Julia Language 1.1 Ephemeris Reader and Gravitational Modeling Program for Solar System Bodies

Julia is an open-source programming language designed for numerical computing combining simplicity and the ease of dynamic languages with the speed of compiled languages. Julia version 1.0 was released in August of 2018, marking the first stable version of the language.This project has created a software tool capable of retrieving data for major and small bodies, or ephemeris and constant data, which currently does not exist in Julia. Creating such a tool in Julia will provide later projects with a convenient and functional package to automate many tasks in astrodynamics. Using NASA databases, the tool stores information based on user inputs and outputs specific information about a body.The Julia 1.1 version of the tool has resulted in improvements including decreasing the code’s runtime and new gravity field modeling. To model the gravitational fields of major and minor bodies, the code uses spherical harmonics, which are mathematical expansions. The updated version now calculates an additional set of polyhedral harmonics to more accurately represent the field. Using the Database of Asteroid Models from Inversion Techniques (DAMIT) the ephemeris reader can produce three-dimensional models of asteroids. DAMIT provides coordinates for the asteroid, and the reader then utilizes DAMIT to provide an accurate gravitational model. This project will be useful by creating a tool available to users in the open-source Julia language. With faster run time, designers can more efficiently use Julia to their advantage when designing spacecraft trajectories.