resulting sonnet, "The New Colossus", including the iconic lines "Give me your tired, your poor/Your huddled masses yearning to breathe free", is uniquely identified with the Statue of Liberty and is inscribed on a plaque in the museum in the base. dell xps m1330 battery

Richard Morris Hunt's pedestal under construction in June 1885

Even with these efforts, fundraising lagged. Grover Cleveland, the governor of New York, vetoed a bill to provide $50,000 for the statue project in 1884. An attempt the next year to have Congress provide $100,000, sufficient to complete the project, failed when Democratic representatives would not agree to the appropriation. The New York committee, with only $3,000 in the bankdell xps m1210 battery, suspended work on the pedestal. With the project in jeopardy, groups from other American cities, including Boston and Philadelphia, offered to pay the full cost of erecting the statue in return for relocating it.[76] Joseph Pulitzer, publisher of the World, a New York newspaper, announced a drive to raise $100,000 (the equivalent of $2.3 million today).[33] Pulitzer pledged to print the name of every contributor, no matter how small the amount given. DELL Precision M6500 Battery The drive captured the imagination of New Yorkers, especially when Pulitzer began publishing the notes he received from contributors. "A young girl alone in the world" donated "60 cents, the result of self denial."[78] One donor gave "five cents as a poor office boy's mite toward the Pedestal Fund." A group of children sent a dollar as "the money we saved to go to the circus with." DELL Precision M6400 Battery Another dollar was given by a "lonely and very aged woman."[78] Residents of a home for alcoholics in New York's rival city of Brooklyn (the cities would not merge until 1898) donated $15; other drinkers helped out through donation boxes in bars and saloons.[80] A kindergarten class in Davenport, Iowa, mailed the World a gift of $1.35. DELL Precision M4500 Battery

As the donations flooded in, the committee resumed work on the pedestal.[81] In June, New Yorkers displayed their new-found enthusiasm for the statue, as the French vessel Isère arrived with the crates holding the disassembled statue on board. Two hundred thousand people lined the docks and hundreds of boats put to sea to welcome the Isère.[82] After five months of daily calls to donate to the statue fund, on August 11, 1885, the World announced that $102,000 had been raised from 120,000 donorsDELL Precision M4400 Battery, and that 80 percent of the total had been received in sums of less than one dollar.[83]

Even with the success of the fund drive, the pedestal was not completed until April 1886. Immediately thereafter, reassembly of the statue began. Eiffel's iron framework was anchored to steel I-beams within the concrete pedestal and assembled.[84] Once this was done, the sections of skin were carefully attached. DELL Precision M2400 BatteryDue to the width of the pedestal, it was not possible to erect scaffolding, and workers dangled from the armature by ropes while installing the skin sections. Nevertheless, no one died during the construction work.[86] Bartholdi had planned to put floodlights on the torch's balcony to illuminate it; a week before the dedication, the Army Corps of Engineers vetoed the proposalDELL Latitude E6510 Battery, fearing that ships' pilots passing the statue would be blinded. Instead, Bartholdi cut portholes in the torch (which was covered with gold leaf) and placed the lights inside them.[87] A power plant was installed on the island to light the torch and for other electrical needs.[88] After the skin was completed, renowned landscape architect Frederick Law Olmstead, designer of New York's Central Park and Brooklyn's Prospect Park, supervised a cleanup of Bedloe's Island in anticipation of the dedication. dell latitude e6500 battery

Dedication

Unveiling of the Statue of Liberty Enlightening the World (1886) by Edward Moran. Oil on canvas. The J. Clarence Davies Collection, Museum of the City of New York.

A ceremony of dedication was held on the afternoon of October 28, 1886. President Grover Cleveland, the former New York governor, presided over the event.[90] On the morning of the dedication, a parade was held in New York Citydell latitude e6400 battery; estimates of the number of people who watched it ranged from several hundred thousand to a million. President Cleveland headed the procession, then stood in the reviewing stand to see bands and marchers from across America. General Stone was the grand marshal of the parade. The route began at Madison Square, once the venue for the arm, and proceeded to Battery Park at the southern tip of Manhattan by way of Fifth Avenue and BroadwayDELL Latitude E5510 Battery, with a slight detour so the parade could pass in front of the World building on Park Row. As the parade passed the New York Stock Exchange, traders threw ticker tape from the windows, beginning the New York tradition of the ticker-tape parade.[91]

A nautical parade began at 12:45 p.m., and President Cleveland embarked on a yacht that took him across the harbor to Bedloe's Island for the dedication.[92] De Lesseps made the first speech, on behalf of the French committee, followed by the chairman of the New York committeeDELL Latitude E5410 Battery, Senator William M. Evarts. A French flag draped across the statue's face was to be lowered to unveil the statue at the close of Evarts's speech, but Bartholdi mistook a pause as the conclusion and let the flag fall prematurely. The ensuing cheers put an end to Evarts's address.[91] President Cleveland spoke next, stating that the statue's "stream of light shall pierce the darkness of ignorance and man's oppression until Liberty enlightens the world".Dell Latitude E5400 Battery Bartholdi, observed near the dais, was called upon to speak, but he refused. Orator Chauncey M. Depew concluded the speechmaking with a lengthy address.[94]

No members of the general public were permitted on the island during the ceremonies, which were reserved entirely for dignitaries. The only females granted access were Bartholdi's wife and de Lesseps's granddaughter; officials stated that they feared women might be injured in the crush of peopleDell Latitude E5500 Battery. The restriction offended area suffragists, who chartered a boat and got as close as they could to the island. The group's leaders made speeches applauding the embodiment of Liberty as a woman and advocating women's right to vote.[93] A scheduled fireworks display was postponed until November 1 because of poor weather.[95]

Shortly after the dedication, the Cleveland Gazette, an African American newspaper, suggested that the statue's torch not be lit until the United States became a free nation "in reality"dell latitude d830 battery:

"Liberty enlightening the world," indeed! The expression makes us sick. This government is a howling farce. It can not or rather does not protect its citizens within its own borders. Shove the Bartholdi statue, torch and all, into the ocean until the "liberty" of this country is such as to make it possible for an inoffensive and industrious colored man to earn a respectable living for himself and familydell latitude d820 battery, without being ku-kluxed, perhaps murdered, his daughter and wife outraged, and his property destroyed. The idea of the "liberty" of this country "enlightening the world," or even Patagonia, is ridiculous in the extreme.[96]

History since dedication

Lighthouse Board and War Department (1886–1933)

Government poster using the Statue of Liberty to promote the sale of Liberty Bonds

When the torch was illuminated on the evening of the statue's dedication, it produced only a faint gleam, barely visible from Manhattan. The World characterized it as "more like a glowworm than a beacon." dell inspiron e1705 batteryBartholdi suggested gilding the statue to increase its ability to reflect light, but this proved too expensive. The United States Lighthouse Board took over the Statue of Liberty in 1887 and pledged to install equipment to enhance the torch's effect; in spite of its efforts, the statue remained virtually invisible at night. When Bartholdi returned to the United States in 1893, he made additional suggestions, all of which proved ineffective. He did successfully lobby for improved lighting within the statuedell inspiron e1505 battery, allowing visitors to better appreciate Eiffel's design.[88] In 1901, President Theodore Roosevelt, once a member of the New York committee, ordered the statue's transfer to the War Department, as it had proved useless as a lighthouse.[97] A unit of the Army Signal Corps was stationed on Bedloe's Island until 1923, after which military police remained there while the island was under military jurisdiction. dell inspiron 9400 battery

The statue rapidly became a landmark. Many immigrants who entered through New York saw it as a welcoming sight. Oral histories of immigrants record their feelings of exhilaration on first viewing the Statue of Liberty. One immigrant who arrived from Greece recalled,

I saw the Statue of Liberty. And I said to myself, "Lady, you're such a beautiful! [sic] You opened your arms and you get all the foreigners here. Give me a chance to prove that I am worth itdell inspiron 9300 battery, to do something, to be someone in America." And always that statue was on my mind.[99]

Originally, the statue was a dull copper color, but shortly after 1900 a green patina, also called verdigris, caused by the oxidation of the copper skin, began to spread. As early as 1902 it was mentioned in the press; by 1906 it had entirely covered the statue.[100] In the belief that the patina was evidence of corrosion, Congress authorized $62,800 to paint the statue both inside and out. dell inspiron 9200 battery There was considerable public protest against the proposed exterior painting.[102] The Army Corps of Engineers studied the patina for any ill effects to the statue and concluded that it protected the skin, "softened the outlines of the Statue and made it beautiful."[103] The statue was painted only on the inside. The Corps of Engineers also installed an elevator to take visitors from the base to the top of the pedestal. dell inspiron 6400 battery

Bedloe's Island in 1927, showing the statue and army buildings. The eleven-pointed walls of Fort Wood, which still form the statue's base, are visible.

