Doppler spectroscopy as a path to the detection of Earth-like planets

Abstract

Doppler spectroscopy was the first technique used to reveal the existence of extrasolar planetary systems hosted by solar-type stars. Radial-velocity surveys led to the detection of a rich population of super-Earths and Neptune-type planets. The numerous detected systems revealed a remarkable diversity. Combining Doppler measurements with photometric observations of planets transiting their host stars further provides access to the planet bulk density, a first step towards comparative exoplanetology. The development of new high-precision spectrographs and space-based facilities will ultimately lead us to characterize rocky planets in the habitable zone of our close stellar neighbours.

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Figure 1: Exoplanet discoveries as a function of time.
Figure 2: Rossiter–McLaughlin effect for probing the spin-orbit alignment of exoplanets.
Figure 3: Mass–density diagram for Neptunes and super-Earths.
Figure 4: Metallicity distribution of planet-hosting stars.

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Acknowledgements

We thank A. Triaud for his help in preparing Fig. 2. N.C.S. was supported by Fundação para a Ciência e a Tecnologia (FCT, Portugal) through the Investigador FCT contract reference IF/00169/2012 and POPH/FSE (EC) by FEDER funding through the program Programa Operacional de Factores de Competitividade-COMPETE. N.C.S. further acknowledges the support from the European Research Council/European Community under FP7 through Starting Grant agreement number 239953. M.M and C.L. acknowledge the support of the Swiss National Science Foundation.

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Correspondence to Michel Mayor.

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Mayor, M., Lovis, C. & Santos, N. Doppler spectroscopy as a path to the detection of Earth-like planets. Nature 513, 328–335 (2014). https://doi.org/10.1038/nature13780

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