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Target RA (J2000): 181.632462 and deg Target Dec (J2000): -31.64567 and deg Gaia GMag: 10.24 Programme ID: CH_PR240022 PI of observing programme: Jenkins Title of programme: Constraining the Prevalence of Metallic Clouds within the Neptune Desert Abstract: With the recent stunning discovery of a very high albedo for the extreme Neptune Desert planet LTT9779b a result that is likely due to the presence of high-altitude metallic clouds in the atmosphere scattering the incoming starlight we are finally beginning to understand the chemical structure and evolution of these desert worlds. However given their rarity one may wonder whether such cloud structures are normal for these types of planets and if so what are the physical processes driving this. In order to respond to this question we request observations using CHEOPS to observe two other planets that have recently been confirmed to reside in the Neptune Desert and who orbit stars bright enough to significantly detect their secondary eclipses in the optical. We shall measure the eclipses of the planets TOI-1997b and TOI-2352b allowing us to place strong constraints on their albedos and therefore model their atmospheric structures. This work will provide evidence for or against the presence of highly reflective silicate and titanium clouds in these planets and allow us to begin to build a global picture of the atmospheric constituents of some of the most extreme Neptune planets currently known. [truncated! Please see actual data for full text]目标赤经（J2000坐标系）：181.632462 度 目标赤纬（J2000坐标系）：-31.64567 度 盖亚（Gaia）G星等：10.24 项目编号：CH_PR240022 观测项目首席研究员：詹金斯 项目标题：限定海王星荒漠内金属云的普遍性 摘要：近期，极端海王星荒漠行星LTT9779b被发现拥有极高反照率（albedo），这一现象大概率源于其大气中存在散射入射星光的高空金属云，如今我们终于得以洞悉这类荒漠行星的化学结构与演化历程。然而鉴于这类行星极为稀有，我们不禁疑惑：这类云结构是否是此类行星的普遍特征？若是，那么驱动其形成的物理过程又是什么？为解答这一问题，我们申请使用系外行星表征卫星（CHEOPS）观测另外两颗新近被证实位于海王星荒漠内的行星，它们的宿主恒星亮度足够高，足以在光学波段有效探测到其次生食。我们将对行星TOI-1997b与TOI-2352b的食进行观测，以此对它们的反照率施加严格约束，进而为其大气结构建立模型。本研究将为这些行星上是否存在高反射率的硅酸盐与钛云提供佐证，并助力我们构建当前已知部分极端海王星行星的大气成分全局图景。 【文本已截断，请查阅完整数据以获取全文】