From Science Daily:

"We'll have to be really lucky to decipher an Earth-like planet's atmosphere during a transit event so that we can tell it is Earth-like," said Kaltenegger. "We will need to add up many transits to do so - hundreds of them, even for stars as close as 20 light-years away."

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"Where the telescope ends, the microscope begins. Which of the two has the greater view?" - Hugo

"Men occasionally stumble over the truth, but most pick themselves up and hurry off as if nothing had happened." - Churchill

Good article with an explaination of how hard it is, but I saw nothing in the article about how hard they used to think it might be.

So; is it really harder than they thought, or as hard as they thought, or just plain hard with no preconcieved notion?

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Numbers are not case sensitive. (me)