The New Horizons mission to Pluto and the Kuiper Belt Leslie Young New Horizons Deputy Project Scientist (USA)

Janvier Workshop 3e zone Slide 2 Pluto, Charon, Nix, and Hydra as seen from HST

Janvier Workshop 3e zone Slide 3 Pluto, Charon, Nix, and Hydra as seen in the Louvre

Janvier Workshop 3e zone Slide 4 New Horizons trajectory Pluto-Charon 14 July 2015 KBOs Jupiter System 28 Feb 2007 Launch 19 Jan 2006

Janvier Workshop 3e zone Slide 5 Instrument Payload SWAP Solar wind analyzer PEPSSI Energetic particle detector LORRI Long-range visible imager Ralph visible pan. and color imager, IR spectrometer Alice UV imaging spectrometer REX Radio science & radiometry Star Trackers Guidance and control +Y +X +Z SDC Student dust counter (under spacecraft)

Janvier Workshop 3e zone Slide 6 New Horizons Remote Sensing Instrument Fields of View (-X)

Janvier Workshop 3e zone Slide 7 Ralph/LEISA (Linear Etalon Imaging Spectral Array) Infrared imaging spectrometer 256 x 256 pix, 64 microradian/pixel µm, R≈ µm, R≈240 scanned to form 256 x 256 x n spectral image cube cm cm wavenumber (cm -1 )

Janvier Workshop 3e zone Slide 8 Ralph/LEISA (Linear Etalon Imaging Spectral Array) Infrared Imaging Spectrometer 256 x 256 pix, 64 microradian/pixel µm, R≈ µm, R≈240 scanned to form 256 x 256 x n spectral image cube

Janvier Workshop 3e zone Slide 9 Ralph/MVIC (Multi-spectral Visible Imaging Camera) Four Color Time Delay Integration (TDI) nm nm nm nm 5000 pix, 20 microradian/pixel scanned to form four 5000 x n images

Janvier Workshop 3e zone Slide 10 Ralph/MVIC (Multi-spectral Visible Imaging Camera) Panchromatic Time Delay Integration (TDI) nm 5000 pix, 20 microradian/pixel scanned to form 5000 x N image

Janvier Workshop 3e zone Slide 11 Ralph/MVIC (Multi-spectral Visible Imaging Camera) Panchromatic Framing Array nm 5000 pix, 20 microradian/pixel 128 pix, 20 microradian/pixel 5 km 0.6 km/pix

Janvier Workshop 3e zone Slide 12 LORRI (LOng Range Reconnaissance Imager) High-resolution Imager 1024 x 1024 pix, 5 microradian/pixel nm 0.6 km/pix 0.1 km/pix

Janvier Workshop 3e zone Slide 13 Alice Ultraviolet Long-slit Spectrometer Å "Box" "Slot"" 32 pix (30 active), 0.27°/pixel 1024 pix (780 active), 1.8 Å/pixel nm. FWHM = Å (point source), 172 Å (filled slit) Å. FWHM = Å (point source), 9 Å (filled slit) Pluto's EUV/FUV Line-of-sight Atmospheric Opacity Wavelength (nm) Wavelength (nm) Altitde (km) Pluto Airglow Brightness SNR Model Model Brightness (R)

Janvier Workshop 3e zone Slide 14 January 19, 2006 On our way!

Janvier Workshop 3e zone Slide 15 New Horizons in Flight Ralph/MVIC Imager and IR Spectrograph Ralph pan frame Image of M7: The oddly shaped “blobs” (in rectangles) are energetic particle hits. Digitized Sky Survey image of same field:

Janvier Workshop 3e zone Slide 16 New Horizons in Flight Alice UV Spectrometer Sky background showing Lyman- , the shape of the box and slot, the decrease in flux in the middle of the photocathode gap from 2006 Aug 31.