On July 30, 1916, during World War I, German saboteurs set off a disastrous explosion on the Black Tom peninsula in Jersey City, New Jersey, in what is now part of Liberty State Park, close to Bedloe's Islanddell inspiron 6000 battery. Carloads of dynamite and other explosives that were being sent to Britain and France for their war efforts were detonated, and seven people were killed. The statue sustained minor damage, mostly to the torch-bearing right arm, and was closed for ten days. The cost to repair the statue and buildings on the island was about $100,000. The narrow ascent to the torch was closed for public safety reasons, and it has remained closed ever since. dell inspiron 640M battery

That same year, Ralph Pulitzer, who had succeeded his father Joseph as publisher of the World, began a drive to raise $30,000 for an exterior lighting system to illuminate the statue at night. He claimed over 80,000 contributors but failed to reach the goal. The difference was quietly made up by a gift from a wealthy donor—a fact that was not revealed until 1936dell inspiron 630M battery. An underwater power cable brought electricity from the mainland and floodlights were placed along the walls of Fort Wood. Gutzon Borglum, who later sculpted Mount Rushmore, redesigned the torch, replacing much of the original copper with stained glass. On December 2, 1916, President Woodrow Wilson pressed the telegraph key that turned on the lights, successfully illuminating the statue. dell inspiron 600M battery

After the United States entered World War I in 1917, images of the statue were heavily used in both recruitment posters and the Liberty Bond drives that urged American citizens to support the war financially. This impressed upon the public the war's stated purpose—to secure liberty—and served as a reminder that embattled France had given the United States the statue. dell inspiron 500M battery

In 1924, President Calvin Coolidge used his authority under the Antiquities Act to declare the statue a national monument.[97] The only successful suicide in the statue's history occurred five years later, when a man climbed out of one of the windows in the crown and jumped to his death, glancing off the statue's breast and landing on the base. Dell Inspiron 1570 Battery

Early National Park Service years (1933–1982)

September 26, 1972: President Richard Nixon visits the statue to open the American Museum of Immigration. The statue's raised right foot is visible, showing that it is depicted moving forward.

In 1933, President Franklin Roosevelt ordered the statue transferred to the National Park Service (NPS). In 1937, the NPS gained jurisdiction over the rest of Bedloe's Island. Dell Inspiron 1470 Battery With the Army's departure, the NPS began to transform the island into a park.[107] The Works Progress Administration (WPA) demolished most of the old buildings, regraded and reseeded the eastern end of the island, and built granite steps for a new public entrance to the statue from its rear. The WPA also carried out restoration work within the statue, temporarily removing the rays from the statue's halo so their rusted supports could be replacedDell Inspiron 1320 Battery. Rusted cast-iron steps in the pedestal were replaced with new ones made of reinforced concrete;[108] the upper parts of the stairways within the statue were replaced, as well. Copper sheathing was installed to prevent further damage from rainwater that had been seeping into the pedestal.[109] The statue was closed to the public from May until December 1938. Dell Inspiron XPS Battery

During World War II, the statue remained open to visitors, although it was not illuminated at night due to wartime blackouts. It was lit briefly on December 31, 1943, and on D-Day, June 6, 1944, when its lights flashed "dot-dot-dot-dash," the Morse code for V, for victory. New, powerful lighting was installed in 1944–1945, and beginning on V-E DayDell Inspiron 9100 Battery, the statue was once again illuminated after sunset. The lighting was for only a few hours each evening, and it was not until 1957 that the statue was illuminated every night, all night.[110] In 1946, the interior of the statue within reach of visitors was coated with a special plastic so that graffiti could be washed away.Dell Studio 1458 Battery

In 1956, an act of Congress officially renamed Bedloe's Island as Liberty Island, a change advocated by Bartholdi generations earlier. The act also mentioned the efforts to found an American Museum of Immigration on the island, which backers took as federal approval of the project, though the government was slow to grant funds for it. Dell Studio 1457 Battery Nearby Ellis Island was made part of the Statue of Liberty National Monument by proclamation of President Lyndon Johnson in 1965.[97] In 1972, the immigration museum, in the statue's base, was finally opened in a ceremony led by President Richard Nixon. The museum's backers never provided it with an endowment to secure its future and it closed in 1991 after the opening of an immigration museum on Ellis Island. Dell Studio 1450 Battery

The statue was several times taken over briefly by demonstrators, publicizing causes such as Puerto Rican independence, opposition to abortion, and opposition to US intervention in Grenada. Demonstrations with the permission of the Park Service included a Gay Pride Parade rally and the annual Captive Baltic Nations rally. Dell Latitude D430 Battery A powerful new lighting system was installed in advance of the American Bicentennial in 1976. The statue was the focal point for Operation Sail, a regatta of tall ships from all over the world that entered New York Harbor on July 4, 1976, and sailed around Liberty Island.[113] The day concluded with a spectacular display of fireworks near the statue. Dell Latitude D420 Battery

Renovation to present (since 1982)

See also: Liberty Weekend

July 4, 1986: First Lady Nancy Reagan (in red) reopens the statue to the public.

The statue was examined in great detail by French and American engineers as part of the planning for its centennial in 1986.[115] In 1982, it was announced that the statue was in need of considerable restoration. Careful study had revealed that the right arm had been improperly attached to the main structure. It was swaying more and more when strong winds blew and there was a significant risk of structural failureDell Latitude E6520 Battery. In addition, the head had been installed 2 feet (0.61 m) off center, and one of the rays was wearing a hole in the right arm when the statue moved in the wind. The armature structure was badly corroded, and about two percent of the exterior plates needed to be replaced.[116] Although problems with the armature had been recognized as early as 1936, when cast iron replacements for some of the bars had been installedDell Latitude E6420 Battery, much of the corrosion had been hidden by layers of paint applied over the years.[117]

In May 1982, President Ronald Reagan announced the formation of the Statue of Liberty–Ellis Island Centennial Commission, led by Chrysler Corporation chair Lee Iacocca, to raise the funds needed to complete the work.[118] Through its fundraising arm, the Statue of Liberty–Ellis Island Foundation, Inc., the group raised more than $350 million in donations. Dell Latitude E6320 Battery The Statue of Liberty was one of the earliest beneficiaries of a cause marketing campaign. A 1983 promotion advertised that for each purchase made with an American Express card, the company would contribute one cent to the renovation of the statue. The campaign generated contributions of $1.7 million to the restoration project.[120]

In 1984, the statue was closed to the public for the duration of the renovationDell Latitude E6220 Battery. Workers erected scaffolding that obscured the statue from view. Liquid nitrogen was used to remove layers of paint that had been applied to the interior of the copper skin over decades, leaving two layers of coal tar, originally applied to plug leaks and prevent corrosion. Blasting with baking soda powder removed the tar without further damaging the copper.[121] The restorers' work was hampered by the asbestos-based substance that Bartholdi had used (ineffectively, as inspections showed) Dell Latitude E6120 Battery to prevent galvanic corrosion. Workers within the statue had to wear protective gear, dubbed "moon suits", with self-contained breathing circuits.[122] Larger holes in the copper skin were repaired, and new copper was added where necessary.[123] The replacement skin was taken from a copper rooftop at Bell Labs, which had a patina that closely resembled the statue'sDell Latitude E5520 Battery; in exchange, the laboratory was provided some of the old copper skin for testing.[124] The torch, found to have been leaking water since the 1916 alterations, was replaced with an exact replica of Bartholdi's unaltered torch.[125] Consideration was given to replacing the arm and shoulder; the National Park Service insisted that they be repaired instead. Dell Latitude E5420 Battery

The entire armature was replaced. The puddled iron bars used by Eiffel were gradually removed. The new bars that attach to the pylon are made of low-carbon corrosion-resistant stainless steel. The bars that now hold the staples next to the skin are made of Ferralium, an alloy that bends slightly and returns to its original shape as the statue moves.sony vgp-bps2 battery To prevent the ray and arm making contact, the ray was realigned by several degrees.[128] The lighting was again replaced—night-time illumination now comes from metal halide lamps that send beams of light to particular parts of the pedestal or statue, showing off various details.[129] Access to the pedestal, which had been through a nondescript entrance built in the 1960ssony vgp-bps3 battery, was renovated to create a wide opening framed by a set of monumental bronze doors with designs symbolic of the renovation.[130] A modern elevator was installed, allowing handicapped access to the observation area of the pedestal.[131] An emergency elevator was installed within the statue, reaching up to the level of the shoulder. sony vgp-bps4 battery

September 11, 2001: The twin towers of the World Trade Center burn with the Statue of Liberty in the foreground.

