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One of the most poetic sights of the Apollo missions: a crescent Earth seen from the Apollo 15 command module during the trip back home, 51 years ago #Today bit.ly/2aGDtCC
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This is the Bonsai tree that was planted in 1625, survived the devastation of the Hiroshima bombing 77 years ago #Today and is still growing today [read more: buff.ly/3Qn5kuP]
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Born #Today in 1908, Mary G. Ross was the first known Native American female engineer, and the first female engineer in the history of Lockheed, remembered for her work on aerospace design and design concepts for interplanetary space travel [read more: buff.ly/2OX5Gtd]
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This is the Great Daylight Fireball that grazed the Earth's atmosphere exactly 50 years ago #Today. The atmospheric pass modified its orbit, but it is probably still in an Earth-crossing trajectory and passed close again in 1997 bit.ly/2aYwgzS
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41 years ago #Today, the IBM PC was introduced: it quickly became market's standard de facto [read more: bit.ly/2bospiQ]
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45 years ago #Today, the Shuttle Enterprise made its first free flight piloted by Apollo 13's Fred Haise bit.ly/1U5nZwz
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Born 135 years ago #Today, Erwin Schrödinger was physicist and father of the quantum theory. He formulated the wave equation and revealed the identity of his development of the formalism and matrix mechanics bit.ly/1SgOYi8 [gif: buff.ly/3lXGPZq]
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90 years ago #Today, Amelia Earhart became the first woman to fly non-stop across the United States ubm.io/2wBNM9G
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413 years ago #Today, Galileo Galilei revealed his telescope to a group of Venetian lawmakers included the Doge bit.ly/2vokIOB
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Born #Today in 1918, Katherine Johnson was the mathematician whose calculations of orbital mechanics as a NASA employee were critical to the success of the first and subsequent U.S. crewed spaceflights buff.ly/2Fr9KwO
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139 years ago #Today, the Krakatoa volcano erupted with the most violent blast known in the recorded history bit.ly/1PVUt6e
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Born #Today in 1919, Maurice Hilleman developed over 40 vaccines, among which measles, mumps, hepatitis, chickenpox, meningitis, pneumonia: an unparalleled record of productivity that saved more lives than any other scientist of the 20th century buff.ly/2o9ChmY
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#Today in 1974, on a flight to the Farnborough Air Show outside London, Maj. James Sullivan and Maj. Noel Widdifield flew the Lockheed SR-71 Blackbird from New York to London in 1 hour, 54 minutes, 56.4 seconds, still a world record for that route buff.ly/3DB6Ns8
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Announced 22 years ago #Today, the Nokia 3310 is one of the most successful phones, with 126 million units sold worldwide. It's still widely acclaimed today and has gained a cult status due to its remarkable durability [read more: buff.ly/3cD1pMe]
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Frank Drake, the eminent radio astronomer known for his pioneering efforts in the search for extraterrestrial intelligence, among which the Arecibo message and the Drake equation, died #Today at his home in Aptos, California. He was 92 buff.ly/3e82xb4
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20 years ago #Today, a strange object designated J002E3 was discovered. It was in a temporary orbit around the Earth. It turned out to be an Apollo 12 rocket stage launched in 1969 that had returned [read more: buff.ly/2NIA6yu]
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55 years ago #Today, Sweden switched from left-hand to right-hand traffic. This is a picture of Stockholm on that day [read more: bit.ly/2vDCfGU]
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75 years ago #Today, a moth was found in the Panel F of the Harvard Mark II calculator: the first computer bug [read more: buff.ly/3tre2xW]
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21 years ago #Today, astronaut Frank Culbertson was on the International Space Station during Expedition 3 and witnessed the September 11th attacks from space [read more: buff.ly/3hleJE4] #September11
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5 years ago #Today, @CassiniSaturn reached the end of its pluriennial mission in space. A mission meant to last 3 years in orbit around Saturn, and instead the spacecraft spent 13 years, 76 days there, closing with a Grand Finale [360° coverage: buff.ly/2xe4XwK]