Situation Room is a photograph taken by White House photographer Pete Souza in its namesake, the White House Situation Room, at 4:06 pm on May 1, 2011. It depicts U.S. President Barack Obama and Vice President Joe Biden, along with members of the national security team, watching live drone feed of Operation Neptune Spear. A Navy SEAL team assaulted the compound of Osama bin Laden, the founder and head of the Islamist militant group al-Qaeda, in Abbottabad, Pakistan. This concluded an almost decade-long hunt for bin Laden following the September 11 attacks in 2001.

Photo: Pete Souza
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The Brown Thornbill (Acanthiza pusilla) is a passerine bird usually found in eastern and south-eastern Australia. It can grow up to 10 centimetres (3.9 in) long. These thornbills are predominantly insectivores, though they may also eat seeds, fruit, or nectar.

Photo: JJ Harrison
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The Third of May 1808 is a painting completed in 1814 by the Spanish master Francisco Goya, now in the Museo del Prado, Madrid. Along with its companion piece of the same size, The Second of May 1808 (or The Charge of the Mamelukes), it was commissioned by the provisional government of Spain at Goya's suggestion. Goya sought to commemorate Spanish resistance to Napoleon's armies during the Peninsular War.

Painting: Francisco Goya
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The lar gibbon (Hylobates lar) is a primate found in South-East Asia. This endangered gibbon species is primarily a frugivore, but may also feed on leaves, flowers, and insects.

This specimen was photographed in Kaeng Krachan National Park, Phetchaburi, Thailand.

Photograph: JJ Harrison
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The Hammer retroazimuthal projection is a modified azimuthal proposed by Ernst Hermann Heinrich Hammer in 1910. As a retroazimuthal projection, azimuths (directions) are correct from any point to the designated center point. In whole-world presentation, the back and front hemispheres overlap, making the projection a surjective function. Here, the frontside and backside hemispheres, both with a 15° graticule and center point of 45°N, 90°W, are presented side-by-side.

Map: Strebe, using Geocart
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"St Simeon Stylites" is a poem written by Alfred Tennyson, 1st Baron Tennyson, in 1833 and published in his 1842 collection of poetry. The poem describes the actions of Simeon Stylites, the first pillar saint (a mediaeval Christian movement in which hermits, in the hopes of becoming closer to God, would perch atop tall columns for years, as a form of asceticism), who counts his various physical acts and hopes that he has earned his place in heaven. It captures Tennyson's feelings following the death of a close friend, Arthur Hallam, and contains feelings of self-loathing and regret. The work has ironic overtones that give it the appearance of a satirical work.

This illustration, from a 1901 edition, illustrates the following lines:

Illustration: W.E.F. Britten; restoration: Adam Cuerden
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A panoramic view of the northwest façade of Château de Chambord. Built between 1519 and 1547 by King Francis I as a hunting lodge, it was heavily extended afterwards. The château is an example of Renaissance architecture, which blends traditional French medieval forms with classical Renaissance structures. This château is the largest of the Loire Valley, measuring 156 metres (512 ft) long and topping 56 metres (184 ft) in height. Chambord has been a UNESCO World Heritage Site since 1981.

Photograph: Benh Lieu Song
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The Battle of Spotsylvania Court House was the second major battle in Ulysses S. Grant's 1864 Overland Campaign of the American Civil War. Following the Battle of the Wilderness, Grant's forces disengaged from Robert E. Lee's Confederate army and moved to the southeast. Elements of Lee's army beat the Union army to the critical crossroads of Spotsylvania Court House and began entrenching. Fighting occurred on and off from May 8 through May 21; ultimately the battle was tactically inconclusive, but with a total of almost 32,000 casualties, it was the costliest battle of the campaign.

This chromolithograph was published by L. Prang & Co. in 1887, based on the work by Thure de Thulstrup.

Illustration: Thure de Thulstrup; restoration: Adam Cuerden
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The nave of the parish church of Urtijëi, Italy; the church, dedicated to the Epiphany and to Saint Ulrich, was constructed in the 1790s and features painted domes and sculptures.