July 3–6, 1986, was designated "Liberty Weekend", marking the centennial of the statue and its reopening. President Reagan presided over the rededication, with French President François Mitterrand in attendance. July 4 saw a reprise of Operation Sail,[133] and the statue was reopened to the public on July 5. sony vgp-bps5 battery In Reagan's dedication speech, he stated, "We are the keepers of the flame of liberty; we hold it high for the world to see."[133]

Following the September 11 attacks, the statue and Liberty Island were immediately closed to the public. The island reopened at the end of 2001, while the pedestal and statue remained off-limits. The pedestal reopened in August 2004,[134] but the National Park Service announced that visitors could not safely be given access to the statue due to the difficulty of evacuation in an emergencysony vgp-bps7 battery. The Park Service adhered to that position through the remainder of the Bush administration.[135] New York Congressman Anthony D. Weiner made the statue's reopening a personal crusade.[136] On May 17, 2009, President Barack Obama's Secretary of the Interior, Ken Salazar, announced that as a "special gift" to America, the statue would be reopened to the public as of July 4, but that only a limited number of people would be permitted to ascend to the crown each day. sony vgp-bpl7 battery The statue, including the pedestal and base, closed on October 29, 2011 (the day after celebrations to mark the statue's 125th anniversary), for installation of new elevators and staircases, and to bring other facilities, such as restrooms, up to code. Although the statue is closed to the public for up to a year, Liberty Island remains open. sony vgp-bps8 battery

Access and attributes

Location and visiting

Tourists aboard a Circle Line ferry bound for Liberty Island, June 1973

The statue is situated in Upper New York Bay on Liberty Island, south of Ellis Island. Both islands were ceded by New York to the federal government in 1800.[138] As agreed in an 1834 compact between New York and New Jersey that set the state border at the bay's midpoint, the original islands remain New York territory despite their location on the New Jersey side of the state line. Land created by reclamation at Ellis is New Jersey territory. sony vgp-bps8a battery

Entrance to the Statue of Liberty National Monument is free, but there is a charge for the ferry service that all visitors must use, as private boats may not dock at the island. A concession was granted in 2007 to Statue Cruises to operate the transportation and ticketing facilities, replacing Circle Line, which had operated the service since 1953sony vgp-bps8b battery. The ferries, which depart from Liberty State Park in Jersey City and Battery Park in Lower Manhattan, also stop at Ellis Island, making a combined trip possible.[141] All ferry riders are subject to security screening, similar to airport procedures, prior to boarding.[142]

The statue, pedestal, and base are presently closed for renovation work.[1] When the structure is open, visitors intending to enter the statue's base and pedestal must obtain a complimentary museum/pedestal ticket along with their

ferry ticket. sony vgp-bpl8 battery Those wishing to climb the staircase within the statue to the crown purchase a special ticket, which may be reserved up to a year in advance. A total of 240 people per day are permitted to ascend: ten per group, three groups per hour. Climbers may bring only medication and cameras—lockers are provided for other items—and must undergo a second security screening. sony vgp-bps9 battery

Inscriptions, plaques, and dedications

Plaque honoring poet Emma Lazarus, with the text of "The New Colossus"

There are several plaques and dedicatory tablets on or near the Statue of Liberty. A plaque on the copper just under the figure in front declares that it is a colossal statue representing Liberty, designed by Bartholdi and built by the Paris firm of Gaget, Gauthier et Cie (Cie is the French abbreviation analogous to Co.) sony vgp-bps9/s battery. A presentation tablet, also bearing Bartholdi's name, declares the statue to be a gift from the people of the Republic of France that honors "the Alliance of the two Nations in achieving the Independence of the United States of America and attests their abiding friendship."[145] There is a tablet placed by the New York committee that commemorates the fundraising done to build the pedestal. The cornerstone also bears a plaque placed by the Freemasons. sony vgp-bps9a/s battery

In 1903, a bronze tablet that bears the text of "The New Colossus" and commemorates Emma Lazarus was presented by friends of the poet. Until the 1986 renovation, it was mounted inside the pedestal; today it resides in the Statue of Liberty Museum in the base. It is accompanied by a tablet given by the Emma Lazarus Commemorative Committee in 1977, celebrating the poet's life. sony vgp-bps9/b battery

A group of statues stands at the western end of the island, honoring those closely associated with the Statue of Liberty. Two Americans—Pulitzer and Lazarus—and three Frenchmen—Bartholdi, Laboulaye, and Eiffel—are depicted. They are the work of Maryland sculptor Phillip Ratner.[146]

In 1984, the Statue of Liberty was designated a UNESCO World Heritage Sitesony vgp-bps9a/b battery. The UNESCO "Statement of Significance" describes the statue as a "masterpiece of the human spirit" that "endures as a highly potent symbol—inspiring contemplation, debate and protest—of ideals such as liberty, peace, human rights, abolition of slavery, democracy and opportunity."[147]

Physical characteristics

Depictions

Main articles: Statue of Liberty in popular culture and Replicas of the Statue of Liberty

A replica of the Statue of Liberty forms part of the exterior decor at the New York-New York Hotel & Casino on the Las Vegas Stripsony vgp-bps9a battery

Hundreds of replicas of the Statue of Liberty are displayed worldwide.[148] A smaller version of the statue, one-fourth the height of the original, was given by the American community in Paris to that city. It now stands on the Île aux Cygnes, facing west toward her larger sister.[148] A replica 30 feet (9.1 m) tall stood atop the Liberty Warehouse on West 64th Street in Manhattan for many years;[148] it now resides at the Brooklyn Museum. sony vgp-bps9b batteryIn a patriotic tribute, the Boy Scouts of America, as part of their Strengthen the Arm of Liberty campaign in 1949–1952, donated about two hundred replicas of the statue, made of stamped copper and 100 inches (2,500 mm) in height, to states and municipalities across the United States.[150] Though not a true replicasony vgp-bpl9 battery, the statue known as the Goddess of Democracy temporarily erected during the Tiananmen Square protests of 1989 was similarly inspired by French democratic traditions—the sculptors took care to avoid a direct imitation of the Statue of Liberty.[151] Among other recreations of New York City structures, a replica of the statue is part of the exterior of the New York-New York Hotel & Casino in Las Vegas, Nevada. sony vgp-bps10 battery

1971 U.S. airmail stamp depicting the head of the Statue of Liberty

Reverse side of a Presidential Dollar coin

As an American icon, the Statue of Liberty has been depicted on the country's coinage and stamps. It appeared on commemorative coins issued to mark its 1986 centennial, and on New York's 2001 entry in the state quarters series.[153] An image of the statue was chosen for the American Eagle platinum bullion coins in 1997, and it was placed on the reverse, or "tails", side of the Presidential Dollar series of circulating coins. Sony VGP-BPS12 Battery Two images of the statue's torch appear on the current ten-dollar bill.[154] The statue's intended photographic depiction on a 2010 forever stamp proved instead to be of the replica at the Las Vegas casino.[155]

Depictions of the statue have been used by many regional institutions. Between 1986 and 2000, New York State issued license plates featuring the statue. Sony VGP-BPL12 Battery The Women's National Basketball Association's New York Liberty use both the statue's name and its image in their logo, in which the torch's flame doubles as a basketball.[158] The New York Rangers of the National Hockey League depicted the statue's head on their third jersey, beginning in 1997.[159] The National Collegiate Athletic Association's 1996 Men's Basketball Final Four, played at New Jersey's Meadowlands Sports Complex, featured the statue in its logo. Sony VGP-BPS13 Battery

The statue is a frequent subject in popular culture. In music, it has been evoked to indicate support for American policies, as in Toby Keith's song "Courtesy of the Red, White, & Blue (The Angry American)", and in opposition, appearing on the cover of The Dead Kennedys' album Bedtime for Democracy, which protested the Reagan administration's policies. Sony VGP-BPS13B/Q battery In film, the torch is the setting for the climax of director Alfred Hitchcock's 1942 movie Saboteur.[162] The statue makes one of its most famous cinematic appearances in the 1968 picture Planet of the Apes, in which it is seen half-buried in sand. It is destroyed in the science-fiction films Independence Day, The Day After Tomorrow, and Cloverfield.[161] In Jack Finney's time-travel novel Time and AgainSony VGP-BPS13/Q battery, the right arm of the statue, on display in the early 1880s in Madison Square Park, plays a crucial role.[164] Robert Holdstock, consulting editor of The Encyclopedia of Science Fiction, wondered in 1979,

Where would [science fiction] be without the Statue of Liberty? For decades it has towered or crumbled above the wastelands of deserted [E]arth—giants have uprooted it, aliens have found it curious ... the symbol of LibertySony VGP-BPS13A/B battery, of optimism, has become a symbol of science fiction's pessimistic view of the future."

