Planetary Science Summer School

1. Designing a New Frontiers-class Trojan/Centaur Reconnaissance Mission A JPL Planetary Science Summer School Study Breakthrough level of understanding Significant advance in understanding Some advance in understanding Alessondra Springmann1, C. Burke1, M. Cartwright2, R. Gadre3, L. Horodyskyj4, A. Klesh5, K. Milam6, N. Moskovitz7, J. Oiler8, D. Ostrowski9, M. Pagano8, R. Smith10, S. Taniguchi5, A. Townsend-Small11, K. U-yen10, S. Vance12, J. Wang3, J. Westlake13, K. Zacny14 1Massachusetts Institute of Technology, 2University of California, Los Angeles, 3Georgia Institute of Technology, 4Pennsylvania State University, 5University of Michigan, 6Ohio University, 7University of Hawaii Institute for Astronomy, 8Arizona State University, 9University of Arkansas, 10NASA Goddard, 11University of California, Irvine, 12Jet Propulsion Laboratory, 13University of Texas, San Antonio, 14University of California, Berkeley. Planetary Science Summer School Mission Design and Impactors Instruments Subsystems For the last 20 years, the Jet Propulsion Laboratory has sponsored the Planetary Science Summer School (PSSS) to give faculty, postdocs, and graduate students experience in the design and engineering of robotic missions to Solar System bodies of interest to NASA. Mission proposals are based off of recommendations from the NRC’s Decadal Survey. PSSS is a week-long program where students are paired with engineers from JPL’s Team X to concurrently design spacecraft, payload, science instruments, and mission. The baseline mission design requires an Atlas V 531 launch vehicle and allows for three small body encounters. The trajectory brings the spacecraft within 900 km of 2001 HM10, which will provide the opportunity for a test run of the spacecraft systems. During the (624) Hektor encounter the spacecraft passes 700 km above the target at 8.2 km/s, while at 39/P Oterma it passes 800 km above the target at 9.1 km/s. A visualization of the trajectory below shows the orbits of the target bodies in addition to other relevant Solar System objects: Approximately six days prior to encounters with each target, the spacecraft will launch a 75-kg “dead” tungsten ball. Each impact will excavate a crater on the target, exposing the pristine subsurface and also producing a plume of material for analysis, allowing for . Due to concerns of material hitting and damaging the spacecraft, flybys will occur at a height too far away to perform onboard analysis of samples generated in the impacts. The impacts and resulting craters will help determine the extent of weathering on each object. SCIENCE INSTRUMENTS! Configuration Traceability This matrix shows how the mission goals and science questions can be answered by different instruments and measurements, and how the various instrument measurements will increase scientific understanding: Something something something Mission Overview and Objectives Our mission objectives are the in situ reconnaissance of a Trojan asteroid and a Centaurs via conventional passive methods such as imaging and radio science in addition to the launch of two Deep Impact-style impactors (one for the Trojan target and the other for the Centaur target). Why study Jupiter Trojan asteroids and Centaurs? These primitive small bodies hold clues to the origin and evolution of the Solar System, in that they have avoided most of the processing experienced by larger bodies. Trojans were likely captured during Solar System formation, while Centaurs are believed to have originated in the Kuiper Belt and are similar to comets. Trojans and Centaurs are two major populations that have never been explored by spacecraft and have not been exhaustively studied by ground-based telescopes due to being both dim and distant. Centaurs, however, provide an accessible source of material from two more remote populations: the Kuiper Belt and comets. Targets were selected based on their science potential and low V requirements. Our mission involves a launch in 2015, followed by an encounter with main belt asteroid 2001 HM10 in 2016. In 2020, the spacecraft will encounter the Trojan target (624) Hektor, launch a single impactor, then continue on to the Centaur target 39/P Oterma and launch a second impactor. (624) Hektor is a binary D-type Jupiter Trojan with an inclination of 18˚, while 39/P Oterma is a relatively-unstudied Centaur, approximately 30-60 km in diameter. Acknowledgements We would like to thank the JPL Office of Informal Education, Anita Sohus, Amber Norton, Charles Budney, and the rest of Team X. For more information please visit http://pscischool.jpl.nasa.gov