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A Mars-sized exoplanet

Analysis of Kepler data has yielded the smallest known mass for an exoplanet orbiting a normal star. Its mass and size are similar to those of Mars, setting a benchmark for the properties of exoplanets smaller than Earth. See Letter p.321

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Figure 1: The planetary system Kepler-138.


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Correspondence to Gregory Laughlin.

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Laughlin, G. A Mars-sized exoplanet. Nature 522, 290–291 (2015).

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