Enceladus And Jupiter As Exoplanets: The Opposition Surge Effect
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Planets and moons in our Solar System have strongly peaked reflected light phase curves at opposition. In this work, we produce a modified reflected light phase curve model and use it to fit the Cassini phase curves of Jupiter and Enceladus.
This opposition effect is caused by shadow hiding (SH; particles or rough terrain cast shadows which are not seen at zero phase) and coherent backscattering (CB; incoming light constructively interferes with outgoing light). We find tentative evidence for CB preference in Jupiter compared to SH, and no evidence of preference in Enceladus.
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Jupiter Cassini phase curves from Li et al. (2018), with their corresponding colour filter used in this analysis. The datapoint colours are a crude guide for the different wavelengths of the filters. — astro-ph.EP
We show that the full-width half-maximum (FWHM) of Jupiter’s opposition peak is an order of magnitude larger than that of Enceladus and conclude that this could be used as a solid-surface indicator for exoplanets.
We investigate this and show that modelling the opposition peak FWHM in solid-surface exoplanets would be unfeasible with JWST or the Future Habitable Worlds Observatory due to the very large signal-to-noise required over a small phase range.
K. Jones, B. M. Morris, K. Heng
Comments: Accepted into A&A, 10 pages, 10 figures
Subjects: Earth and Planetary Astrophysics (astro-ph.EP)
Cite as: arXiv:2502.14629 [astro-ph.EP] (or arXiv:2502.14629v1 [astro-ph.EP] for this version)
https://doi.org/10.48550/arXiv.2502.14629
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Related DOI:
https://doi.org/10.1051/0004-6361/202451115
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Submission history
From: Kathryn Jones
[v1] Thu, 20 Feb 2025 15:07:29 UTC (2,019 KB)
https://arxiv.org/abs/2502.14629
Astrobiology,