• Babak Tafreshi (TWAN)
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    Naked-eye Comet PanSTARRS streaks across the northern hemisphere skies on March 12. The comet appears over the western horizon after sunset, joined by the thin, flattened crescent of a day-old Moon. In silhouette against the colorful twilight glow, is the subtly lit dome of the William Herschel Telescope on the Canary Island of La Palma. 

  • NASA
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    With their scheduled stay onboard the International Space Station headed toward its final days, three members of the Expedition 34 crew pose for photographs in their Sokol suits in the U.S. Laboratory. From left are NASA astronaut Kevin Ford, commander, with Roscosmos Flight Engineers Oleg Novitskiy and Evgeny Tarelkin. The three crew members will undock their Soyuz spacecraft from the station at 8:30 p.m. EDT, March 14.

  • Cmdr_Hadfield/Twitter
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    This photo of the Sahara Desert was tweeted by Astronaut Chris Hadfield from the International Space Station on March 14. He wrote, "The dry folded skin of the Sahara desert, looking like the crust of a pie. Perfect for Pi Day! pic.twitter.com/Lhl4hyOp6s"

  • AP Photo/David Goldman
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    Grounds crew workers take a break from repairing the field to watch a fireworks display following a spring training exhibition baseball game between the Baltimore Orioles and the Minnesota Twins, Wednesday, March 13, in Fort Myers, Fla. 

  • AstroMarshburn/Twitter
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    This photo of California's Mono Lake was tweeted by Astronaut Thomas H. Marshburn from the International Space Station on March 14. He wrote, "California’s Mono lake, with no exit to the ocean pic.twitter.com/9xdp5HNF93"

  • AP Photo/Victor R. Caivano
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    Paola La Rocca celebrates after hearing that Buenos Aires' Archbishop Jorge Bergoglio was chosen as Pope at the Metropolitan Cathedral in Buenos Aires, Argentina, Wednesday, March 13. Bergoglio is the first pope ever from the Americas and the first from outside Europe in more than a millennium. 

  • AstroMarshburn/Twitter
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    This photo of Owen's Lake in the Sierra Nevadas was tweeted by astronaut Thomas Marshburn from the International Space Station on March 14. He wrote, "Owen’s Lake against 14,000 feet of Sierra Nevada Range pic.twitter.com/NHJLcuMZyN"

  • AstroMarshburn/Twitter
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    This photo of clouds off the coast of Alaska was tweeted by astronaut Thomas Marshburn from the International Space Station on March 14. He wrote, "Winter cloud layers off the coast of Alaska pic.twitter.com/oBSXUlQnI4"

  • AstroMarshburn/Twitter
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    This photo of Canadarm2, a piece of the equipment of the International Space Station, was tweeted by Astronaut Thomas H. Marshburn from the ISS on March 14. He wrote, "The Canadarm2 watches over us with CA’s Central Valley below pic.twitter.com/2FJoYmaMOt"

  • AP Photo/Matt Slocum
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    Next: Today's 10 Must-See Photos: 3-13-2013

    Miami Heat's LeBron James goes up for a dunk during an NBA basketball game against the Philadelphia 76ers, Wednesday, March 13, in Philadelphia.