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.
Temporal Coverage
2024-04-18T09:05:00Z / 2024-04-18T18:58:00Z
Version
3.0
Mission Description
CHEOPS (Benz et al., https://doi.org/10.1007/s10686-020-09679-4) is a European Space Agency (ESA) mission in partnership with Switzerland with important contributions to the payload and the ground segment from Austria, Belgium, France, Germany, Hungary, Italy, Portugal, Spain, Sweden and the United Kingdom.
The satellite has a single payload comprising an ultra-high precision photometer covering the 330 - 1100 nm wavelength range in a single photometric band. Observations are made as part of the Guaranteed Time Observing Programme that is formulated by the CHEOPS Science Team, and the Guest Observers Programme through which the Community at large can apply for CHEOPS time.
