New Horizons Update. SBAG Meeting Jan. 12 Tucson. Will Grundy. New Horizons Composition Science Theme Team Lead

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1 New Horizons Update SBAG Meeting 2017 Jan. 12 Tucson Will Grundy New Horizons Composition Science Theme Team Lead

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3 Pluto System Science: The Future Many more manuscripts undergoing review, in draft form, or planned for 2017 Gap analysis driven roadmap for analysis and publishing Increasing levels of community activity (both in collaboration with NH team and as independent efforts) NF-DAP R&A program (step 1 deadline is Feb. 8) New UofAZ Press Space Science Series book approved (meeting to be summer 2019 at APL, with LPI handling abstracts, registration, etc.) Opens the path for completely new science, new missions ( Flyby, Orbit, Land, Rove, and Return Samples... ) 3

4 Pluto System Data Transmission finally completed November 2016 Now working to erase spacecraft SSRs to make room for new data (after careful data reviews, both by instrument teams and by science team) Mid-way through 4 planned deliveries to PDS Small Bodies Node, all on schedule 4 1st delivery (spring 2016) was data transmitted back during the encounter time-frame (through end of July 2015) 2nd delivery (fall 2016) was data downlinked through end of 2015, includes many of the crown jewel data sets These are already available to the public including NF-DAP proposers 3rd delivery (April 2017) 4th and final Pluto delivery (fall 2017) will include higher level products (CODMAC 4/5)

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6 Kuiper Belt Extended Mission Extended mission proposal approved by NASA mid-2016 Runs through 2021 (driven by data rates after 2014 MU69 encounter being even slower than after Pluto) 8 new Co-Is replace a comparable number of departing Pluto-specific Co-Is Dan Britt (UCF) J.J. Kavelaars (UBC) Alex Parker (SwRI) Simon Porter (SwRI) Silvia Protopapa (UMD) Kelsi Singer (SwRI) Peter Thomas (Cornell) Amanda Zangari (SwRI) Extensive community input Workshops at DPS meetings Weekly calls with interested ground-based observers Webex meetings to solicit creative measurement ideas Plasma, dust, and UV measurements already happening: transect through the Kuiper belt Observations of KBOs are underway, too First paper already published Porter et al ApJ 828, L15 6

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8 2014 MU69 Encounter Planning Process Effort being led by John Spencer (SwRI) Finalize science objectives and program level requirements, with traceability to 2011 Decadal science questions Express in terms of Measurement Techniques (MTs), each with a champion Include backup and alternate observations wherever possible Reviewed by Science team, SciOps, PI Trade studies using strawman sequences to optimize MU69 encounter geometry (c/a distance and B-plane position), in consultation with Nav, SciOps, MOPS Use the MTs to generate Science Activity Plans (SAPs) in the SciPlan system Assemble SAPs into de-conflicted timelines, in consultation with MOPS Separate planning of inner core ±1 day (which depends sensitively on C/A distance) and outer core (which does not, and thus can be done first) Plan two separate inner core sequences, with the more distant one in reserve in case of unexpected hazard or worse positional uncertainties than anticipated (can switch to it as late as ~10 days before C/A) Reviewed by Science team, SciOps, PI Science team reviews each timeline SciOps implements the sequences, in consultation with the science team 8 Validate via simulator runs Encounter starts next year!

9 New Horizons Science Objectives (Group 1) 9

10 New Horizons Science Objectives (Group 2) 10

11 New Horizons Science Objectives (Group 3) 11

12 2014 MU69: What We Know About It Typical cold-classical orbit Heliocentric distance at encounter: 43.3 AU Opposition R-band magnitude: V-band absolute magnitude: 11.1 Color: probably red like larger CCs (but very uncertain) Likely V-band geometric albedo range 0.04 (comets) (larger cold classicals) Likely diameter 40 km (albedo 0.04) - 21 km (albedo 0.15) Lightcurve amplitude: magnitudes Rotation period: unknown (more info summer 2017) Satellites: none > 2500 km separation for brightness ratio < 2:1

13 2014 MU69: Occultation Opportunities Valuable for heliocentric orbit improvement Debris / satellite / ring search Size and shape constraints Challenging observations, since MU69 shadow is small and its ground track is uncertain Dense picket fence of observers SOFIA s ability to relocate in the final hours is valuable