Photograph: Wolfgang Moroder
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The Horsehead Nebula is a dark nebula in the constellation Orion. It is located just to the south of the star Alnitak, which is farthest east on Orion's Belt, and is part of the much larger Orion Molecular Cloud Complex. The nebula is approximately 1500 light-years from Earth and was first recorded in 1888 by Scottish astronomer Williamina Fleming.

Photographer: Ken Crawford
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The Visible Pinball Machine, a machine for playing pinball created by the Pacific Pinball Museum with transparent surfaces to show the normally concealed mechanisms. In pinball, players manipulate one or more steel balls on a playing field to score as many points as possible; a game ends after all the balls fall into the drain located at the bottom of the slanted playing field.

Photograph: Kevin Tiell/Pacific Pinball Museum
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The Green Heron (Butorides virescens) is a heron species of North and Central America; this specimen was photographed at Corcovado National Park, Costa Rica. Adults have a body length of about 44 cm (17 in) and have been known to use tools to attract fish which they then eat.

Photograph: Basar
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Clynotis is a genus of jumping spider contained within the subfamily Marpissinae. They are found across Australia and New Zealand, with some species occupying the Auckland Islands and one found exclusively on Snares Island. This specimen, a female Clynotis severus, was found in Austins Ferry, Tasmania.

Photograph: JJ Harrison
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A chart showing the inheritance of an autosomal recessive gene, including the distinction between offspring that carry the gene but are or are not affected by it.

Diagram: Cburnett
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"The Sleeping Beauty" is a poem written by Alfred, Lord Tennyson, and published in 1830; it was later expanded and published in 1842 as "The Day-Dream". Based on the fairy tale Sleeping Beauty, the poem (as with many of Tennyson's adaptations of existing literary works) focuses on a single aspect of the story, the appearance of the eponymous character as she sleeps.

This illustration by W. E. F. Britten was published in 1901 to accompany a reprinting of "The Sleeping Beauty". It accompanies the poem's final lines: "She sleeps, nor dreams, but ever dwells / A perfect form in perfect rest."

Illustration: W. E. F. Britten; restoration: Adam Cuerden
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The Mercedes-Benz SLS AMG Roadster is a convertible version of the SLS AMG Coupé. It was unveiled at the 2011 Frankfurt International Motor Show, where this photograph was taken.

Photograph: Stephen Krause
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A self-portrait by the Mars rover Curiosity on October 31, 2012. The mosaic is stitched from a set of 55 images taken by the Mars Hand Lens Imager at "Rocknest," the spot in Gale crater where the mission's first scoop sampling took place. Self-portraits such as this help NASA document the state of the rover and track changes, such as dust accumulation and wheel wear.

Photograph: NASA
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A neutral density filter is a filter that reduces or modifies the intensity of all wavelengths or colors of light equally, giving no changes in hue of color rendition. The filter reduces the amount of light entering the lens, allowing the photographer to select combinations of aperture, exposure time and sensor sensitivity to avoid overexposed pictures. It would normally be attached to the lens, but is hand-held here to illustrate the effect.

Photograph: Robert Emperley
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Kumar Anish is an Indian yoga practitioner who has written extensively on the topic. He is credited with developing the GOPI Formula.

Photograph: Muhammad Mahdi Karim
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The Barrow Offshore Wind Farm, located off Walney Island in the Irish Sea, is a 30-turbine offshore wind farm of 90 MW capacity. Proposed in 2001, the wind farm was completed in 2006.

Photograph: Andy Dingley; edit: Muhammad Mahdi Karim
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Narbonne Cathedral is a former cathedral located in Narbonne, France. Dedicated to Saints Justus and Pastor, construction of the cathedral began in 1272 but was never finished. It served as the seat of the Archbishop of Narbonne until 1801, when a concordat merged the territory into the diocese of Carcassonne.

