APPLE: An Evolution Code for Modeling Giant Planets

TL;DR

APPLE is a specialized planetary evolution code that integrates advanced equations of state and features to model the complex interior and atmospheric processes of giant planets and exoplanets.

Contribution

It introduces a comprehensive, purpose-built code with novel features for modeling giant planet evolution, including detailed interior and atmospheric processes.

Findings

Incorporates state-of-the-art equations of state for hydrogen, helium, ice, and rock.

Models helium rain and hydrogen/helium immiscibility.

Provides self-consistent atmospheric boundary conditions with spectra and albedos.

Abstract

We introduce APPLE, a novel planetary evolution code designed specifically for the study of giant exoplanet and Jovian planet evolution in the era of Galileo, Juno, and Cassini. With APPLE, state-of-the-art equations of state for hydrogen, helium, ice, and rock are integrated with advanced features to treat ice/rock cores and metals in the gaseous envelope; models for helium rain and hydrogen/helium immiscibility; detailed atmosphere boundary tables that also provide self-consistent albedos and spectra; and options to address envelope metal gradients and stably-stratified regions. Our hope is that these purpose-built features of APPLE will help catalyze the development of the next generation of giant exoplanet and Jovian planet evolutionary models.