Venus is the second planet from the Sun, orbiting it every 224.7 Earth days.[10] The planet is named after Venus, the Roman goddess of love and beauty. After the Moon, it is the brightest natural object in the night sky, reaching an apparent magnitude of −4.6, bright enough to cast shadows.[12] Because Venus is an inferior planet from Earth, it never appears to venture far from the Sun: its elongation reaches a maximum of 47.8°Sony VGP-BPS13/S battery. Venus reaches its maximum brightness shortly before sunrise or shortly after sunset, for which reason it has been known as the Morning Star or Evening Star.

Venus is classified as a terrestrial planet and it is sometimes called Earth's "sister planet" owing to their similar size, gravity, and bulk composition. Venus is covered with an opaque layer of highly reflective clouds of sulfuric acid, preventing its surface from being seen from space in visible light. Venus has the most dense atmosphere of all the terrestrial planets in the Solar SystemSony VGP-BPS13/B battery, consisting of mostly carbon dioxide. The atmospheric pressure at the planet's surface is 92 times that of the Earth. Venus has no carbon cycle to lock carbon back into rocks and surface features, nor does it seem to have any organic life to absorb it in biomass. Venus is believed to have previously possessed oceans,[13] but these evaporated as the temperature rose owing to the runaway greenhouse effect. Sony VGP-BPS13B/S battery The water has most probably photodissociated, and, because of the lack of a planetary magnetic field, the free hydrogen has been swept into interplanetary space by the solar wind.[15] Venus' surface is a dry desertscape with many slab-like rocks, periodically refreshed by volcanism.

Physical characteristics

Venus is one of the four solar terrestrial planets, meaning that, like the Earth, it is a rocky body. In size and mass, it is similar to the Earth, and is often described as Earth's "sister" or "twin".Sony VGP-BPS13A battery The diameter of Venus is 12,092 km (only 650 km less than the Earth's) and its mass is 81.5% of the Earth's. Conditions on the Venusian surface differ radically from those on Earth, owing to its dense carbon dioxide atmosphere. The mass of the atmosphere of Venus is 96.5% carbon dioxide, with most of the remaining 3.5% being nitrogen. Sony VGP-BPS13A/S battery

Geography

The Venusian surface was a subject of speculation until some of its secrets were revealed by planetary science in the 20th century. It was finally mapped in detail by Project Magellan in 1990–91. The ground shows evidence of extensive volcanism, and the sulfur in the atmosphere may indicate there have been some recent eruptions. Sony VGP-BPS13AS battery

About 80% of the Venusian surface is covered by smooth, volcanic plains, consisting of 70% plains with wrinkle ridges and 10% smooth or lobate plains.[20] Two highland "continents" make up the rest of its surface area, one lying in the planet's northern hemisphere and the other just south of the equator. The northern continent is called Ishtar Terra, after Ishtar, the Babylonian goddess of love, and is about the size of Australia. Maxwell Montes, the highest mountain on VenusSony VGP-BPS13S battery, lies on Ishtar Terra. Its peak is 11 km above the Venusian average surface elevation. The southern continent is called Aphrodite Terra, after the Greek goddess of love, and is the larger of the two highland regions at roughly the size of South America. A network of fractures and faults covers much of this area. Sony VGP-BPS13A/Q battery

The absence of evidence of lava flow accompanying any of the visible caldera remains an enigma. The planet has few impact craters, demonstrating the surface is relatively young, approximately 300–600 million years old.[22][23] In addition to the impact craters, mountains, and valleys commonly found on rocky planets, Venus has a number of unique surface featuresSony VGP-BPS13A/R battery. Among these are flat-topped volcanic features called "farra", which look somewhat like pancakes and range in size from 20–50 km across, and 100–1,000 m high; radial, star-like fracture systems called "novae"; features with both radial and concentric fractures resembling spider webs, known as "arachnoids"; and "coronae", circular rings of fractures sometimes surrounded by a depression. These features are volcanic in origin. Sony VGP-BPS13B battery

Most Venusian surface features are named after historical and mythological women.[25] Exceptions are Maxwell Montes, named after James Clerk Maxwell, and highland regions Alpha Regio, Beta Regio and Ovda Regio. The former three features were named before the current system was adopted by the International Astronomical Union, the body that oversees planetary nomenclature. Sony VGP-BPS13B/B battery

The longitudes of physical features on Venus are expressed relative to its prime meridian. The original prime meridian passed through the radar-bright spot at the center of the oval feature Eve, located south of Alpha Regio.[27] After the Venera missions were completed, the prime meridian was redefined to pass through the central peak in the crater Ariadne. Sony VGP-BPL21 battery

Surface geology

Global radar view of the surface from Magellan radar imaging between 1990-1994

Main article: Geology of Venus

Much of the Venusian surface appears to have been shaped by volcanic activity. Venus has several times as many volcanoes as Earth, and it possesses some 167 large volcanoes that are over 100 km across. The only volcanic complex of this size on Earth is the Big Island of Hawaii.[24] This is not because Venus is more volcanically active than Earth, but because its crust is olderSony VGP-BPS21 battery. Earth's oceanic crust is continually recycled by subduction at the boundaries of tectonic plates, and has an average age of about 100 million years,[30] while the Venusian surface is estimated to be 300–600 million years old.

Several lines of evidence point to ongoing volcanic activity on Venus. During the Soviet Venera program, the Venera 11 and Venera 12 probes detected a constant stream of lightning, and Venera 12 recorded a powerful clap of thunder soon after it landedSony VGP-BPS21A battery. The European Space Agency's Venus Express recorded abundant lightning in the high atmosphere.[31] While rainfall drives thunderstorms on Earth, there is no rainfall on the surface of Venus (though it does rain sulfuric acid, in the upper atmosphere, which evaporates around 25 km above the surface)Sony VGP-BPS21B battery. One possibility is ash from a volcanic eruption was generating the lightning. Another piece of evidence comes from measurements of sulfur dioxide concentrations in the atmosphere, which were found to drop by a factor of 10 between 1978 and 1986. This may imply the levels had earlier been boosted by a large volcanic eruption. Sony VGP-BPS26 Battery

Impact craters on the surface of Venus (image reconstructed from radar data)

Almost a thousand impact craters on Venus are evenly distributed across its surface. On other cratered bodies, such as the Earth and the Moon, craters show a range of states of degradation. On the Moon, degradation is caused by subsequent impacts, while on Earth, it is caused by wind and rain erosion. On Venus, about 85% of the craters are in pristine conditionSony VGP-BPS26A Battery. The number of craters, together with their well-preserved condition, indicates the planet underwent a global resurfacing event about 300–600 million years ago,[22][23] followed by a decay in volcanism.[33] Earth's crust is in continuous motion, Venus is thought to be unable to sustain such a process. Without plate tectonics to dissipate heat from its mantleSony VGP-BPS13 battery(without CD), Venus instead undergoes a cyclical process in which mantle temperatures rise until they reach a critical level that weakens the crust. Then, over a period of about 100 million years, subduction occurs on an enormous scale, completely recycling the crust.[24]

Venusian craters range from 3 km to 280 km in diameter. No craters are smaller than 3 km, because of the effects of the dense atmosphere on incoming objects. Objects with less than a certain kinetic energy are slowed down so much by the atmosphereSony VGP-BPS13B/Q battery(without CD), they do not create an impact crater.[34] Incoming projectiles less than 50 meters in diameter will fragment and burn up in the atmosphere before reaching the ground.[35]

Internal structure

Without seismic data or knowledge of its moment of inertia, little direct information is available about the internal structure and geochemistry of Venus.[36] The similarity in size and density between Venus and Earth suggests they share a similar internal structure: a core, mantle, and crust. Like that of EarthSony VGP-BPS13/Q battery(without CD), the Venusian core is at least partially liquid because the two planets have been cooling at about the same rate.[37] The slightly smaller size of Venus suggests pressures are significantly lower in its deep interior than Earth. The principal difference between the two planets is the lack of evidence for plate tectonics on Venus, possibly because its crust is too strong to subduct without water to make it less viscousSony VGP-BPS13A/B battery(without CD). This results in reduced heat loss from the planet, preventing it from cooling and providing a likely explanation for its lack of an internally generated magnetic field.[38] Instead, Venus may lose its internal heat in periodic major resurfacing events.[22]

