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Updated: Mar 18, 2026

Surface Mapping of Earth-like Exoplanets using Single Point Light Curves
Published on: May 10, 2020
RETRACTED: Direct imaging discovery of a Jovian exoplanet within a triple-star system
Kevin Wagner1, Dániel Apai2, Markus Kasper3
1Department of Astronomy and Steward Observatory, The University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721, USA. kwagner@as.arizona.edu.
Abstract:
Direct imaging allows for the detection and characterization of exoplanets via their thermal emission. We report the discovery via imaging of a young Jovian planet in a triple-star system and characterize its atmospheric properties through near-infrared spectroscopy. The semimajor axis of the planet is closer relative to that of its hierarchical triple-star system than for any known exoplanet within a stellar binary or triple, making HD 131399 dynamically unlike any other known system. The location of HD 131399Ab on a wide orbit in a triple system demonstrates that massive planets may be found on long and possibly unstable orbits in multistar systems. HD 131399Ab is one of the lowest mass (4 ± 1 Jupiter masses) and coldest (850 ± 50 kelvin) exoplanets to have been directly imaged.
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