TESS Discovery of a Transiting Super-Earth in the $\pi$ Mensae System

Chelsea X. Huang; Jennifer Burt; Andrew Vanderburg; Maximilian N. Günther; Avi Shporer; Jason A. Dittmann; Joshua N. Winn; Rob Wittenmyer; Lizhou Sha; Stephen R. Kane; George R. Ricker; Roland K. Vanderspek; David W. Latham; Sara Seager; Jon M. Jenkins; Douglas A. Caldwell; Karen A. Collins; Natalia Guerrero; Jeffrey C. Smith; Samuel N. Quinn; Stéphane Udry; Francesco Pepe; François Bouchy; Damien Ségransan; Christophe Lovis; David Ehrenreich; Maxime Marmier; Michel Mayor; Bill Wohler; Kari Haworth; Edward H. Morgan; Michael Fausnaugh; David R. Ciardi; Jessie Christiansen; David Charbonneau; Diana Dragomir; Drake Deming; Ana Glidden; Alan M. Levine; P. R. McCullough; Liang Yu; Norio Narita; Tam Nguyen; Tim Morton; Joshua Pepper; András Pál; Joseph E. Rodriguez; the TESS team

doi:10.3847/2041-8213/aaef91

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arXiv · 1809.05967

TESS Discovery of a Transiting Super-Earth in the $\pi$ Mensae System

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Abstract

We report the detection of a transiting planet around $\pi$ Mensae (HD 39091), using data from the Transiting Exoplanet Survey Satellite (TESS). The solar-type host star is unusually bright (V=5.7) and was already known to host a Jovian planet on a highly eccentric, 5.7-year orbit. The newly discovered planet has a size of $2.04\pm 0.05$ $R_\oplus$ and an orbital period of 6.27 days. Radial-velocity data from the HARPS and AAT/UCLES archives also displays a 6.27-day periodicity, confirming the existence of the planet and leading to a mass determination of $4.82\pm 0.85$ $M_\oplus$. The star's proximity and brightness will facilitate further investigations, such as atmospheric spectroscopy, asteroseismology, the Rossiter--McLaughlin effect, astrometry, and direct imaging.

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Chelsea X. Huang, Jennifer Burt, Andrew Vanderburg, Maximilian N. Günther, Avi Shporer, Jason A. Dittmann, Joshua N. Winn, Rob Wittenmyer, Lizhou Sha, Stephen R. Kane, George R. Ricker, Roland K. Vanderspek, David W. Latham, Sara Seager, Jon M. Jenkins, Douglas A. Caldwell, Karen A. Collins, Natalia Guerrero, Jeffrey C. Smith, Samuel N. Quinn, Stéphane Udry, Francesco Pepe, François Bouchy, Damien Ségransan, Christophe Lovis, David Ehrenreich, Maxime Marmier, Michel Mayor, Bill Wohler, Kari Haworth, Edward H. Morgan, Michael Fausnaugh, David R. Ciardi, Jessie Christiansen, David Charbonneau, Diana Dragomir, Drake Deming, Ana Glidden, Alan M. Levine, P. R. McCullough, Liang Yu, Norio Narita, Tam Nguyen, Tim Morton, Joshua Pepper, András Pál, Joseph E. Rodriguez, the TESS team. 2018-09-16. TESS Discovery of a Transiting Super-Earth in the $\pi$ Mensae System. https://doi.org/10.3847/2041-8213/aaef91

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