[en] Giant exoplanets on wide orbits have been directly imaged around young stars. If the thermal background in the mid-infrared can be mitigated, then exoplanets with lower masses can also be imaged. Here we present a ground-based mid-infrared observing approach that enables imaging low-mass temperate exoplanets around nearby stars, and in particular within the closest stellar system, α Centauri. Based on 75-80% of the best quality images from 100 h of cumulative observations, we demonstrate sensitivity to warm sub-Neptune-sized planets throughout much of the habitable zone of α Centauri A. This is an order of magnitude more sensitive than state-of-the-art exoplanet imaging mass detection limits. We also discuss a possible exoplanet or exozodiacal disk detection around α Centauri A. However, an instrumental artifact of unknown origin cannot be ruled out. These results demonstrate the feasibility of imaging rocky habitable-zone exoplanets with current and upcoming telescopes.
Research Center/Unit :
STAR - Space sciences, Technologies and Astrophysics Research - ULiège
Disciplines :
Space science, astronomy & astrophysics
Author, co-author :
Wagner, K.; Dept. of Astronomy and Steward Observatory, University of Arizona, Tucson, AZ, USA ; NASA Nexus for Exoplanet System Science, Earths in Other Solar Systems Team, Tucson, AZ, USA
Boehle, A.; Institute for Particle Physics and Astrophysics, ETH Zurich, Zürich, Switzerland
Pathak, P.; European Southern Observatory, Garching bei München, Germany
Kasper, M.; European Southern Observatory, Garching bei München, Germany
Arsenault, R.; European Southern Observatory, Garching bei München, Germany
Jakob, G.; European Southern Observatory, Garching bei München, Germany
Käufl, U.; European Southern Observatory, Garching bei München, Germany
Leveratto, S.; European Southern Observatory, Garching bei München, Germany
Maire, Anne-Lise ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > PSILab
Pantin, E.; AIM, CEA, CNRS, Université Paris-Saclay, Université Paris Diderot, Sorbonne Paris Cité, Gif-sur-Yvette, France
Siebenmorgen, R.; European Southern Observatory, Garching bei München, Germany
Zins, G.; European Southern Observatory, Garching bei München, Germany
Absil, Olivier ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > PSILab
Apai, D.; Dept. of Astronomy and Steward Observatory, University of Arizona, Tucson, AZ, USA ; NASA Nexus for Exoplanet System Science, Earths in Other Solar Systems Team, Tucson, AZ, USA ; Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ, USA
Carlotti, A.; Univ. Grenoble Alpes, CNRS, IPAG, Grenoble, France
Choquet, É.; Aix Marseille Univ, CNRS, CNES, LAM, Marseille, France
Delacroix, Christian ; Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > PSILab
Dohlen, K.; Aix Marseille Univ, CNRS, CNES, LAM, Marseille, France
Duhoux, P.; European Southern Observatory, Garching bei München, Germany
Forsberg, P.; Department of Materials Science and Engineering, Ångström Laboratory, Uppsala University, Uppsala, Sweden
Fuenteseca, E.; European Southern Observatory, Garching bei München, Germany
Guyon, O.; Dept. of Astronomy and Steward Observatory, University of Arizona, Tucson, AZ, USA ; Subaru Telescope, National Astronomical Observatory of Japan, National Institutes of Natural Sciences (NINS), Hilo, HI, USA ; The Breakthrough Initiatives, NASA Research Park, Moffett Field, CA, USA ; James C. Wyant College of Optical Sciences, University of Arizona, Tucson, AZ, USA
Huby, E.; LESIA, Observatoire de Paris, Meudon, France
Ruane, G.; California Institute of Technology, Pasadena, CA, USA ; Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA, USA
Riquelme, M.; European Southern Observatory, Garching bei München, Germany
Soenke, C.; European Southern Observatory, Garching bei München, Germany
Sterzik, M.; European Southern Observatory, Garching bei München, Germany
Vigan, A.; Aix Marseille Univ, CNRS, CNES, LAM, Marseille, France
de Zeeuw, T.; European Southern Observatory, Garching bei München, Germany ; Sterrewacht Leiden, Leiden University, Leiden, The Netherlands ; Max Planck Institute for Extraterrestrial Physics, Garching, Germany)
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