Janvier Workshop 3e zone Slide 17 New Horizons in Flight REX Radio Science 1.2° full width between 3 dB points Mapping out the High Gain Antenna (HGA)

Janvier Workshop 3e zone Slide 18 New Horizons in Flight LORRI High Resolution Imager

Janvier Workshop 3e zone Slide 19 New Horizons in Flight SWAP Solar Wind Analyzer Solar wind speed, temperature and density variations observed. Three instrument cycles are required for the solar wind to be observed at each energy step. This gives the appearance of the solar wind flux changing over 3 cycles. Speed Changes Day of Year (Oct 17 - Nov 17) Compression & or Shock Increase in temperature, velocity, & number density

Janvier Workshop 3e zone Slide 20 New Horizons in Flight PEPSSI Energetic Particle Detector Counts/bin (log) 1 10 Very good Alpha / proton separation down to 20 keV DOY 172 (June 21) – 2000V

Janvier Workshop 3e zone Slide 21 New Horizons in Flight SDC Student Dust Counter July 14 - August 16

Janvier Workshop 3e zone Slide 22 New Horizons Jupiter Gravity Assist Achieve the Pluto JGA Serve as practice for Pluto-system encounter Do good Jupiter science - Jovian meteorology, satellite geology and composition, auroral phenomena, and magnetospheric physics Jupiter closest approach 2007 February Jupiter radii Press conference 2007 January 18 PEPSSI, LORRI (Jupiter), LEISA (Callisto),...

Janvier Workshop 3e zone Slide 23 New Horizons at Jupiter: Jupiter Meteorology and Aurorae NIR image cubes of storm activity near the GRS Hi-res imaging of the Little Red Spot Global imaging of atmospheric circulation UV stellar occultation UV, NIR scans of polar aurorae and airglow

Janvier Workshop 3e zone Slide 24 New Horizons at Jupiter: Galilean Satellites Visible and NIR imaging of high- temperature volcanic thermal emission on Io Mapping plumes and surface changes on Io Mapping global topography on Europa UV stellar occultations and auroral emission studies of satellite atmospheres NIR mapping of surface composition LORRI MVIC LEISA New Horizons view of Io at closest approach Io atmosphere stellar occultation signature

Janvier Workshop 3e zone Slide 25 New Horizons at Jupiter: Rings and Small Satellites Search for small satellites embedded in the rings Map ring vertical structure during ring-plane crossing Map spatial distribution of “gossamer” rings Determine ring particle phase function Phase function for outer satellites Himalia, Elara

Janvier Workshop 3e zone Slide 26 New Horizons at Jupiter: Magnetosphere Fly down the magnetotail for the first time –Investigate plasma loss mechanisms In-situ plasma measurements in the middle magnetosphere Solar wind observations on approach to complement Earth-based auroral observations High-resolution imaging spectroscopy of the Io plasma torus

Janvier Workshop 3e zone Slide 27 New Horizons at Jupiter: Education/Public Outreach Imaging Imaging of selected scenic alignments between bodies in the Jupiter system

Janvier Workshop 3e zone Slide 28 New Horizons at Pluto Closest Approach 2015 July 14 S/C trajectory time ticks: 10 min Charon orbit time ticks: 12 hr Occultation: center time Position and lighting at Pluto C/A Distance relative to body center Pluto Charon 0.24° Sun Earth 12:40 13:40 11:40 Pluto C/A 11:59:00 11,095 km km/s Charon C/A 12:12:52 26,937 km km/s Pluto-Sun Occultation 12:49:00 Pluto-Earth Occultation 12:49:50 Charon-Sun Occultation 14:15:41 Charon-Earth Occultation 14:17:50

Janvier Workshop 3e zone Slide 29 New Horizons at Pluto: Geology and Geomorphology Young et al 1999 Young et al 2001 Hemispheric panchromatic maps (<0.5 km/pixel) Hemispheric color maps (<5 km/pixel) Phase integrals (moderate and high phase angles) Topography (stereo imaging, photoclimometry) High-resolution terminator images Bolometric Bond albedos (normal reflectance and photometric phase functions)

