Juno's science planning process: Development and evolution since launch

摘要

NASA's Juno spacecraft arrived at Jupiter on July 4, 2016 after a 5-year interplanetary cruise. In initial concept, Juno's science planning and operations process was extremely simple, with instruments operating in a very repetitive (from orbit to orbit) and non-interactive fashion. That initially simple, non-interactive, planning process has undergone significant changes and enhancements over the course of the project's lifetime, with the most significant changes occurring after launch. Since Juno's launch in August 2011, a new science investigation has been added (the Radiation Monitoring Investigation, which uses Juno's Stellar Reference Units (SRUs) and Jovian Infrared Auroral Mapper (JIRAM) instrument to monitor the Jovian radiation environment), as has a power modeling process that takes into account the details of instrument operation on any given orbit. Additionally, the planned capture orbit was changed from 107 days to two 53.5-day orbits, and the planned science orbit was changed from an 11-day period to a 14-day period. Lastly, a tactical science planning process was developed in order to allow Juno's science teams to make changes to their observation plans from one orbit to the next, a capability that did not exist in the original baseline. Since arrival at Jupiter, the science planning process and timeline has undergone further changes, as the project chose to remain in the 53-day period capture orbit for the entirety of the science mission. In this paper, I will discuss the drivers that led to the significant changes to Juno's initial baseline science planning process that were implemented during cruise, how these new processes were developed, and how they were to be implemented for the instrument teams and the Juno mission system as a whole. Budgetary and human-factor impacts, such as workload considerations, will also be discussed, when applicable. We will discuss the post-Jupiter Orbit Insertion (JOI) change to Juno's science orbit through the lens of science planning and operations, and discuss how the process Juno currently uses was finally settled on.