(CNN) -- One of the first photos it sent home showed a self-portrait of its shadow. The dark gray specter of machinery against a lighter grainy backdrop showed up minutes after the news of its arrival, as if to say "I'm here!" With its cameras as our eyes, it opened our minds to un-roved territory. If you're a NASA engineer, you might even call it "she." Curiosity, NASA's most sophisticated and complex Mars rover, touched down on the Red Planet on the morning of August 6, 2012 (August 5 if you're in Pacific Daylight Time). The $2.5 billion mission set out to explore Gale Crater, which was thought to have once hosted flowing water, and find out if that environment was once habitable.
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Curiosity landed on Mars on August 6, 2012 (August 5 in the western U.S.)
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The rover will make a 5-mile journey to the planet's Mount Sharp
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Scientist says landing the rover itself was a major accomplishment
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Rover found evidence that life could have existed on Mars
Mars
Red Planet
Mars
Mars
Now, Curiosity is on its way to Mount Sharp, a three-mile-high structure made of layers that, scientists believe, recorded @placeholder' geological history.
Curiosity
Using instruments on board @placeholder, scientists determined that the Martian atmosphere hasn't changed much in the last 4 billion years, and during that whole time it has been thin, as well as inhospitable to life as we know it.
Mount Sharp
The rover's second year will be mostly about the five-mile drive to @placeholder, Vasavada said.