Phil Plait Answers When we may see a new Pale Blue Dot

One of the biggest questions in astronomical research right now is quite simple to ask but extremely difficult to answer: In the depths of space, is there an Earth-like planet somewhere orbiting a Sun-like star?

The answer is rather surprising: almost certainly yes. We haven’t found a precise twin of Earth yet, but we’ve come mighty close. In fact, it’s likely that there are millions, perhaps billions, of planets like ours in the Milky Way alone. But right now, at this moment, we only know of one for sure: ours.

So when will we actually see that blue-green dot in our telescopes?

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