The Effect of Planetary Illumination on Climate Modelling of Earthlike Exomoons

Abstract

From analytical studies of tidal heating, eclipses and planetary illumination, it is clear that the exomoon habitable zone (EHZ) - the set of moon and host planet orbits that permit liquid water on an Earthlike moon's surface - is a manifold of higher dimension than the planetary HZ. This paper outlines the first attempt to produce climate models of exomoons which possess all the above sources and sinks of energy. We expand on our previous 1D latitudinal energy balance models (LEBMs), which follow the evolution of the temperature on an Earthlike moon orbiting a Jupiterlike planet, by adding planetary illumination. We investigate the EHZ in four dimensions, running two separate suites of simulations. The first investigates the EHZ by varying the planet's orbit, keeping the moon's orbit fixed, to compare the EHZ with planetary habitable zones. In general, planetary illumination pushes EHZs slightly further away from the star. Secondly, we fix the planet's orbit and vary the moon's orbit, to investigate the circumplanetary inner habitable edge. We demonstrate that an outer edge can exist due to eclipses (rather than merely orbital stability), but this edge may be pushed outwards when the effect of the carbonate-silicate cycle is taken into account.

11 pages, 16 figures, accepted for publication in MNRAS

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Cited by in corpus (7)

• Formation, Habitability, and Detection of Extrasolar Moons
• On the detection of Exomoons: A search in Kepler data for the orbital sampling effect and the scatter peak
• Surface Flux Patterns on Planets in Circumbinary Systems, and Potential for Photosynthesis
• Origin and Stability of Exomoon Atmospheres - Implications for Habitability
• A target list for searching for habitable exomoons
• The subsurface habitability of small, icy exomoons
• An Energy Balance Model for Rapidly and Synchronously Rotating Terrestrial Planets