Photograph: Benh Lieu Song
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The Pirate Publisher—An International Burlesque that has the Longest Run on Record, an illustration by Joseph Ferdinand Keppler run in Puck in 1886. It satirizes the then-existing copyright situation where a publisher could profit by simply taking newly-published works from one country and publishing them in another, without needing to pay the authors. Amongst the authors depicted are Mark Twain, Alfred Tennyson, Émile Zola, and W. S. Gilbert, who famously premiered The Pirates of Penzance in New York in an attempt to gain American copyright, as his previous work H.M.S. Pinafore had proved so immensely popular that 150 U.S. productions had already appeared.

Illustration: Joseph Ferdinand Keppler; restoration: Adam Cuerden
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The short-tailed shearwater (Puffinus tenuirostris) is a shearwater which breeds in Australia and migrates northwards during the austral winter. The chicks of this species, one of the most common seabirds in Australian waters, are commercially harvested.

Photograph: JJ Harrison
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HMS Hood was a British battlecruiser, the last such ship built for the Royal Navy. Constructed beginning in 1916, Hood was the only Admiral-class battlecruiser to be completed. She was commissioned in 1920 and used generally for showing-the-flag exercises until the onset of the Second World War. After a refit, Hood was sent back into service. On 24 May 1941, early in the Battle of the Denmark Strait, she was struck by several German shells and exploded; only three of the 1,418 crew members survived.

Photograph: Allan C. Green; restoration: Adam Cuerden
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Marpesia zerynthia, also known as the Waiter Daggerwing, is a species of butterfly in the family Nymphalidae that occurs in, and somewhat north and south of, Mesoamerica. First described in 1823, this butterfly inhabits tropical deciduous and evergreen forests. Males can generally be found closer to the ground than females, which prefer the canopies.

Photograph: Paolo Costa Baldi
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Nemanthus annamensis is a species of sea anemone first described in 1943 from the Gulf of Tonkin and now known to inhabit central Indo-Pacific waters; this specimen was found off East Timor. The species is known to attach itself by its base and wrap itself around gorgonians; N. annamensis may also live in association with the crab Lauridromia intermedia.

Photograph: Nick Hobgood
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An image of NGC 4449, highlighting its qualities as a starburst galaxy. NGC 4449, an irregular galaxy in the constellation Canes Venatici located about 12 million light years from Earth, has a rate of star formation twice that of the Milky Way's satellite galaxy, the Large Magellanic Cloud. Interactions with nearby galaxies are thought to have influenced this star formation.

Photograph: NASA, ESA, A. Aloisi (STScI/ESA), and The Hubble Heritage (STScI/AURA)-ESA/Hubble Collaboration
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"The Deserted House" is a five-stanza poem written by Alfred, Lord Tennyson, in 1830, and included in his collection Poems, Chiefly Lyrical. The poem is characterised by its reliance on short lines which alternate in rhyme and meter to prevent a felicitous feel, a technique which has drawn much positive critical commentary. In the poem, Tennyson uses the image of a dark house as a metaphor for a dead body, underlining it with the closing stanza:

This illustration by W. E. F. Britten, showing the eponymous house, accompanied the poem in a 1901 reprint.

Illustration: W. E. F. Britten; restoration: Adam Cuerden
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The Gran Sabana is a savanna in southeastern Venezuela known for its varied landscape. Pictured here is a morning view of two tepuis, Kukenán and Roraima; although Roraima tepui is actually higher than Kukenan, due to perspective it appears lower.

Photograph: Paolo Costa Baldi
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A map of Lorentz National Park in the Indonesian province of Papua. Named for the Dutch explorer Hendrikus Albertus Lorentz, this 25,056 km² (9,674 mi²) park – the largest in South-East Asia – was established in 1997 and designated a UNESCO World Heritage Site in 1999. The park is significant for its biodiversity, much of it unknown to Western science, as well as its varied ecoregions.

Map: Sémhur and Elekhh
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The Australian white ibis (Threskiornis moluccus) is a wading bird of the ibis family, Threskiornithidae. Found in much of Australia, the species has become increasingly urban since the 1970s; this specimen was photographed in Perth.

Photograph: JJ Harrison
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