I have a question, sparked by http://http://www.cnn.com/2009/TECH/12/16/super.earth.discovery/index.html" [Broken] article, so I figured this would be the best place to put this.(adsbygoogle = window.adsbygoogle || []).push({});

That is said to be 40 light years away... So if we're seeing a planet 2.7 times the size of earth with liquid water on it, and it's 40 light years away, how do you calculate how far into the past we are seeing this planet?

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# How do I calculate light years to years?

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