Physical nature of low-contrast coma features

Determine the physical nature of the low-contrast jet-like enhancements observed in the post-perihelion coma of interstellar comet 3I/ATLAS, distinguishing among localized dust emission, viewing-geometry effects, superposed dust populations, nucleus rotation, and projection effects.

Background

Post-perihelion imaging of 3I/ATLAS reveals low-contrast, jet-like enhancements in the coma, including anti-sunward and southern structures whose apparent prominence and orientation vary between observing epochs. Similar features have been reported inconsistently in other observations, with some studies identifying faint jets and others finding no convincing evidence for them.

The paper notes that the observed structures could arise from localized regions of enhanced dust emission, changing viewing geometry, nucleus rotation, or projection effects. Their physical interpretation is therefore unresolved and would require a more detailed analysis than is provided in the study.

References

The enhanced images reveal some low-contrast jet-like enhancements, although their physical nature cannot be established unambiguously.

— Multi-Wavelength Post-Perihelion Polarimetry of Interstellar Comet 3I/ATLAS  (2609.04932 - Gray et al., 4 Sep 2026) in Section 3.3, “Coma morphology”