Main article: Atmosphere of Venus

Cloud structure in the Venusian atmosphere in 1979, revealed by ultraviolet observations by Pioneer Venus OrbiterSony VGP-BPS13/S battery(without CD)

Venus has an extremely dense atmosphere, which consists mainly of carbon dioxide and a small amount of nitrogen. The atmospheric mass is 93 times that of Earth's atmosphere, while the pressure at the planet's surface is about 92 times that at Earth's surface—a pressure equivalent to that at a depth of nearly 1 kilometer under Earth's oceans. The density at the surface is 65 kg/m³ (6.5% that of water) Sony VGP-BPS13/B battery(without CD). The CO2-rich atmosphere, along with thick clouds of sulfur dioxide, generates the strongest greenhouse effect in the Solar System, creating surface temperatures of over 460 °C (860 °F).[39] This makes the Venusian surface hotter than Mercury's, which has a minimum surface temperature of −220 °C and maximum surface temperature of 420 °C,[40] even though Venus is nearly twice Mercury's distance from the Sun and thus receives only 25% of Mercury's solar irradianceSony VGP-BPS13B/S battery(without CD). The surface of Venus is often said to resemble traditional accounts of Hell.[41]

Studies have suggested that billions of years ago, the Venusian atmosphere was much more like Earth's than it is now, and that there were probably substantial quantities of liquid water on the surface, but, after a period of 600 million to several billion years,[42] a runaway greenhouse effect was caused by the evaporation of that original water, which generated a critical level of greenhouse gases in its atmosphere. Sony VGP-BPS13A battery(without CD) Although the surface conditions on the planet are no longer hospitable to any Earthlike life that may have formed prior to this event, the possibility that a habitable niche still exists in the lower and middle cloud layers of Venus can not yet be excluded.[44]

Thermal inertia and the transfer of heat by winds in the lower atmosphere mean that the temperature of the Venusian surface does not vary significantly between the night and day sides, despite the planet's extremely slow rotationSony VGP-BPS13A/S battery(without CD). Winds at the surface are slow, moving at a few kilometers per hour, but because of the high density of the atmosphere at the Venusian surface, they exert a significant amount of force against obstructions, and transport dust and small stones across the surface. This alone would make it difficult for a human to walk through, even if the heat and lack of oxygen were not a problem. Sony VGP-BPS13AS battery(without CD)

Above the dense CO2 layer are thick clouds consisting mainly of sulfur dioxide and sulfuric acid droplets.[46][47] These clouds reflect and scatter about 90% of the sunlight that falls on them back into space, and prevent visual observation of the Venusian surface. The permanent cloud cover means that although Venus is closer than Earth to the SunSony VGP-BPS13S battery(without CD), the Venusian surface is not as well lit. Strong 300 km/h winds at the cloud tops circle the planet about every four to five earth days.[48] Venusian winds move at up to 60 times the speed of the planet's rotation, while Earth's fastest winds are only 10% to 20% rotation speed.[49]

The surface of Venus is effectively isothermal; it retains a constant temperature not only between day and night but between the equator and the poles. Sony VGP-BPS13A/Q battery(without CD) The planet's minute axial tilt (less than three degrees, compared with 23 degrees for Earth), also minimizes seasonal temperature variation.[51] The only appreciable variation in temperature occurs with altitude. In 1995, the Magellan probe imaged a highly reflective substance at the tops of the highest mountain peaks that bore a strong resemblance to terrestrial snow. This substance arguably formed from a similar process to snow, albeit at a far higher temperatureSony VGP-BPS13A/R battery(without CD). Too volatile to condense on the surface, it rose in gas form to cooler higher elevations, where it then fell as precipitation. The identity of this substance is not known with certainty, but speculation has ranged from elemental tellurium to lead sulfide (galena).[52]

The clouds of Venus are capable of producing lightning much like the clouds on Earth.[53] The existence of lightning had been controversial since the first suspected bursts were detected by the Soviet Venera probesSony VGP-BPS13AB battery(without CD). In 2006–07 Venus Express clearly detected whistler mode waves, the signatures of lightning. Their intermittent appearance indicates a pattern associated with weather activity. The lightning rate is at least half of that on Earth.[53] In 2007 the Venus Express probe discovered that a huge double atmospheric vortex exists at the south pole of the planet. Sony VGP-BPS13B battery(without CD)

Another discovery made by the Venus Express probe in 2011 is that an ozone layer exists high in the atmosphere of Venus.[56]

Magnetic field and core

Size comparison of terrestrial planets (left to right): Mercury, Venus, Earth, and Mars

In 1967, Venera-4 found the Venusian magnetic field is much weaker than that of Earth. This magnetic field is induced by an interaction between the ionosphere and the solar wind, rather than by an internal dynamo in the core like the one inside the EarthSony VGP-BPS13B/B battery(without CD). Venus's small induced magnetosphere provides negligible protection to the atmosphere against cosmic radiation. This radiation may result in cloud-to-cloud lightning discharges.[59]

The lack of an intrinsic magnetic field at Venus was surprising given it is similar to Earth in size, and was expected also to contain a dynamo at its core. A dynamo requires three things: A conducting liquid, rotation, and convectionSony VGP-BPL21 battery(without CD). The core is thought to be electrically conductive and, while its rotation is often thought to be too slow, simulations show it is adequate to produce a dynamo.[60][61] This implies the dynamo is missing because of a lack of convection in the Venusian core. On Earth, convection occurs in the liquid outer layer of the core because the bottom of the liquid layer is much hotter than the topSony VGP-BPS21 battery(without CD). On Venus, a global resurfacing event may have shut down plate tectonics and led to a reduced heat flux through the crust. This caused the mantle temperature to increase, thereby reducing the heat flux out of the core. As a result, no internal geodynamo is available to drive a magnetic field. Instead, the heat energy from the core is being used to reheat the crust. Sony VGP-BPS21A battery(without CD)

One possibility is Venus has no solid inner core,[63] or its core is not currently cooling, so the entire liquid part of the core is at approximately the same temperature. Another possibility is its core has already completely solidified. The state of the core is highly dependent on the concentration of sulfur, which is unknown at present. Sony VGP-BPS21B battery(without CD)

The weak magnetosphere around Venus means the solar wind is interacting directly with the outer atmosphere of the planet. Here, ions of hydrogen and oxygen are being created by the dissociation of neutral molecules from ultraviolet radiation. The solar wind then supplies energy that gives some of these ions sufficient velocity to escape the planet's gravity fieldSony VGP-BPS14/B Battery. This erosion process results in a steady loss of low-mass hydrogen, helium, and oxygen ions, while higher-mass molecules, such as carbon dioxide, are more likely to be retained. Atmospheric erosion by the solar wind most probably led to the loss of most of the planet's water during the first billion years after it formed. The erosion has increased the ratio of higher-mass deuterium to lower-mass hydrogen in the upper atmosphere by a multiple of 150 times the ratio in the lower atmosphere. Sony VGP-BPS14B Battery

Orbit and rotation

Venus orbits the Sun at an average distance of about 108 million kilometers (about 0.7 AU) and completes an orbit every 224.65 days. Venus is the second planet from the Sun and it revolves round the Sun approximately 1.6 times (yellow trail) in Earth's 365 days (blue trail)

Venus orbits the Sun at an average distance of about 0.72 AU (108,000,000 km; 67,000,000 mi), and completes an orbit every 224.65 daysSony VGP-BPS14/S Battery. Although all planetary orbits are elliptical, Venus is the closest to circular, with an eccentricity of less than 0.01.[2] When Venus lies between the Earth and the Sun, a position known as inferior conjunction, it makes the closest approach to Earth of any planet at an average distance of 41 million km.[2] The planet reaches inferior conjunction every 584 days, on average. Sony VGP-BPL14/B BatteryOwing to the decreasing eccentricity of Earth's orbit, the minimum distances will become greater over tens of thousands of years. From the year 1 to 5383, 526 approaches less than 40 million km happen; then happen none for about 60,158 years.[65] During periods of greater eccentricity, Venus can come as close as 38.2 million km. Sony VGP-BPL14 Battery

