A geophysical model for 55 Cancri e

55 Cancri e is one of the closest known super-Earths, orbiting a bright host star that makes it a tantalizing prospect for observations. Measurements of the planet's phase curve and secondary eclipse suggest a possible lava world with >1000 K temperature contrast from day to night. Observations have failed to detect water vapor or signs of escaping hydrogen, consistent with a planet lacking most of the cosmically abundant volatiles. However, the mass and radius measurements likely require a relatively significant atmosphere. Observations have found hints of Na and Ca⁺ in an extended exosphere, which may be consistent with the lava world interpretation, but other measurements suggest the presence of HCN, which would likely require a much more volatile-rich atmosphere. In this presentation, we will review the models that have been proposed for 55 Cnc e and which observations those models are consistent with. We will propose two preliminary models, depending on either the presence or absence of HCN, that are consistent with both mass-radius constraints, as well as atmospheric composition and heat redistribution properties.