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Today's featured article A transit of Venus across the Sun takes place when the planet Venus passes directly between the Sun and Earth, becoming visible against the solar disk. During a transit, Venus can be seen from Earth as a small black disk moving slowly across the face of the Sun. A transit is similar to a solar eclipse by the Moon, but while the diameter of Venus is more than three times that of the Moon it is much further from Earth and so appears smaller and generally takes longer (up to eight hours) to travel across the solar disk. Transits of Venus are among the rarest of predictable astronomical phenomena—they occur in a pattern that repeats every 243 years, with pairs of transits eight years apart separated by long gaps of 121.5 years and 105.5 years. The next transit of Venus occurs on 5 and 6 June 2012, and will be the last Venus transit this century. Historically, Venus transits were of great scientific importance as they were used to gain the first realistic estimates of the size of the solar system. A transit of Venus can be safely observed by taking the same precautions used when observing the partial phases of a solar eclipse. (more...) Recently featured: Japanese aircraft carrier Kaga – Sweet Track – Elizabeth II Did you know... From Wikipedia's newest content: ... that Leicestershire (pictured) are the only team that have been English Twenty20 cricket champions more than once? ... that Blur guitarist Graham Coxon recorded 21 tracks for his 10-track album A+E? ... that cutthroat grass is primarily found in only two counties in central Florida? ... that the Marinens Flyvebaatfabrikk M.F.6 floatplane trainer was the Royal Norwegian Navy Air Service's last pusher aircraft? ... that Henk Ten Berge of De Telegraaf described When the Light Comes as "one of the strangest films ever produced by a Dutchman"? ... that in 386 BC Duke Tai of Tian Qi was formally recognized as ruler of the state of Qi, ending over six centuries of rule by the House of Jiang? ... that the 1907 Sydney bathing costume protests were a response by men wearing women's clothing to proposed regulations on beach dress?

In the news A thousand vessels parade down the River Thames in London as part of the Diamond Jubilee of Queen Elizabeth II. A passenger plane crashes into a building in Lagos, Nigeria, killing all 153 people on board. Former Egyptian President Hosni Mubarak (pictured) is sentenced to life imprisonment for his role in the killing of demonstrators during the 2011 Egyptian revolution. The International Union of Pure and Applied Chemistry approves the names flerovium and livermorium for two recently discovered synthetic elements. Viswanathan Anand defeats Boris Gelfand to win a fourth consecutive World Chess Championship. On this day... June 5: World Environment Day; Father's Day and Constitution Day in Denmark 1832 – The June Rebellion, an anti-monarchist uprising of students, broke out in Paris. 1849 – A new constitution was introduced in Denmark, establishing a constitutional monarchy and the Rigsdag, a bicameral parliament consisting of the Landsting and the Folketing. 1941 – Second Sino-Japanese War: During one sortie in a five-year bombing campaign on Chongqing, 4,000 people died of asphyxiation when the tunnel they were hiding in became blocked. 1981 – The Centers for Disease Control recorded a cluster of Pneumocystis pneumonia cases among homosexual men in Los Angeles, the first reported cases of AIDS. 2001 – Tropical Storm Allison (pictured) made landfall in southeast Texas, causing $5.5 billion in damage to make it the costliest tropical storm in US history. More anniversaries: June 4 – June 5 – June 6 It is now June 5, 2012 (UTC) – Refresh this page

Today's featured picture A ripe pitaya and the cross-section of another. "Pitaya" is the name of the fruit of several species of cactus, most importantly of the genus Hylocereus, which are also known as dragon fruits. Hylocerus are native to Central and South America and were introduced to Asia, likely by Europeans. Photo: S. Masters Recently featured: Phallus indusiatus – Springbok – Martha Washington

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