Obliquity Influences Pluto and Triton's Distinct Landscapes and Climates

Recent research has highlighted the contrasting climatic and geological features of Pluto and Triton, two celestial bodies believed to share a common origin in the Kuiper Belt. The study, titled "Twin Worlds, Divergent Fates: How Obliquity has differently shaped Pluto's and Triton's landscapes and climates," authored by Tanguy Bertrand, François Forget, and Emmanuel Lellouch, presents findings that suggest the differences in their surface appearances can be primarily attributed to their obliquity, or axial tilt.

Both Pluto and Triton exhibit similar sizes, densities, and compositions, including volatile ices such as nitrogen (N2), methane (CH4), and carbon monoxide (CO). However, their surface characteristics differ significantly. Triton, which is in orbit around Neptune, experiences substantial tidal heating, resulting in a relatively smooth surface due to resurfacing processes. In contrast, Pluto, which does not undergo tidal heating, displays a more rugged topography.

The researchers conducted long-term simulations of volatile transport on both bodies, using identical initial conditions and volatile inventories. Their model successfully replicated the observed distribution of volatile ices on the surfaces of both Pluto and Triton. The results indicate that the differences in obliquity are the main factor influencing the distinct climatic and surface properties of these two worlds.

This research supports the hypothesis that while Pluto and Triton may have originated from similar environments, their divergent evolutionary paths have led to their current differences. The findings could have implications for understanding the climatic evolution of other celestial bodies in the Kuiper Belt and beyond. The full paper can be accessed through arXiv with the identifier arXiv:2409.01122.