All the planets of the Solar System orbit the Sun in a counter-clockwise direction as viewed from above the Sun's north pole. Most planets also rotate on their axis in a counter-clockwise direction, but Venus rotates clockwise (called "retrograde" rotation) once every 243 Earth days—by far the slowest rotation period of any major planet. The equator of the Venusian surface rotates at 6.5 km/hSony VGP-BPL14B Battery, while on Earth rotation speed at the equator is about 1,670 km/h.[66] A Venusian sidereal day thus lasts longer than a Venusian year (243 versus 224.7 Earth days). Because of the retrograde rotation, the length of a solar day on Venus is significantly shorter than the sidereal day. As a result of Venus's relatively long solar day, one Venusian year is about 1.92 Venusian days long. Sony VGP-BPL14/S Battery To an observer on the surface of Venus, the Sun would appear to rise in the west and set in the east and the time from one sunrise to the next would be 116.75 Earth days (making the Venusian solar day shorter than Mercury's 176 Earth days).[11]

Venus may have formed from the solar nebula with a different rotation period and obliquity, reaching to its current state because of chaotic spin changes caused by planetary perturbations and tidal effects on its dense atmosphereSony VGP-BPS14 Battery, a change that would have occurred over the course of billions of years. The rotation period of Venus may represent an equilibrium state between tidal locking to the Sun's gravitation, which tends to slow rotation, and an atmospheric tide created by solar heating of the thick Venusian atmosphere. A curious aspect of the Venusian orbit and rotation periods is the 584-day average interval between successive close approaches to the Earth is almost exactly equal to five Venusian solar days. Sony VGP-BPL15/B Battery However, the hypothesis of a spin–orbit resonance with Earth has been discounted.[70]

Venus currently has no natural satellite,[71] though the asteroid 2002 VE68 presently maintains a quasi-orbital relationship with it.[72] In the 17th century, Giovanni Cassini reported a moon orbiting Venus, which was named Neith and numerous sightings were reported over the following 200 years, but most were determined to be stars in the vicinitySony VGP-BPS15/B Battery. Alex Alemi's and David Stevenson's 2006 study of models of the early Solar System at the California Institute of Technology shows Venus likely had at least one moon created by a huge impact event billions of years ago.[73][74] About 10 million years later, according to the study, another impact reversed the planet's spin direction and caused the Venusian moon gradually to spiral inwardSony VGP-BPL15/S Battery until it collided and merged with Venus. If later impacts created moons, these also were absorbed in the same way. An alternative explanation for the lack of satellites is the effect of strong solar tides, which can destabilize large satellites orbiting the inner terrestrial planets.[71]

Observation

Venus is always brighter than the brightest stars outside our solar system, as can be seen here over the Pacific OceanSony VGP-BPS15/S Battery

Phases of Venus and evolution of its apparent diameter

Venus is always brighter than any star (apart from the Sun). The greatest luminosity, apparent magnitude −4.9,[8] occurs during crescent phase when it is near the Earth. Venus fades to about magnitude −3 when it is backlit by the Sun.[7] The planet is bright enough to be seen in a mid-day clear sky,[76] and the planet can be easy to see when the Sun is low on the horizonSony VGP-BPS15 Battery. As an inferior planet, it always lies within about 47° of the Sun.[9]

Venus "overtakes" the Earth every 584 days as it orbits the Sun.[2] As it does so, it changes from the "Evening Star", visible after sunset, to the "Morning Star", visible before sunrise. While Mercury, the other inferior planet, reaches a maximum elongation of only 28° and is often difficult to discern in twilight, Venus is hard to miss when it is at its brightest. Its greater maximum elongation means it is visible in dark skies long after sunsetSony VGP-BPS18 battery. As the brightest point-like object in the sky, Venus is a commonly misreported "unidentified flying object". U.S. President Jimmy Carter reported having seen a UFO in 1969, which later analysis suggested was probably the planet. Countless other people have mistaken Venus for something more exotic. Sony VGP-BPS22 Battery

As it moves around its orbit, Venus displays phases in a telescopic view like those of the Moon: In the phases of Venus, the planet presents a small "full" image when it is on the opposite side of the Sun. It shows a larger "quarter phase" when it is at its maximum elongations from the Sun, and is at its brightest in the night sky, and presents a much larger "thin crescent" in telescopic views as it comes around to the near side between the Earth and the Sun Sony VPCCA15FA/B Battery. Venus is at its largest and presents its "new phase" when it is between the Earth and the Sun. Its atmosphere can be seen in a telescope by the halo of light refracted around the planet.[9]

2004 transit of Venus

Main articles: Transits of Venus and Transit of Venus, 2012

The Venusian orbit is slightly inclined relative to the Earth's orbit; thus, when the planet passes between the Earth and the Sun, it usually does not cross the face of the Sun. Transits of Venus do occur when the planet's inferior conjunction coincides with its presence in the plane of the Earth's orbitSony VPCCA15FA/G Battery. Transits of Venus occur in cycles of 243 years with the current pattern of transits being pairs of transits separated by eight years, at intervals of about 105.5 years or 121.5 years—a pattern first discovered in 1639 by English astronomer Jeremiah Horrocks.[78]

The latest pair was June 8, 2004 and June 5–6, 2012. The transit could be watched live from many online outlets or observed locally with the right equipment and conditions. Sony VPCCA15FA/L Battery

The preceding pair of transits occurred in December 1874 and December 1882; the following pair will occur in December 2117 and December 2125.[80] Historically, transits of Venus were important, because they allowed astronomers to directly determine the size of the astronomical unit, and hence the size of the Solar System as shown by Horrocks in 1639. Sony VPCCA15FA/P Battery Captain Cook's exploration of the east coast of Australia came after he had sailed to Tahiti in 1768 to observe a transit of Venus.

Ashen light

A long-standing mystery of Venus observations is the so-called ashen light—an apparent weak illumination of the dark side of the planet, seen when the planet is in the crescent phase. The first claimed observation of ashen light was made as long ago as 1643Sony VPCCA15FA/W Battery, but the existence of the illumination has never been reliably confirmed. Observers have speculated it may result from electrical activity in the Venusian atmosphere, but it may be illusory, resulting from the physiological effect of observing a bright, crescent-shaped object.[84]

The "black drop effect" as recorded during the 1769 transit

Venus was known to ancient civilizations both as the "morning star" and as the "evening star", names that reflect the early understanding that these were two separate objectsSony VPCEH1AJ Battery. The Venus tablet of Ammisaduqa, dated 1581 BC, shows the Babylonians understood the two were a single object, referred to in the tablet as the "bright queen of the sky," and could support this view with detailed observations.[85] The Greeks thought of the two as separate stars, Phosphorus and Hesperus, until the time of Pythagoras in the sixth century BC. Sony VPCEH1E1E BatteryThe Romans designated the morning aspect of Venus as Lucifer, literally "Light-Bringer", and the evening aspect as Vesper.

The first recorded observation of a transit of Venus was made by Jeremiah Horrocks on December 4, 1639 (November 24 under the Julian calendar in use at that time), along with his friend, William Crabtree, at each of their respective homes. Sony VPCEH1J1E Battery

Galileo's discovery that Venus showed phases (while remaining near the Sun in our sky) proved that it orbits the Sun and not the Earth

When the Italian physicist Galileo Galilei first observed the planet in the early 17th century, he found it showed phases like the Moon, varying from crescent to gibbous to full and vice versa. When Venus is furthest from the Sun in the skySony VPCEH1J8E Battery, it shows a half-lit phase, and when it is closest to the Sun in the sky, it shows as a crescent or full phase. This could be possible only if Venus orbited the Sun, and this was among the first observations to clearly contradict the Ptolemaic geocentric model that the Solar System was concentric and centered on the Earth.Sony VPCEH1L0E Battery

The atmosphere of Venus was discovered in 1761 by Russian polymath Mikhail Lomonosov. Venus's atmosphere was observed in 1790 by German astronomer Johann Schröter. Schröter found when the planet was a thin crescent, the cusps extended through more than 180°. He correctly surmised this was due to scattering of sunlight in a dense atmosphereSony VPCEH1L8E Battery. Later, American astronomer Chester Smith Lyman observed a complete ring around the dark side of the planet when it was at inferior conjunction, providing further evidence for an atmosphere.[91] The atmosphere complicated efforts to determine a rotation period for the planet, and observers such as Italian-born astronomer Giovanni Cassini and Schröter incorrectly estimated periods of about 24 hours from the motions of markings on the planet's apparent surface. Sony VPCEH1L9E Battery

Ground-based research

Modern telescopic view of Venus from Earth's surface

Little more was discovered about Venus until the 20th century. Its almost featureless disc gave no hint what its surface might be like, and it was only with the development of spectroscopic, radar and ultraviolet observations that more of its secrets were revealed. The first UV observations were carried out in the 1920s, when Frank E. Ross found that UV photographs revealed considerable detail that was absent in visible and infrared radiationSony VPCEH1M1E Battery. He suggested this was due to a very dense, yellow lower atmosphere with high cirrus clouds above it.[93]