Janvier Workshop 3e zone Slide 30 New Horizons at Pluto: Geology and Geomorphology Hemispheric panchromatic maps –Encounter hemispheres of Pluto (MVIC) and Charon (MVIC, LORRI) at 0.5 km/pix –Maps of Pluto and Charon at 12-hour intervals from 6 days out at 36 km/pix (LORRI) –Nightside maps of Pluto in reflected Charon-light. 0.4 km/pix (MVIC), resolution depends on SNR Hemispheric color maps (<5 km/pixel) –Redundant four-color maps of Pluto at 0.7 km/pix, of Charon at 1.4 km/pix (MVIC) –Maps of Pluto and Charon at 12-hour intervals from 6 days out at 144 km/pix (MVIC) Phase integrals (moderate and high phase angles) –Phase studies during cruise and approach, 5-15 deg –Pluto at 9 phases ° (attempt at 170°). Charon at 6 phases °. Topography (stereo imaging, photoclimometry) – 1000 km). <5 km heights (at baselines < 250 km) High-resolution terminator images –Pluto: 6-10 images 38x1500 km at 0.30 km/pix (MVIC), x72 km images at 0.07 km/pix (LORRI). –Charon: entire hemisphere at 0.52 km/pix (MVIC), – x143 km images at 0.14 km/pix (LORRI). Bolometric Bond albedos (normal reflectance and photometric phase functions) –Same dataset as phase integrals

Janvier Workshop 3e zone Slide 31 New Horizons at Pluto: Surface Composition Hemispheric infrared spectra ( micron) Spatial distribution of N 2, CO, CH 4 Presence of other volatiles, hydrocarbons, or minerals High spatial resolution spectral images Map surface temperatures wavelength (micron) Douté et al 1999 N2N2 CH 4 CO Grundy and Buie Geometric Albedo

Janvier Workshop 3e zone Slide 32 Hemispheric infrared spectra ( micron) –"Far-side" maps at < 446 km/pixel (LEISA) at /D ≈ 240 ( µm) and /D ≈ 550 ( µm) –Pluto: two maps of approach hemisphere, at 6 and 10 km/pixel (LEISA) –Charon: two maps of approach hemisphere, at 5 and 10 km/pixel (LEISA) Spatial distribution of N 2, CO, CH 4 –Pure N 2 at 2.15 µm, and N 2 :CH 4 from shifts in CH 4 bands at e.g., 2.2 µm –CH 4, CH 4 :N 2, or N 2 :CH 4 at many weak and strong bands throughout Pluto's spectrum –CO at 1.58 and 2.25 µm Presence of other volatiles, hydrocarbons, or minerals –H 2 O at e.g., 2.0 µm. Crystalline form at 1.65 µm –NH 3 or NH 3 hydrate at 2.2 µm –CO 2 at 1.96 µm –C 2 H 6 at 1.68, 2.33 µm. C 2 H 2 at 2.45 µm, C 2 H 4 at 2.22, 2.26 µm, CH 3 OH at 2.28 µm –SO 2 at 2.13 µm, H 2 S at 1.64 µm, HCN at 1.91 µm, HC 3 N at 1.83 µm –Pyroxene at µm, kaolinite-serpentine clays at 1.40 µm, Al-bearing phyllosilicates at µm High spatial resolution spectral images –Pluto: 824 x 333 km scan at 1.3 km/pixel –Charon: 1033 x 486 km scan at 1.9 km/pixel –Color (0.89 µm CH 4 band) maps of Pluto at 0.7 km/pix, of Charon at 1.4 km/pix, and far-side at 144 km/pix (MVIC) Map surface temperatures –Average temperature to 0.1 K at 1340 km or hemispheric averaged resolution (REX, radiometry at 4.2 cm emission) –N 2 temperature to 2.0 K at 56 km resolution (LEISA, Grundy, Schmitt and Quirico 1993, Tryka, Brown and Anicich 1995) –Crystalline H 2 O temperature to 5 K at 40 km resolution (LEISA, Grundy et al. 1999) –Pure CH 4 temperature to 6 K at 96 km resolution (LEISA, Grundy Schmitt and Quirico 2002) New Horizons at Pluto: Surface Composition

Janvier Workshop 3e zone Slide 33 New Horizons at Pluto: Atmospheres Composition (N 2, Ar, CO, CH 4 ; H, H 2, HCN, C x H y ) Pressure, temperature, temperature gradient Hazes and clouds Escape rate Ionosphere Search for atmosphere around Charon after Summers et al 1997 Young et al 2006

