(a) Lomb–Scargle periodogram for MIRI filter F770W. (b) Lomb-Scargle periodogram for MIRI filter F1800W. The THEM signal is diluted in longer thermal wavelengths. (c) A² as a function of the moon’s orbital period for the 2.5 h variable IPMO and an Earth-sized exomoon with T_h = 1000 K at an edge-on orbit at 3 pc. The dashed and dotted black lines denote FAP = 0.5% and FAP = 80%. The red area shows the stable moon orbit region, between the host’s Roche limit and the Hill sphere.