In blue, the spectral power (spectral radiance integrated over solid angle and area) coming from the hotter ring of P63 (at 900 K); in red, the spectral power coming from the colder but much larger crust (at 230 K). The area for the crust is ∼500 km² (as described in the main text); the area for the hotter ring is inferred from the measured M-band power, as in A. Mura et al. (2024a) and F. Tosi et al. (2025). The blue area represents the integrated signal captured in the M band of JIRAM (or any other instrument working in the 4.5–5 μm range). Adapted from F. Tosi et al. (2025) for the case of P63.