Spectroscopic observations in the 1900s gave the first clues about the Venusian rotation. Vesto Slipher tried to measure the Doppler shift of light from Venus, but found he could not detect any rotation. He surmised the planet must have a much longer rotation period than had previously been thought. Sony VPCEH1M9E Battery Later work in the 1950s showed the rotation was retrograde. Radar observations of Venus were first carried out in the 1960s, and provided the first measurements of the rotation period which were close to the modern value.[95]

Radar observations in the 1970s revealed details of the Venusian surface for the first time. Pulses of radio waves were beamed at the planet using the 300-m radio telescope at Arecibo ObservatorySony VPCEH1S0E Battery, and the echoes revealed two highly reflective regions, designated the Alpha and Beta regions. The observations also revealed a bright region attributed to mountains, which was called Maxwell Montes.[96] These three features are now the only ones on Venus which do not have female names.[97]

Main article: Observations and explorations of Venus

The first robotic space probe mission to Venus, and the first to any planet, began on February 12, 1961, with the launch of the Venera 1 probeSony VPCEH1S1E Battery. The first craft of the otherwise highly successful Soviet Venera program, Venera 1 was launched on a direct impact trajectory, but contact was lost seven days into the mission, when the probe was about 2 million km from Earth. It was estimated to have passed within 100,000 km of Venus in mid-May.[98]

The United States exploration of Venus also started badly with the loss of the Mariner 1 probe on launchSony VPCEH1S8E Battery. The subsequent Mariner 2 mission enjoyed greater success, and after a 109-day transfer orbit on December 14, 1962, it became the world's first successful interplanetary mission, passing 34,833 km above the surface of Venus. Its microwave and infrared radiometers revealed that while the Venusian cloud tops were cool, the surface was extremely hot—at least 425°C, finally ending any hopes that the planet might harbor ground-based lifeSony VPCEH1S9E Battery. Mariner 2 also obtained improved estimates of its mass and of the astronomical unit, but was unable to detect either a magnetic field or radiation belts.[99]

Pioneer Venus Multiprobe

The Soviet Venera 3 probe crash-landed on Venus on March 1, 1966. It was the first man-made object to enter the atmosphere and strike the surface of another planet, though its communication system failed before it was able to return any planetary data.[100] On October 18, 1967, Venera 4 successfully entered the atmosphere and deployed a number of science experimentsSony VPCEH1Z1E Battery. Venera 4 showed the surface temperature was even hotter than Mariner 2 had measured at almost 500°C, and the atmosphere was about 90 to 95% carbon dioxide. The Venusian atmosphere was considerably denser than Venera 4's designers had anticipated, and its slower than intended parachute descent meant its batteries ran down before the probe reached the surface. After returning descent data for 93 minutes, Venera 4's last pressure reading was 18 bar at an altitude of 24.96 km. Sony VPCEH2C0E Battery

One day later on October 19, 1967, Mariner 5 conducted a fly-by at a distance of less than 4000 km above the cloud tops. Mariner 5 was originally built as backup for the Mars-bound Mariner 4, but when that mission was successful, the probe was refitted for a Venus mission. A suite of instruments more sensitive than those on Mariner 2, in particular its radio occultation experiment, returned data on the compositionSony VPCEH2D0E Battery, pressure and density of the Venusian atmosphere.[101] The joint Venera 4 – Mariner 5 data were analyzed by a combined Soviet-American science team in a series of colloquia over the following year,[102] in an early example of space cooperation.[103]

Armed with the lessons and data learned from Venera 4, the Soviet Union launched the twin probes Venera 5 and Venera 6 five days apart in January 1969Sony VPCEH2E0E Battery; they encountered Venus a day apart on May 16 and 17 that year. The probes were strengthened to improve their crush depth to 25 bar and were equipped with smaller parachutes to achieve a faster descent. Since then-current atmospheric models of Venus suggested a surface pressure of between 75 and 100 bar, neither was expected to survive to the surfaceSony VPCEH2F1E Battery. After returning atmospheric data for a little over 50 minutes, they both were crushed at altitudes of approximately 20 km before going on to strike the surface on the night side of Venus.[100]

Surface and atmospheric science

Venera 7 represented an effort to return data from the planet's surface, and was constructed with a reinforced descent module capable of withstanding a pressure of 180 bar. The module was precooled before entry and equipped with a specially reefed parachute for a rapid 35-minute descentSony VPCEH2H1E Battery. While entering the atmosphere on December 15, 1970, the parachute is believed to have partially torn, and the probe struck the surface with a hard, yet not fatal, impact. Probably tilted onto its side, it returned a weak signal, supplying temperature data for 23 minutes, the first telemetry received from the surface of another planet.[100]

The Venera program continued with Venera 8 sending data from the surface for 50 minutes, after entering the atmosphere on July 22, 1972Sony VPCEH2J1E Battery. Venera 9, which entered the atmosphere of Venus on October 22, 1975, and Venera 10, which entered the atmosphere three days later on October 25, sent the first images of the Venusian landscape. The two landing sites presented very different terrains in the immediate vicinities of the landers: Venera 9 had landed on a 20-degree slope scattered with boulders around 30–40 cm across; Venera 10 showed basalt-like rock slabs interspersed with weathered material. Sony VPCEH2L9E Battery

In the meantime, the United States had sent the Mariner 10 probe on a gravitational slingshot trajectory past Venus on its way to Mercury. On February 5, 1974, Mariner 10 passed within 5790 km of Venus, returning over 4000 photographs as it did so. The images, the best then achieved, showed the planet to be almost featureless in visible light, but ultraviolet light revealed details in the clouds that had never been seen in Earth-bound observations. Sony VPCEH2M1E Battery

The American Pioneer Venus project consisted of two separate missions.[106] The Pioneer Venus Orbiter was inserted into an elliptical orbit around Venus on December 4, 1978, and remained there for over 13 years, studying the atmosphere and mapping the surface with radar. The Pioneer Venus Multiprobe released a total of four probes which entered the atmosphere on December 9, 1978, returning data on its composition, winds and heat fluxes. Sony VPCEH2M9E Battery

Venera 13 landing site

Four more Venera lander missions took place over the next four years, with Venera 11 and Venera 12 detecting Venusian electrical storms;[108] and Venera 13 and Venera 14, landing four days apart on March 1 and March 5, 1982, returning the first color photographs of the surface. All four missions deployed parachutes for braking in the upper atmosphereSony VPCEH2N1E Battery, but released them at altitudes of 50 km, the dense lower atmosphere providing enough friction to allow for unaided soft landings. Both Venera 13 and 14 analyzed soil samples with an on-board X-ray fluorescence spectrometer, and attempted to measure the compressibility of the soil with an impact probe.[108] Venera 14, though, had the misfortune to strike its own ejected camera lens cap and its probe failed to contact the soil.Sony VPCEH2P0E Battery The Venera program came to a close in October 1983, when Venera 15 and Venera 16 were placed in orbit to conduct mapping of the Venusian terrain with synthetic aperture radar.[109]

In 1985, the Soviet Union took advantage of the opportunity to combine missions to Venus and Comet Halley, which passed through the inner Solar System that year. En route to Halley, on June 11 and June 15, 1985Sony VPCEH2Q1E Battery, the two spacecraft of the Vega program each dropped a Venera-style probe (of which Vega 1's partially failed) and released a balloon-supported aerobot into the upper atmosphere. The balloons achieved an equilibrium altitude of around 53 km, where pressure and temperature are comparable to those at Earth's surface. They remained operational for around 46 hoursSony VPCEH2S9E Battery, and discovered the Venusian atmosphere was more turbulent than previously believed, and subject to high winds and powerful convection cells.

Radar mapping

Magellan radar topographical map of Venus (false color)

Early Earth-based radar provided a basic idea of the surface. The Pioneer Venus and the Veneras provided improved resolution.

