Gliese 12 b: A Temperate Earth-sized Planet at 12 pc Ideal for Atmospheric Transmission Spectroscopy

Copyright and License

© 2024. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.

Acknowledgement

We thank the reviewer, whose careful reading of the manuscript and excellent suggestions have improved the quality of this Letter. We thank Andrew W. Stephens and Sandy Leggett for data reduction support for the Gemini/NIRI data. We acknowledge that the TRES team posted the results of their spectroscopic observations of Gliese 12 spanning 5 yr to ExoFOP-TESS soon after TOI-6251.01 was released, showing no large RV variations (rms = 21 m s⁻¹).

Funding for the TESS mission is provided by NASA's Science Mission Directorate. We acknowledge the use of public TESS data from pipelines at the TESS Science Office and at the TESS Science Processing Operations Center (SPOC). Resources supporting this work were provided by the NASA High-End Computing (HEC) Program through the NASA Advanced Supercomputing (NAS) Division at Ames Research Center for the production of the SPOC data products. This Letter includes data collected by the TESS mission that are publicly available from the Mikulski Archive for Space Telescopes (MAST). All the TESS data used in this Letter can be found in MAST: doi:10.17909/psfb-yg51.

The Gemini data that we used in this work are publicly available from the Gemini Observatory Archive (GOA; https://archive.gemini.edu) under the program GN-2009B-Q-10 (PI: Sergio Dieterich), whose abstract is shown at https://archive.gemini.edu/programinfo/GN-2009B-Q-10. This work is based on observations obtained with XMM-Newton, an ESA science mission with instruments and contributions directly funded by ESA Member States and NASA. This work has made use of data from the European Space Agency (ESA) mission Gaia (Gaia Collaboration et al. 2016; https://www.cosmos.esa.int/gaia), processed by the Gaia Data Processing and Analysis Consortium (DPAC; https://www.cosmos.esa.int/web/gaia/dpac/consortium). Funding for the DPAC has been provided by national institutions, in particular the institutions participating in the Gaia Multilateral Agreement. This work used the data from the Second Palomar Observatory Sky Survey (POSS-II), which was made by the California Institute of Technology with funds from the National Science Foundation, the National Geographic Society, the Sloan Foundation, the Samuel Oschin Foundation, and the Eastman Kodak Corporation. This Letter makes use of data from the MEarth Project, which is a collaboration between Harvard University and the Smithsonian Astrophysical Observatory. The MEarth Project acknowledges funding from the David and Lucile Packard Fellowship for Science and Engineering; the National Science Foundation under grants AST-0807690, AST-1109468, AST-1616624 and AST-1004488 (Alan T. Waterman Award); the National Aeronautics and Space Administration under grant No. 80NSSC18K0476 issued through the XRP Program; and the John Templeton Foundation. This work is based on HARPS data obtained from the ESO Science Archive Facility: the HARPS data are based on observations made with ESO Telescopes at the La Silla Paranal Observatory under programme ID 072.C-0488. This research has made use of the SIMBAD and VizieR services, both operated at Centre de Données astronomiques de Strasbourg (CDS; https://cds.u-strasbg.fr/) in France, and NASA's Astrophysics Data System Bibliographic Services. This research made use of Lightkurve, a Python package for Kepler and TESS data analysis (Lightkurve Collaboration et al. 2018). We used TESSCut (Brasseur et al. 2019) in the analysis that was based on TRICERATOPS (Giacalone & Dressing 2020). This publication makes use of data products from the Two Micron All Sky Survey (Skrutskie et al. 2003), which is a joint project of the University of Massachusetts and the Infrared Processing and Analysis Center/California Institute of Technology, funded by the National Aeronautics and Space Administration and the National Science Foundation. This research has made use of the NASA Exoplanet Archive (DOI:10.26133/NEA12), which is operated by the California Institute of Technology, under contract with the National Aeronautics and Space Administration under the Exoplanet Exploration Program. IRAF, which we used in reducing IRD raw data, is distributed by the National Optical Astronomy Observatories, which is operated by the Association of Universities for Research in Astronomy, Inc. (AURA) under cooperative agreement with the National Science Foundation. This research has made use of the Exoplanet Follow-up Observation Program (ExoFOP; DOI:10.26134/ExoFOP5) website, which is operated by the California Institute of Technology, under contract with the National Aeronautics and Space Administration under the Exoplanet Exploration Program. Part of the data analysis was carried out on the Multi-wavelength Data Analysis System operated by the Astronomy Data Center (ADC), National Astronomical Observatory of Japan. Part of this work was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under contract with NASA.

We are honored and grateful for the opportunity of observing the Universe from Maunakea, which has cultural, historical, and natural significance in Hawaii. We appreciate the critical support from all the current and recent Subaru and Keck Observatory staffs. Their support was essential in achieving this discovery, especially amidst the many difficulties associated with the COVID-19 pandemic.

