English

Enhanced thermal radiation from a tidally heated exomoon with a single hot spot

Earth and Planetary Astrophysics 2021-10-27 v2

Abstract

An exomoon on a non perfectly circular orbit experiences tidal heating that is capable to significantly contribute to the thermal brightness of the moon. Here we argue that the thermal heat is unevenly distributed on the moon's surface, the emission of the tidal heat is limited to a few hot spots on the surface. A well-known example is the tidally heated Io. Due to their significantly increased temperature, the hot spots enhance the energy emission in thermal wavelengths. We made simulations using Monte-Carlo method to examine this contribution, and to predict about the possible detectability of such a spotted exomoon. We found that in the case of large, Earth sized companions to jupiters around red dwarf stars exhibit a thermal flux that enables the direct detection of the moon, due to its photometric signal that can exceed \approx100 ppm in the most favourable configurations.

Keywords

Cite

@article{arxiv.2110.05353,
  title  = {Enhanced thermal radiation from a tidally heated exomoon with a single hot spot},
  author = {Zoltán Jäger and Gyula M Szabó},
  journal= {arXiv preprint arXiv:2110.05353},
  year   = {2021}
}

Comments

Accepted by MNRAS, 16 pages