The United States' Magellan probe was launched on May 4, 1989, with a mission to map the surface of Venus with radar.[26] The high-resolution images it obtained during its 4½ years of operation far surpassed all prior maps and were comparable to visible-light photographs of other planetsSony VPCEH2Z1E Battery. Magellan imaged over 98% of the Venusian surface by radar,[112] and mapped 95% of its gravity field. In 1994, at the end of its mission, Magellan was sent to its destruction into the atmosphere of Venus to quantify its density.[113] Venus was observed by the Galileo and Cassini spacecraft during fly-bys on their respective missions to the outer planets, but Magellan would be the last dedicated mission to Venus for over a decade. Sony VPCEH3B1E Battery

Current and future missions

NASA's MESSENGER mission to Mercury performed two fly-bys of Venus in October 2006 and June 2007, to slow its trajectory for an eventual orbital insertion of Mercury in March 2011. MESSENGER collected scientific data on both those fly-bys.[116]

The Venus Express probe was designed and built by the European Space Agency. Launched on November 9, 2005 by a Russian Soyuz-Fregat rocket procured through StarsemSony VPCEH3D0E Battery, it successfully assumed a polar orbit around Venus on April 11, 2006.[117] The probe is undertaking a detailed study of the Venusian atmosphere and clouds, including mapping of the planet's plasma environment and surface characteristics, particularly temperatures. One of the first results emerging from Venus Express is the discovery that a huge double atmospheric vortex exists at the south pole of the planet. Sony VPCEH3N1E Battery

Artist's impression of a Stirling cooled Venus Rover devised by NASA.[118]

The Japan Aerospace Exploration Agency (JAXA) devised a Venus orbiter, Akatsuki (formerly "Planet-C"), which was launched on May 20, 2010, but the craft failed to enter orbit in December 2010. Hopes remain that the probe can successfully hibernate and make another insertion attempt in six years. Planned investigations included surface imaging with an infrared camera and experiments designed to confirm the presence of lightningSony VPCEH3N6E Battery, as well as the determination of the existence of current surface volcanism.[119]

The European Space Agency (ESA) hopes to launch a mission to Mercury in 2014, called BepiColombo, which will perform two fly-bys of Venus before it reaches Mercury orbit in 2020.[120]

Under its New Frontiers Program, NASA has proposed a lander mission called the Venus In-Situ Explorer to land on Venus to study surface conditions and investigate the elemental and mineralogical features of the regolithSony VPCEH3T9E Battery. The probe would be equipped with a core sampler to drill into the surface and study pristine rock samples not weathered by the harsh surface conditions. A Venus atmospheric and surface probe mission, "Surface and Atmosphere Geochemical Explorer" (SAGE), was selected by NASA as a candidate mission study in the 2009 New Frontiers selection,[121] but the mission was not selected for flightSony VPCEJ1E1E Battery.

The Venera-D (Russian: Венера-Д) probe is a proposed Russian space probe to Venus, to be launched around 2016, with its goal to make remote-sensing observations around the planet Venus and deploying a lander, based on the Venera design, capable of surviving for a long duration on the planet's surface. Other proposed Venus exploration concepts include rovers, balloons, and airplanes. Sony VPCEJ1J1E Battery

Manned fly-by concept

Main article: Manned Venus Fly-by

A manned Venus fly-by mission, using Apollo program hardware, was proposed in the late 1960s.[123] The mission was planned to launch in late October or early November 1973, and would have used a Saturn V to send three men to fly past Venus in a flight lasting approximately one year. The spacecraft would have passed approximately 5,000 kilometres from the surface of Venus about four months later. Sony VPCEJ1L1E Battery

Spacecraft timeline

This is a list of attempted and successful spacecraft that have left Earth to explore Venus more closely.[124] Venus has also been imaged by the Hubble Space Telescope in Earth orbit, and distant telescopic observations is another source of information about Venus.Cultural understandingsSony VPCEJ1M1E Battery

As one of the brightest objects in the sky, Venus has been known since prehistoric times and as such has gained an entrenched position in human culture. It is described in Babylonian cuneiformic texts such as the Venus tablet of Ammisaduqa, which relates observations that possibly date from 1600 BC.[128] The Babylonians named the planet Ishtar (Sumerian Inanna), the personification of womanhood, and goddess of love. Sony VPCEJ1S1E Battery She had a dual role as a goddess of war, thereby representing a deity that presided over birth and death.[130]

The Ancient Egyptians believed Venus to be two separate bodies and knew the morning star as Tioumoutiri and the evening star as Ouaiti.[131] Likewise, believing Venus to be two bodies, the Ancient Greeks called the morning star Φωσφόρος, Phosphoros (Latinized Phosphorus), the "Bringer of Light" or Ἐωσφόρος, Eosphoros (Latinized Eosphorus), the "Bringer of Dawn"Sony VPCEJ1Z1E Battery. The evening star they called Hesperos (Latinized Hesperus) (Ἓσπερος, the "star of the evening"). By Hellenistic times, the ancient Greeks realized the two were the same planet, which they named after their goddess of love, Aphrodite (Phoenician Astarte).

[134] Hesperos would be translated into Latin as Vesper and Phosphoros as Lucifer ("Light Bearer"), a poetic term later used to refer to the fallen angel cast out of heaven. Sony VPCEJ2B1E BatteryThe Romans, who derived much of their religious pantheon from the Greek tradition, named the planet Venus after their goddess of love.[135] Pliny the Elder (Natural History, ii,37) identified the planet Venus with Isis.[136]

In Iranian mythology, especially in Persian mythology, the planet usually corresponds to the goddess Anahita. In some parts of Pahlavi literature the deities Aredvi Sura and Anahita are regarded as separate entitiesSony VPCEJ2D1E Battery, the first one as a personification of the mythical river and the latter as a goddess of fertility which is associated with the planet Venus. As the goddess Aredvi Sura Anahita—and simply called Anahita as well—both deities are unified in other descriptions, e. g. in the Greater Bundahishn, and are represented by the planet. In the Avestan text Mehr Yasht (Yasht 10) there is a possible early link to MithraSony VPCEJ2E1E Battery. The Persian name of the planet today is "Nahid" which derives from Anahita and later in history from the Pahlavi language Anahid.

Rooftop observers of the 2012 Venus transit, in Prague, Czech Republic

The planet Venus was important to the Maya civilization, who developed a religious calendar based in part upon its motions, and held the motions of Venus to determine the propitious time for events such as war. They named it Noh Ek', the Great StarSony VPCEJ2J1E Battery, and Xux Ek', the Wasp Star. The Maya were aware of the planet's synodic period, and could compute it to within a hundredth part of a day.[141]

The Maasai people named the planet Kileken, and have an oral tradition about it called The Orphan Boy.[142]

Venus is important in many Australian aboriginal cultures, such as that of the Yolngu people in Northern Australia. The Yolngu gather after sunset to await the rising of Venus, which they call Barnumbirr. As she approaches, in the early hours before dawnSony VPCEJ2L1E Battery, she draws behind her a rope of light attached to the Earth, and along this rope, with the aid of a richly decorated "Morning Star Pole", the people are able to communicate with their dead loved ones, showing that they still love and remember them. Barnumbirr is also an important creator-spirit in the Dreaming, and "sang" much of the country into life. Sony VPCEJ2S1E Battery

Venus plays a prominent role in Pawnee mythology. The Pawnee, a North American native tribe, until as late as 1838, practiced a morning star ritual in which a girl was sacrificed to the morning star.[144] In the metaphysical system of Theosophy, it is believed that on the etheric plane of Venus there is a civilization that existed hundreds of millions of years before Earth's[145] and it is also believed that the governing deity of Earth, Sanat Kumara, is from Venus. Sony VPCEJ2Z1E Battery

See also: Venus (mythology) and Venus (astrology)

In literature

Main article: Venus in fiction

The impenetrable Venusian cloud cover gave science fiction writers free rein to speculate on conditions at its surface; all the more so when early observations showed that not only was it similar in size to Earth, it possessed a substantial atmosphere. Closer to the Sun than Earth, the planet was frequently depicted as warmer, but still habitable by humans.Sony VPCEJ3T1E Battery The genre reached its peak between the 1930s and 1950s, at a time when science had revealed some aspects of Venus, but not yet the harsh reality of its surface conditions. Findings from the first missions to Venus showed the reality to be quite different, and brought this particular genre to an end.[148] As scientific knowledge of Venus advanced, so science fiction authors endeavored to keep pace, particularly by conjecturing human attempts to terraform Venus. Sony VPCEJM1E Battery

Perhaps the strangest appearance of Venus in literature is as the harbinger of destruction in Immanuel Velikovsky's Worlds in Collision (1950). In this intensely controversial book, Velikovsky argued that many seemingly unbelievable stories in the Old Testament are true recollections of times when Venus nearly collided with the Earth Sony VPCEL1E1E Battery— when it was still a comet and had not yet become the docile planet that we know today. He contended that Venus caused most of the strange events of the Exodus. He cites legends in many other cultures (such as Greek, Mexican, Chinese and Indian) indicating that the effects of the near-collision were global. The scientific community rejected his wildly unorthodox book, but it became a bestsellerSony VPCEL2S1E Battery.

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