Janvier Workshop 3e zone Slide 34 New Horizons at Pluto: Atmospheres Composition (N 2, Ar, CO, CH 4 ; H, H 2, HCN, C x H y ) –Solar occultations, Å, 3.5 Å spectral resoluton, Sun subtending 8 km (Alice) for N 2, CH 4, C x H y, HCN, others –Airglow observations on approach, and nightglow on departure (Alice) for Ar, CO, H, Ne, others –Stellar occultations planned, not yet identified Pressure, temperature, temperature gradient –N 2 line-of-sight number density in the upper atmsphere from solar and stellar occultation (Alice) –N 2 line-of-sight number density in the lower atmsphere from uplink radio occultation, dual DSN sites (REX) Hazes and clouds –Near-surface opacity Å from solar and stellar occultation (Alice) –Low-phase imaging (MVIC, LORRI) –High-phase imaging at < 0.4 km/pixel (MVIC), sensitive to 10% of Triton's haze from surface to 80 km Escape rate –Modelling from temperatures and pressures near 2.5 Pluto radii (Alice). –Scale height of the Lyman-  airglow for H-only escape flux (Alice) –Also SWAP and PEPSSI (next slides). Ionosphere –Electron density from radio occultation (REX) Search for atmosphere around Charon –Search to nbar levels with solar occultation (Alice) –Supporting radio occultaion (REX)

Janvier Workshop 3e zone Slide 35 New Horizons at Pluto: Particles and Plasmas Atmospheric escape rate Solar wind interaction Energetic particle environments Dust enviromment McComas et al 2007

Janvier Workshop 3e zone Slide 36 New Horizons at Pluto: Particles and Plasmas Atmospheric escape rate –Energetic particle flux and composition depends on escape rate (PEPSSI, SWAP) –Distance of interface with solar wind, which is proportional to escape rate (SWAP, PEPSSI) Solar wind interaction –Bow shock, wake effects from direction, spead, and temperature of solar wind (SWAP, PEPSSI) Energetic particle environments –Enegetic pick-up ions likely 1 million km (900 Pluto radii) upsteam of Pluto. PEPSSI and SWAP will measure direction, energy, and mass of energetic particles. Dust enviromment –Interplanetary dust environmet, with the first dust measurements beyond 18 AU (SDC) –Immediate dust environment downstream of the Pluto system (SDC)

Janvier Workshop 3e zone Slide 37 New Horizons at Pluto: Origin and Evolution Orbits Radii, mass, density Additional rings or satellites Magnetic field? Canup ,000 km McKinnon et al 1997

Janvier Workshop 3e zone Slide 38 New Horizons at Pluto: Origin and Evolution Orbits –150 days of resolved images of Pluto, Charon, Nix and Hydra at 15° solar phase angle (LORRI) Radii, mass, density –Masses from orbits of Pluto and satellites around barycenter (LORRI) –Masses from the deflection of New Horizons using Doppler measurements (REX) –Radii and shapes from single 1024x1024 frames Pluto and Charon at 3 km/pixel (LORRI) –Additional shape measurements from the combination of all imaging data (LORRI, MVIC, LEISA) –Additional constraints on the radii from occultation chord lengths (Alice, REX) Additional rings or satellites –Imaging of the entire stability zone at low phase angle (LORRI, MVIC) –High-phase observations (MVIC) Magnetic field? –Not directly addressed by New Horizons. A strong magnetic field may affect the solar wind interaciton (SWAP, PEPSSI).

Janvier Workshop 3e zone Slide 39 Number of accessible KBOs KBO Diam., km at 41 AUFor 200 m/s delta-V Limiting R Magp=0.04p=0.12TotalCold classical (easier to find) 24.0> 160> (13%)0.1 (10%) 25.0> 101> (50%)0.35 (30%) 26.0> 64> (83%)1.1 (67%) 27.0> 40> 234 (98%)2.5 (92%) Based on KBO population statistics from Bernstein et al. (2004). See Spencer et al. 2003, Earth Moon and Planets 92,

Janvier Workshop 3e zone Slide 40 Radial Distribution of Accessible KBOs Strong peak at 42 AU, due to Intrinsic peak there Narrow cone at smaller distances Faintness of more distant KBOs Encounter likely 2018 or 2019 for 115 m/s delta-V

Janvier Workshop 3e zone Slide 41 Search Area, Now and in % of KBOs 85% of KBOs Encounter Locations (2015 Pluto flyby) In the Milky Way at both epochs Search area shrinks with time as it converges on the spacecraft trajectory –Defined by KBO velocity dispersion, not available delta-V

Janvier Workshop 3e zone Slide 42 New Horizons: Exploring the Third Zone For more information (including technical papers), see