[astro-ph.EP] The surface of Ceres exposed to the space environment will be gradually altered, but the evolution of its spectral properties remains poorly understood. Here we analyze visible and infrared spectra acquired by the Dawn mission to investigate spectral variations across different surface units.
We identify local shifts of a few nm toward shorter wavelengths in the 2.7 μm band center, predominantly associated with freshly exposed slumping and impact materials. Our analysis suggests that compositional variations in Ceres’ regolith are unlikely the explanation for the band center shift, and therefore it may represent a spectral evolution within 106 years. Combining previous studies about the spectral reddening on Ceres, we propose a two-stage spectral evolution on Ceres.
The blue-shifted regions are interpreted as the youngest materials. Within 106 years after exposure, these materials become spectrally bluer, the 2.7 μm band weakens, and its center shifts toward longer wavelengths. Then the evolution is characterized by spectral reddening and strengthening of the 2.7 μm band without the band center shift.
Based on the previous laboratory work and observations on other C-complex asteroids, we suggest that the observed spectral variations may be attributed to the chemical and/or physical changes of the regolith, possibly associated with space weathering.
Qing Zhang, Jian-Yang Li, Yazhou Yang, Minge Liu, Yang Liu
Comments: Accepted by PSJ
Subjects: Earth and Planetary Astrophysics (astro-ph.EP)
Cite as: arXiv:2609.15158 [astro-ph.EP] (or arXiv:2609.15158v1 [astro-ph.EP] for this version)
https://doi.org/10.48550/arXiv.2609.15158
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Submission history
From: Qing Zhang
[v1] Mon, 14 Sep 2026 07:36:24 UTC (20,729 KB)
https://arxiv.org/abs/2609.15158
Astrobiology, Astrogeology,
