ARTEMIS MISSION MODIFICATIONS FOR PLANETARY SCIENCE A PROPOSAL SUBMITTED TO: MISSION OPERATIONS AND DATA ANALYSIS PROGRAM FOR THE PLANETARY OPERATING MISSIONS AUGUST 22, 2009 V. Angelopoulos, THEMIS Principal Investigator, University of California D. G. Sibeck, THEMIS Project Scientist, NASA/GSFC J. Halekas, G. T. Delory, R. Lillis, Space Sciences Laboratory, University of California, Berkeley C. T. Russell, K. Khurana, G. Schubert, Institute of Geophysics and Planetary Physics, UCLA, and R. E. Grimm, Department of Space Studies, Southwest Research Institute, Boulder ARTEMIS MISSION MODIFICATIONS FOR PLANETARY SCIENCE 1. EXECUTIVE SUMMARY .....................................................................................................................................1 2. ARTEMIS (P1 AND P2) CONCEPT...................................................................................................................3 3. PLANETARY SCIENCE WITH ARTEMIS......................................................................................................5 3.1 EXOSPHERE AND PLASMA PICK-UP ....................................................................................................................8 3.2 LUNAR DUST.....................................................................................................................................................10 3.3 DUST TRANSPORT ............................................................................................................................................12 3.4 INTERIOR STRUCTURE AND COMPOSITION OF THE MOON FROM ELECTROMAGNETIC INDUCTION.............12 3.5 SURFACE PROPERTIES AND PLANETARY EVOLUTION AS REVEALED BY CRUSTAL MAGNETISM AND SPACE WEATHERING..........................................................................................................................................................15 3.6 ARTEMIS AND LRO.......................................................................................................................................18 3.7 ARTEMIS AND LADEE..................................................................................................................................19 3.8 ARTEMIS AND INTERNATIONAL LUNAR NETWORK. ....................................................................................19 4. PLANETARY SCIENCE TRADE STUDIES...................................................................................................19 4.1 PERISELENE REDUCTION..................................................................................................................................19 4.2 INCLINATION ADJUSTMENTS............................................................................................................................20 4.3 INSTRUMENT PLANETARY RATES AND MODES ................................................................................................20 5. INSTRUMENT OPERATIONS FOR PLANETARY......................................................................................20 5.1 PARTICLE INSTRUMENT MODE CHANGES ........................................................................................................20 5.2 MAGNETOMETER NOISE REMOVAL .................................................................................................................21 5.3 SHADOW SPIN RATE CHANGES .........................................................................................................................21 6. MISSION OPERATIONS: STATUS AND PLANETARY TASKS..................................................................22 6.1 OBSERVATORY AND INSTRUMENT STATUS ......................................................................................................22 6.2 STATUS OF GROUND SYSTEMS ..........................................................................................................................23 6.3 PRIME MISSION OPERATIONS (FY07/08/09) ....................................................................................................23 6.4 TRANSLUNAR PHASE (FY10) ...........................................................................................................................23 6.5 LISSAJOUS PHASE (Q1,Q2 OF FY11)...............................................................................................................24 6.7 LUNAR ORBIT (LO) PHASE ..............................................................................................................................24 6.8 ARTEMIS MISSION DESIGN AND NAVIGATION .............................................................................................25 6.9 ARTEMIS FLIGHT OPERATIONS AND SCHEDULING .......................................................................................25 6.10 SUMMARY OF MISSION OPERATIONS TASKS .................................................................................................25 8. PRIOR RESULTS, COMMUNITY SUPPORT .................................................................................................26 9. PUBLIC AFFAIRS AND EPO .............................................................................................................................27 9.1 RECENT PUBLIC AFFAIRS ACTIVIVIES ............................................................................................................27 9.2 EPO PLANS.......................................................................................................................................................28 10. REFERENCES (TERSE)....................................................................................................................................28 11. ACRONYMS......................................................................................................................................................30 ADDENDUM: EXPANDED REFERENCE SECTION.........................................................................................31 1. Executive Summary reduce operational complexity. As a result, the probes have orbital and attitude configurations resulting in an ARTEMIS, a two satellite mission to the Moon, operational environment (thermal, power) very similar provides entirely new scientific objectives for the two to that at Earth. Inter-probe separations varying from outermost THEMIS probes. THEMIS, a MIDEX-class 100’s of km to 20RL at lunar distances will enable heliophysics mission comprising five identical probes P1 and P2 to make the first systematic two- satellites (“probes”), was launched on February 17, point observations of distant magnetotail phenomena, 2007 to study magnetospheric substorms, solar wind- with the comprehensive instrumentation needed to magnetosphere coupling and radiation belt electron resolve outstanding heliophysics questions concerning energization (Angelopoulos, 2008). By September not only solar wind and magnetotail phenomena, but 2009, THEMIS will have successfully completed its also the structure and dynamics of the lunar wake at primary objectives, returning observations that are downstream distances ranging from 100s of km to already changing our understanding of magnetospheric 30RL. The Heliophysics Senior Review panel strongly processes. In its proposal to the February 2008 endorsed the ARTEMIS mission concept (although the Heliophysics Senior Review, the THEMIS team funding allocated fell significantly below that proposed an extended mission retaining the three requested), and ARTEMIS operations commenced in innermost probes, P3, P4 and P5, in Earth orbit while the summer of 2009. After several lunar and Earth sending the two outermost probes, P1 and P2, into flybys in early 2010, the ARTEMIS probes are lunar orbit. The rationale for the ARTEMIS concept expected to enter through a low-thrust trajectory the was to conduct cutting-edge heliophysics science with Earth-Moon Lissajous orbits in October 2010 and be the outermost two probes and simultaneously evade inserted into stable, low inclination, highly eccentric terminal shadows anticipated in March of 2010 if the lunar orbits in April 2011. Heliophysics operations spacecraft remained in Earth orbit. Thus ARTEMIS have been approved through 2012. was born, to study “Acceleration, Reconnection, Turbulence and Electrodynamics of Moon’s Interaction with the Sun”. The two ARTEMIS probes, now en-route to the Moon, will be captured into Lunar orbits in April 2011. Figure 1.2 ARTEMIS will study with two identical, cross- P1=TH-B calibrated spacecraft lunar exospheric ions and dust, crustal P2=TH-C magnetism, and the lunar interior. One probe will measure P3=TH-D the pristine solar wind driver, while the other will study the P4=TH-E lunar environment’s response. ARTEMIS extends the P5=TH-A SELENE/Kaguya results into the next decade, while it provides synergy with LRO, LADEE and the International Figure 1.1. THEMIS extended baseline and ARTEMIS. Lunar Network. Insert shows probe number assignments to probe letters, which was done after early checkout. Orbits are publicly From the moment ARTEMIS was conceived, the available for plotting at: http://sscweb.gsfc.nasa.gov/tipsod team realized that significant benefits to planetary For ARTEMIS: ART_1,2; for the Moon click on: “Moon”, and science could accrue from the two lunar probes with for THEMIS P3, P4 and P5 select THEMIS_D,E,A (pred). further, albeit small, orbit and instrument optimizations. Aside from the significant progress JPL mission designers and the ARTEMIS science expected in understanding the lunar wake and team have optimized the ARTEMIS