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Target RA (J2000): 41.684669 and deg Target Dec (J2000): -31.17964 and deg Gaia GMag: 11.27 Programme ID: CH_PR140065 Programme Manager: WILSON PI of observing programme: Benz Title of programme: Axis 1 - Solidifying Planet-Star Composition Links by Studying Why the Internal Structures of Planets Across the Galaxy Vary (YGAL) Abstract: Terrestrial planets form through the accretion of building blocks from dust grains to proto-planets. Heavier components sink and form metallic cores whilst pebbles from beyond snow lines deliver volatiles influencing atmospheres or water on Earth-like planets. Understanding the composition of planetary ingredients is vital. Planetary refractory elemental abundances mirror stellar values the Earth is a devolatised piece of the Sun. If this is universal we would expect a diversity in internal structures and atmospheres of planets orbiting metal-diverse stars. This is currently not well investigated however in recent years tantalising evidence has emerged for metallicity-driven trends in the physical characteristics of super-Earth and sub-Neptune exoplanets. These first pieces of evidence might be pointing towards chemically-diverse formation scenarios impacting the internal structures of planets however this is currently unclear as there are very few well-characterised small planets around metal-poor stars. Therefore this program will refine the radii of a handful of key planets around Galactic thick-disk metal-poor host stars to an unprecedented level in order to solve the current mysteries that we are just starting to unravel. [truncated! Please see actual data for full text]

目标赤经（J2000坐标系）：41.684669 度 目标赤纬（J2000坐标系）：-31.17964 度 盖亚G星等：11.27 项目编号：CH_PR140065 项目负责人：WILSON 观测项目首席研究员：Benz 项目标题：轴1——通过研究银河系行星内部结构差异的成因，巩固行星-恒星成分关联（YGAL） 摘要：类地行星通过吸积从尘埃颗粒到原行星的构建模块形成。较重的成分下沉形成金属核，而雪线以外的卵石则输送挥发物，影响类地行星的大气或水。了解行星组成成分的构成至关重要。行星的难熔元素丰度反映恒星的值——地球是太阳的脱挥发物部分。如果这具有普遍性，我们预计绕金属丰度多样的恒星运行的行星，其内部结构和大气会存在多样性。目前这方面研究尚不充分，但近年来出现了诱人的证据，表明超级地球和亚海王星系外行星的物理特征存在由金属丰度驱动的趋势。这些初步证据可能指向影响行星内部结构的化学多样性形成场景，但目前尚不清楚，因为金属贫乏恒星周围特征明确的小型行星非常少。因此，本项目将把银河系厚盘金属贫乏宿主恒星周围少数关键行星的半径精度提升到前所未有的水平，以解决我们刚刚开始探索的当前谜团。[截断！请参阅实际数据获取全文]