This research is based on data collected at the Subaru Telescope, which is operated by the National Astronomical Observatory of Japan. This Letter is based on observations made with the MuSCAT2 instrument, developed by ABC, at Telescopio Carlos Sánchez, operated on the island of Tenerife by the IAC in the Spanish Observatorio del Teide. This Letter is based on observations made with the MuSCAT3 instrument, developed by the Astrobiology Center and under financial support by JSPS KAKENHI (JP18H05439) and JST PRESTO (JPMJPR1775), at Faulkes Telescope North on Maui, Hawaii, operated by the Las Cumbres Observatory. CARMENES is an instrument at the Centro Astronómico Hispano en Andalucía (CAHA) at Calar Alto (Almería, Spain), operated jointly by the Junta de Andalucía and the Instituto de Astrofísica de Andalucía (CSIC). Some of the data presented herein were obtained at the W. M. Keck Observatory, which is operated as a scientific partnership among the California Institute of Technology, the University of California, and the National Aeronautics and Space Administration. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation.

M.T. is supported by JSPS KAKENHI grant Nos. 18H05442, 15H02063, and 22000005. This work is partly supported by JSPS KAKENHI grant Nos. JP18H05439, JP21K13955, and JP21K20376 and JST CREST grant No. JPMJCR1761. M.O. is funded by the National Natural Science Foundation of China (Nos. 12250610186, 12273023). We acknowledge financial support from the Agencia Estatal de Investigación (AEI/10.13039/501100011033) of the Ministerio de Ciencia e Innovación and the ERDF "A way of making Europe" through projects PID2021-125627OB-C31, PID2021-125627OB-C32, and PID2019-109522GB-C5[1:4]; the grant PRE2020-093107 of the Pre-Doc Program for the Training of Doctors (FPI-SO) through FSE funds; and the Centre of Excellence "Severo Ochoa" and "María de Maeztu" awards to the Instituto de Astrofísica de Canarias (CEX2019-000920-S) and Institut de Ciéncies de l'Espai (CEX2020-001058-M). K.A.C. acknowledges support from the TESS mission via subaward s3449 from MIT. D.R. was supported by NASA under award No. NNA16BD14C for NASA Academic Mission Services. R.L. acknowledges funding from the University of La Laguna through the Margarita Salas Fellowship from the Spanish Ministry of Universities ref. UNI/551/2021-May 26 and under the EU Next Generation funds. M.S. acknowledges the support of the Italian National Institute of Astrophysics (INAF) through the project "The HOT-ATMOS Project: characterizing the atmospheres of hot giant planets as a key to understand the exoplanet diversity" (1.05.01.85.04). G.M. acknowledges funding from the Ariel Postdoctoral Fellowship program of the Swedish National Space Agency (SNSA). J.K. gratefully acknowledges the support of the Swedish Research Council (VR: Etableringsbidrag 2017-04945). We acknowledge the support from the Deutsche Forschungsgemeinschaft (DFG) under Research Unit FOR2544 "Blue Planets around Red Stars" through project DR 281/32-1. The results reported herein benefited from collaborations and/or information exchange within NASA's Nexus for Exoplanet System Science (NExSS) research coordination network sponsored by NASA's Science Mission Directorate under agreement No. 80NSSC21K0593 for the program "Alien Earths." Part of this work was also supported by NAOJ Research Coordination Committee, NINS, NAOJ-RCC2301-0401.

Facilities

TESS - , Keck:II (NIRC2) - KECK II Telescope, Gemini-North (Altair, NIRI) - , the 1.52 m Telescopio Carlos Sánchez (MuSCAT2) - , the 2 m Faulkes Telescope North (MuSCAT3) - , the Subaru Telescope (IRD) - , the 3.5 m Calar Alto telescope (CARMENES) - , XMN-Newton - , the ESO La Silla 3.6 m telescope (HARPS) - , SuperWASP - SuperWASP extra-solar planet detection program, ASAS-SN - , MEearth - , Exoplanet Archive -

Software References

astropy (Astropy Collaboration et al. 2013, 2018, 2022), PyAstronomy (Czesla et al. 2019; https://github.com/sczesla/PyAstronomy), corner (Foreman-Mackey2016), celerite (Foreman-Mackey et al. 2017), emcee (Foreman-Mackey et al. 2013), GGChem (Woitke & Helling 2021), IRAF (Tody 1986, 1993), IRD RV-measurement pipeline (Hirano et al. 2020), lighkurve (Lightkurve Collaboration et al. 2018), LDTk (Parviainen & Aigrain 2015), matplotlib (Hunter 2007), nirlin (https://www.gemini.edu/instrumentation/niri/data-reduction), numpy (van der Walt et al. 2011), Pandexo (Batalha et al. 2017), PyTransit(Parviainen 2015), scipy (Virtanen et al. 2020), serval (Zechmeister et al. 2018), SteParSyn (Tabernero et al. 2022), TauREx3 (Al-Refaie et al. 2021), TESSCut (Brasseur et al. 2019), TRICERATOPS (Giacalone & Dressing 2020), pandas (McKinney 2010), SymPy (Meurer et al. 2017), Google Colaboratory