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Earth's seven sisters

Seven small planets whose surfaces could harbour liquid water have been spotted around a nearby dwarf star. If such a configuration is common in planetary systems, our Galaxy could be teeming with Earth-like planets. See Letter p.456

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Figure 1: The TRAPPIST-1 planetary system.


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Correspondence to Ignas A. G. Snellen.

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See Futures p.512

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Snellen, I. Earth's seven sisters. Nature 542, 421–422 (2017).

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