The Alpha Magnetic Spectrometer is loaded into the vehicle that would take it to the space shuttle launchpad on March 15. The $2 billion cosmic ray detector will be carried to the International Space Station on Endeavour's final flight. NASA hide caption

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Space shuttle Atlantis lifts off from Kennedy Space Center on May 14, 2010, in Cape Canaveral, Fla. Matt Stroshane/Getty Images hide caption

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Vostok: Earth's First Spaceship

The Vostok 3KA-2 was the last unmanned flight before Soviet cosmonaut Yuri Gagarin orbited the Earth on April 12, 1961. The rocket went into space carrying a dog named Zvezdochka and a mannequin in a spacesuit.

The Crab Nebula is filled with mysterious filaments that are tremendously complex. NASA, ESA, J. Hester, A. Loll (ASU) hide caption

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