14 Strawman Core Observation Plan 3000 km c/a distance, dayside, with ± 180 seconds for TOF knowledge uncertainty Turn time and memory allocation time included LORRI used only while scanning mode, for maximum efficiency LEISA near-ir compositional maps, best resolution 1.0 km/pixel Best MVIC color 490 m/pixel Higher-resolution color might be possible, but requires other trades Alice (FUV/EUV) observations of surface and to search for outgassing REX disk-integrated day and night thermal emission MU69 Direction of S/C motion 0 K s 0s K s K s K s K+ 10,000 20,000 CA12_Alice -20,000-10,000 0 Distance Along Trajectory, km CA11_LORRI CA10_REX CA10_Alice CA09_MVIC PAN CA09_LORRI CA08_MVIC PAN CA08_LORRI CA07_LORRI 14-30,000 CA06_LEISA CA06_LORRI -40,000 CA05_MVIC COL CA05_LORRI -10,000 CA04_REX CA04_Alice n irectio Sun D CA03_LEISA CA03_Alice CA02_LEISA CA02_LORRI CA01_Alice Distance Perpendicular to Trajectory, km Trigger mode can limit data volume and allocation time LORRI scans during flyback provide additional data LORRI rider at close approach has 25 m/pixel resolution

15 0s K s K+ K s K s CA12_Alice CA11_LORRI CA10_REX CA10_Alice CA09_MVIC PAN CA09_LORRI CA08_MVIC PAN CA08_LORRI 20,000 0s K s K+ K s K s K s CA12_Alice 0 CA11_LORRI CA10_REX CA10_Alice CA09_MVIC PAN CA09_LORRI CA08_MVIC PAN CA08_LORRI CA07_LORRI CA06_LEISA CA06_LORRI CA05_MVIC COL CA05_LORRI CA04_REX CA04_Alice K s MU ,000-20,000-10,000 0 Distance Along Trajectory, km -30,000-40,000 CA03_LEISA CA03_Alice CA02_LEISA CA02_LORRI CA01_Alice -10,000 n irectio Sun D CA07_LORRI CA06_LEISA CA06_LORRI CA05_MVIC COL CA05_LORRI CA04_REX CA04_Alice CA03_LEISA CA03_Alice -10,000-10, ,000-20,000 0 Distance Along Trajectory, km -30,000-50,000-40, ,000 CA02_LEISA CA02_LORRI 15 CA01_Alice 10,000 n irectio S un D 0 MU69 Distance Perpendicular to Trajectory, km C/A = km, TOF err = 840 s 0 Distance Perpendicular to Trajectory, km Backup Core Observation Plan 10,000 km close approach, ± 840 second TOF coverage

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17 Summary of Best Observations Green rows are for 10,000 km backup trajectory Some variation in geometry with actual TOF position of MU69 17

18 Backups Slides

19 Decadal Traceability, 1 19

20 Decadal Traceability, 2 20

21 Master Observation List Used to estimate resources, including thruster cycles, fuel, and data volume, for the proposed observations 21

22 Hazard Avoidance Relevant radii Last hazard images at K-18 days have spatial resolution 450 km/pixel Insufficient to resolve a Chariklo-sized ring Sufficient to resolve objects at expected flyby distance Several days required to see orbital motion Nominal flyby distance = 3000 km Chariklo ring radius = 400 km Hill sphere diameter = 73,000 km (for diam=32 km, rho=0.5 g cm -3) Szebehely stability radius = 24,000 km Object at 4 pixel orbital radius at K-18 will have a period of 232 days, so moves 0.1 4x4 pixel/day along orbit and 0.3 pix/day due to decreasing range Current hazard plan: K-30 days: K-20 days 22 1 visit, 2 roll angles, second images each roll (200 images total) Single pointing (covers entire Hill sphere) SNR=7 on ~8 km diameter object with 9% albedo at each roll angle Note that OpNav has 12 images per day on 3 successive days, so this hazard plan is only ~2x deeper than the OpNavs 1 visit, 2 roll angles, second images each roll (200 images total) Single pointing covers most of Hill sphere SNR=7 on ~5 km diameter object with 9% albedo at each roll angle

23 MU69 Flyby: Distant Imaging OpNav Expect first detection in stacks of second 4x4 LORRI images at ~K-100 days, based on scaling from first detection of Pluto small satellites First detection in 0.15-second 1x1 LORRI images at ~K-6 days Satellite/Ring Search Nested 2x2 mosaics on approach, K-28 K-0.9 Cover entire Hill Sphere at start Objects as small as 0.2 km up to 4000 km radius at end Departure 2x2 mosaics for ring, coma, search 23

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