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New Horizons: to Pluto and Beyond

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New Horizons: to Pluto and Beyond Why Explore Pluto-Charon Why Explore the Kuiper Belt? New Horizons: To Pluto and Beyond John Spencer New Horizons Science Team SwRI Boulder The Kuiper Belt Astr 4800: “Space Science: Practice and Policy” October 31st 2007 2007 October 31 U. Colorado Astr 4800 Slide 1 2007 October 31 U. Colorado Astr 4800 Slide 2 Pluto-Charon is Scientifically Exciting and Truly Unique Pluto’s Complex Near-IR Spectrum • Pluto is neither a terrestrial nor a gas giant planet: It is a wholly new type: an ice dwarf, common to the deep outer solar system. • Pluto-Charon is the solar system’s only known binary planet, with implications for atmospheric transfer and for better understanding the formation of the Earth- Moon system. • Pluto’s atmosphere is a transitional case between a cometary and a classical planetary atmosphere, and is the only expected site of planetary hydrodynamic escape. • Pluto’s surface consists of a complex mélange of volatile ices (N2, CO, CH4,…) and organics. • Pluto’s surface is among the most variegated and contrasty in the solar system. 2007 October 31 U. Colorado Astr 4800 Slide 3 2007 October 31 U. Colorado Astr 4800 Slide 4 Pluto-Charon & Kuiper Belt Are A Scientific Treasure-Trove Prehistory • Pluto-Charon’s surfaces record the details of outer solar system • NASA and the planetary science community began studying Pluto bombardment. Comparison of Pluto’s cratering record with Charon’s should yield a direct comparison of present-day to the time-integrated missions in the late 1980’s KB impactor flux, down to impactor scales of tens of meters. • Discovery of the Kuiper Belt in 1992 added impetus • The Kuiper Belt is the best “archeological site” to explore mid-stage • An AO for instrument proposals for a JPL-led mission was announced, accretion in the outer solar system. then cancelled, in 2000 • Pressure from the community and the public resulted in re-instatement in early 2001, with a request for proposals for a PI-led mission Rob Staehle, leader of the JPL Pluto mission planning team, with Patsy and Clyde Tombaugh, ~1996 2007 October 31 U. Colorado Astr 4800 Slide 5 2007 October 31 U. Colorado Astr 4800 Slide 6 1 New Horizons: Overview 2001: Proposal Site Visit Science Team: New Horizons was one of the Fran Bagenal consortia proposals submitted Rick Binzel for AO-OSS-01, NASA’s Bonnie Buratti request for flyby mission Andy Cheng Dale Cruikshank proposals to Pluto-Charon and Randy Gladstone the Kuiper Belt. Will Grundy Dave Hinson Mihaly Horanyi New Horizons was selected by Don Jennings Ivan Linscott NASA on 29 Nov 2001, and Jeff Moore funded at $30M for FY2002, Dave McComas we are now completing Phase Bill McKinnon Ralph McNutt B. Scott Murchie Carolyn Porco The 107th Senate and House Harold Reitsema Dennis Reuter funded New Horizons to enter Dave Slater full-scale development in their John Spencer Darrel Strobel FY03 NASA markups. Mike Summers President Bush signed this Alan Stern NASA FY03 funding bill on 20 Len Tyler Leslie Young Feb 2003. 2007 October 31 U. Colorado Astr 4800 Slide 7 2007 October 31 U. Colorado Astr 4800 Slide 8 New Horizons Selected! Full Project Team • SwRI and APL Teamed to Lead the Project: – SwRI to lead science team and payload, serve as PI institution – APL to lead mission development & operations • With Five Major Team Partners: – Ball for RALPH instrument – NASA/GSFC for the LEISA IR focal plane – Stanford for the REX radio science investigation – JPL for DSN, Navigation, CoI support – Boeing as third stage supplier • And a World Class Pluto-Kuiper Belt Science Team: – 25 members, various institutions 2007 October 31 U. Colorado Astr 4800 Slide 9 2007 October 31 U. Colorado Astr 4800 Slide 10 New Horizons Overview ¾ Spacecraft: A heritage-base, highly- redundant systems, and carrying a 300 PEPSSI m/s ΔV budget. Mass: 415 kg. Instrument High Gain Antenna SWAP Instrument ¾Encounters: A five-month Pluto- Charon encounter; then on to explore one or more KBOs. ¾Payload: 6 distinct instruments, plus LORRI ALICE EPO Student Dust Counter. Instrument Instrument Star Trackers RALPH Instrument ¾ Science Performance: Exceeds the AO specs for all Group 1 objectives; meets or exceeds the all Group 2, and 3 of the 4 Group 3 objectives. ¾Cost: ~$150M below the New Frontiers cap (through Phase E). 