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hmm

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are we alone

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that's a question likely asked by anyone

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who's ever stared in awe at the bright

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night sky

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until recently astronomers knew only of

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the planets in our solar system

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then in 1995 came the discovery of the

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first planets orbiting stars other than

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our sun

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could they like earth harbor life we now

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know of over 300 exoplanets planets

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around other stars but the ones that

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have been found to date fall into

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categories that are not very similar to

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the solar system with its sophisticated

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array of high resolution cameras the

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kepler spacecraft is designed to stare

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at one region of our milky way galaxy

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and capture images of any transits it

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sees a transit happens when a planet is

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passing in front of the face of its star

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it's basically the same idea as when you

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see a solar eclipse when that happens

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that's the moon passing in from the sun

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and having a dramatic decrease on the

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brightness that we see of the sun how

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much starlight is blocked by a planet's

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transit and how often that happens can

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tell astronomers the planet's size and

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orbit and whether it's in the habitable

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zone not too close nor too far away from

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its star what we want to determine is

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how rare or common is a system like the

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earth with a planet like earth in a zone

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where you could have liquid water and

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potentially life kepler will look

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continuously at well over one hundred

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thousand stars for at least three and a

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half years the data it produces should

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be a significant step in learning

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whether we've got company in our galaxy

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and tell astronomers where best to focus

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the search for neighbors it's like when

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galileo first turned his telescope to

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the heavens and everything changed the

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way we thought of ourselves and the

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universe changed and the same thing

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happened when the apollo astronauts took

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that picture of the earth when they were

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around the moon you know everyone on

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earth could see the earth differently

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from that moment on i think we'll have

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the same kind of revolution in the way

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we think of

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our solar system and our existence when

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we know how special or how common we

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really are for more on the kepler