Zhaoyang Hu

Abstract The duration and dynamic evolution of surface water on Mars are key to understanding its past habitability. Utopia Planitia, Mars’ largest northern basin, preserves mineralogical signatures of ancient aqueous activity that remains chronologically unconstrained. Here, we present the quantitative reconstruction of the Hesperian Ocean’s lifecycle using spectral analysis of manganese (Mn) (hydr)oxides as paleohydrological markers.

Abstract Atmospheric chemistry in Venus remains elusive, especially the photochemical role of sulfur species and the unexplained presence of ammonia (NH3). Here we show, through combined experiments and quantum chemical calculations, that elemental sulfur (S0) can photoreduce nitrate (NO3−) to NH3 under Venus-like acidic and UV-irradiated conditions.

Submitted: 21 October 2025 You are already at the latest version Subscription Notify me about updates to this article or when a peer-reviewed version is published. This version is not peer-reviewed. Haiyang Li  †,Yuyang Zhang  †,Zhaoyang Hu  *,Jin Liu  * Haiyang Li  †,Yuyang Zhang  †,Zhaoyang Hu  *,Jin Liu  * † Haiyang Li and Yuyang Zhang contributed equally to this work.