2007 October 31 U. Colorado Astr 4800 Slide 11 2007 October 31 U. Colorado Astr 4800 Slide 12 2 Measurement Objectives Requirements Flowdown (PKB Science Definition Team) Group 1 Objectives: Characterize the global geology and morphology of Pluto and Charon AO Objectives Map surface composition of Pluto and Charon Characterize the neutral atmosphere of Pluto and its escape rate Group 2 Objectives: Characterize the time variability of Pluto's surface and atmosphere Image Pluto and Charon in stereo Measurement Map the terminators of Pluto and Charon with high resolution Requirements Map the composition of selected areas of Pluto & Charon at high resolution Characterize Pluto's ionosphere and solar wind interaction Search for neutral species including H, H2, HCN, and CxHy, and other hydrocarbons and nitriles in Pluto's upper atmosphere Search for an atmosphere around Charon Determine bolometric Bond albedos for Pluto and Charon Mission Spacecraft Map the surface temperatures of Pluto and Charon Requirements Group 3 Objectives: Requirements Characterize the energetic particle environment of Pluto and Charon Refine bulk parameters (radii, masses, densities) and orbits of Pluto & Charon Search for magnetic fields of Pluto and Charon Instrument Ground System Search for additional satellites and rings Requirements Requirements 2007 October 31 U. Colorado Astr 4800 Slide 13 2007 October 31 U. Colorado Astr 4800 Slide 14 2006 Baseline Mission Design Spacecraft System Redundancy Pluto-Charon Encounter Geometry – Delta Launch 14 July 2015 Charon-Earth Occultation Pluto-Earth Occultation 14:37:44 13:10:47 Charon 14:00 Pluto 13:00 Sun Earth Charon-Sun Occultation 0.24° 14:35:37 Pluto-Sun Occultation 12:00 13:09:57 Charon C/A • S/C trajectory time ticks: 10 min 12:34 • Charon orbit time ticks: 12 hr 26,700 km • Occultation: center time Pluto C/A 13.88 km/s • Position and lighting at Pluto C/A 12:20 • C/A distances are to body centers 11,095 km 13.78 km/s 2007 October 31 U. Colorado Astr 4800 Slide 15 2007 October 31 U. Colorado Astr 4800 Slide 16 Payload Overview Science Fulfillment Traceability: – Ralph VIS/IR imaging & spectroscopy remote sensing Science objectives trace into – Alice UV spectrometer measurement techniques & – REX uplink radio science & passive radiometry. instruments. – LORRI high-resolution (long focal length) imager. – SWAP & PEPSSI particles & plasmas suite. New Horizons meets – Venetia Student Dust Counter or exceeds all PKB Group 1 & Group 2, and 3 of the 4 PKB Group 3 measurement objectives. 2007 October 31 U. Colorado Astr 4800 Slide 17 2007 October 31 U. Colorado Astr 4800 Slide 18 3 New Horizons Instruments New Horizons Spacecraft 2 meters 2007 October 31 U. Colorado Astr 4800 Slide 19 2007 October 31 U. Colorado Astr 4800 Slide 20 Ralph Ralph Internal Features Exit pupil baffle Dichroic MVIC Tertiary Beamsplitter FPA (not to scale) LEISA ~11.75” FPA Secondary Primary Entrance Baffle Tube 2007 October 31 U. Colorado Astr 4800 Slide 21 2007 October 31 U. Colorado Astr 4800 Slide 22 2004: Building 2005: Completing 2007 October 31 U. Colorado Astr 4800 Slide 23 2007 October 31 U. Colorado Astr 4800 Slide 24 4 2005: Testing Late 2005: At the Cape 2007 October 31 U. Colorado Astr 4800 Slide 25 2007 October 31 U. Colorado Astr 4800 Slide 26 • December 11th 2005 2007 October 31 U. Colorado Astr 4800 Slide 27 2007 October 31 U. Colorado Astr 4800 Slide 28 2007 October 31 U. Colorado Astr 4800 Slide 29 2007 October 31 U. Colorado Astr 4800 Slide 30 5 Launch 2006 January 19 14:00 EST • Nearly perfect trajectory • Fastest Earth departure ever (36,000 miles per hour) • Passed Moon’s orbit in 9 hours • Pass orbits of: – Mars on 4/7/2006 – Jupiter on 2/28/2007 – Saturn on 6/8/2008 – Uranus on 3/18/2011 – Neptune on 8/24/2014 • Pluto system encounter on 7/14/2015 2007 October 31 U. Colorado Astr 4800 Slide 31 2007 October 31 U. Colorado Astr 4800 Slide 32 2007 October 31 U. Colorado Astr 4800 Slide 33 2007 October 31 U. Colorado Astr 4800 Slide 34 2007 October 31 U. Colorado Astr 4800 Slide 35 2007 October 31 U. Colorado Astr 4800 Slide 36 6 New Horizons Trajectory New Horizons Jupiter Encounter Encounter Closest CA Distance = 32 RJ Approach at: 2007 Feb 28 05:43:40 UTC Gravity Assist • NH Jupiter encounter objectives • International Observing Campaign 1. Gravity Assist - Hubble, Chandra, XMM 2. Stress test for Ops Team - Rosetta, MRO (HIRISE) 3. Calibration Observations - IRTF, Gemini, Subaru, KPNO, VLT, 4. Jovian system science AAT -Amateurs 2007 October 31 U. Colorado Astr 4800 Slide 37 2007 October 31 U. Colorado Astr 4800 Slide 38 • Images at 10 hour and 15 minute intervals, to track large-scale and small-scale motions • Cheng et al. 2007, Science, in press 2007 October 31 U. Colorado Astr 4800 Slide 39 2007 October 31 U. Colorado Astr 4800 Slide 40 Mapping NH3 Clouds with LEISA NH3 Cloud Evolution • Multiple image cubes of GRS region with LEISA Spectral Cube of Jupiter (Spencer) • Reuter et al. 2007, Science LEISA • 3-D cloud movies • Follow up on Galileo discovery of NH3 ice clouds NW of GRS • This region was unusually tranquil, but there were other turbulent regions where NH3 upwelling observed • NIMS Reference Spectrum Average LEISA Spectrum One NH3-rich pixel (circled) NH3 band 1.94/1.99 ratio R = 2.05 NH3 band depth G = 1.60 B = 1.94/1.99 2007 October 31 U.
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