258. Silicate clouds and a circumplanetary disk in the YSES-1 exoplanet system.
作者: K K W Hoch.;M Rowland.;S Petrus.;E Nasedkin.;C Ingebretsen.;J Kammerer.;M Perrin.;V D'Orazi.;W O Balmer.;T Barman.;M Bonnefoy.;G Chauvin.;C Chen.;R J De Rosa.;J Girard.;E Gonzales.;M Kenworthy.;Q M Konopacky.;B Macintosh.;S E Moran.;C V Morley.;P Palma-Bifani.;L Pueyo.;B Ren.;E Rickman.;J-B Ruffio.;C A Theissen.;K Ward-Duong.;Y Zhang.
来源: Nature. 2025年
Young exoplanets provide a critical link between understanding planet formation and atmospheric evolution1. Direct imaging spectroscopy allows us to infer the properties of young, wide orbit, giant planets with high signal-to-noise. This allows us to compare this young population to exoplanets characterized with transmission spectroscopy, which has indirectly revealed the presence of clouds2-4, photochemistry5, and a diversity of atmospheric compositions6-7. Direct detections have also been made for brown dwarfs8-9, but direct studies of young giant planets in the mid-infrared were not possible prior to JWST10. With two exoplanets around a solar type star, the YSES-1 system is an ideal laboratory for studying this early phase of exoplanet evolution. We report the first direct observations of silicate clouds in the atmosphere of the exoplanet YSES-1 c through its 9-11 µm absorption feature, and the first circumplanetary disk silicate emission around its sibling planet, YSES-1 b. The clouds of YSES-1 c are composed of either amorphous iron-enriched pyroxene or a combination of amorphous MgSiO3 and Mg2SiO4, with particle sizes of ≤0.1 μm at 1 millibar of pressure. We attribute the emission from the disk around YSES-1 b to be from submicron olivine dust grains, which may have formed through collisions of planet-forming bodies in the disk.
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