A Non-Detection of Iron in the First High-Resolution Emission Study of the Lava Planet 55 Cnc e

Kaitlin C. Rasmussen; Miles H. Currie; Celeste Hagee; Christiaan van Buchem; Matej Malik; Arjun B. Savel; Matteo Brogi; Emily Rauscher; Victoria Meadows; Megan Mansfield; Eliza M. R. Kempton; Jean-Michel Desert; Joost P. Wardenier; Lorenzo Pino; Michael Line; Vivien Parmentier; Andreas Seifahrt; David Kasper; Madison Brady; Jacob L. Bean

arXiv · 2308.10378

A Non-Detection of Iron in the First High-Resolution Emission Study of the Lava Planet 55 Cnc e

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Abstract

Close-in lava planets represent an extreme example of terrestrial worlds, but their high temperatures may allow us to probe a diversity of crustal compositions. The brightest and most well-studied of these objects is 55 Cancri e, a nearby super-Earth with a remarkably short 17-hour orbit. However, despite numerous studies, debate remains about the existence and composition of its atmosphere. We present upper limits on the atmospheric pressure of 55 Cnc e derived from high-resolution time-series spectra taken with Gemini-N/MAROON-X. Our results are consistent with current crustal evaporation models for this planet which predict a thin $\sim$ 100 mbar atmosphere. We conclude that, if a mineral atmosphere is present on 55 Cnc e, the atmospheric pressure is below 100 mbar.

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Kaitlin C. Rasmussen, Miles H. Currie, Celeste Hagee, Christiaan van Buchem, Matej Malik, Arjun B. Savel, Matteo Brogi, Emily Rauscher, Victoria Meadows, Megan Mansfield, Eliza M. R. Kempton, Jean-Michel Desert, Joost P. Wardenier, Lorenzo Pino, Michael Line, Vivien Parmentier, Andreas Seifahrt, David Kasper, Madison Brady, Jacob L. Bean. 2023-08-20. A Non-Detection of Iron in the First High-Resolution Emission Study of the Lava Planet 55 Cnc e. https://arxiv.org/abs/2308.10378

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