NEW HORIZONS NASA’s Pluto-Kuiper Belt Mission: “The First Mission to the Last Planet”

Major Project Milestones Proposal – Jan-Sep 2001 Phase A Study Complete – Oct 2001 Selection Announcement – Nov 2001 Phase B Start – Jan 2002 Requirements Review (SRR) – May 2002 Preliminary Design Review (PDR) – Oct 2002 Non-Advocate Review (NAR) – Dec 2002 Phase C/D Start – Apr 2003 Critical Design Review (CDR) – Oct 2003 Instrument Deliveries – July 2004-Mar 2005 Integration & Test – Aug 2004-May 2005 Environmental Test – May-Aug 2005 Ship to Cape – 23 Sep 2005 Launch Readiness Review – 11 Dec 2005 Launch Window Opens– 11 Jan 2006

Great Progress is Fundamentally Limited Until We Visit This is the fundamental exploration lesson of planetary science. Pluto at Best HST Resolution Triton at Best HST Resolution Earth’s Moon at the Same Resolution

Pluto: A Little Background Pluto was discovered in January-February 1930, by Clyde Tombaugh at Lowell Observatory, Arizona. Pluto is a Small, Distant World <1% Mars’s Max Apparent Diameter (0.1 arcsec) And 50,000 times fainter than Mars (V~14)

Pluto: A Misfit Orbit? Distance from the Sun varies from 30 to 50 AU Orbital Period: 248 years Eccentricity: 0.25 Inclination: 16 deg

Pluto: Some Basic Properties Rotation Period: 6.4 days (retrograde) Axial Tilt (obliquity): 118 deg Mass: 0.2% Earth’s (1.5x1025 gm) Diameter: 18% Earth’s (1180 km) Reflectivity: 50% (due to its icy surface) The Best Hubble Images of Pluto Are Still Crude

Major Breakthroughs Began In the 1970s N2 and CO ices were later discovered. The CH4, N2, CO distribution is patchy. But N2 dominates almost 10:1 True Color Map

And Continued Through The 1980s and 1990s Pluto’s surface temperature has been measured from Earth and from Earth orbit. The temperature expected for typical Plutonian surfaces warmed by the Sun at 30 AU is just 55 K. Pluto’s surface has been found to exhibit both warm units near 60 K and cold units near 35 K.

Pluto’s Atmosphere Pluto has an atmosphere; it was definitively detected in 1988 by a refractive signature seen in a stellar occultation. It is composed of N2, CO, and CH4, plus trace species; there is evidence for hazes. The atmosphere is thought to be escaping to space hydrodynamically. An occultation in 2003 revealed distinct structural and pressure changes.

The Discovery of Pluto’s Moon: Charon Charon was discovered, by accident, in July 1978 by Jim Christy of the U.S. Naval Observatory. Charon is in synchronous orbit ~19,400 km from Pluto, and spin-spin-orbit locked with a 6.4 day period. 0.9 arc-sec

Pluto: A Clear Outlier Among A Dwarf Planet and A True Binary World The Giant Planets A Dwarf Planet and A True Binary World Charon’s radius is 50% of Pluto’s. Charon’s mass is about 10% of Pluto’s.

And Do Not Judge This Book By Its Cover From the Densities of Pluto and Charon, One Can Derive Crude Interior Models. Pluto is a primarily rocky, not icy body!

Your Father’s Solar System Featured Misfit Pluto Until the 1990s, Pluto was considered a planetary oddity, not fitting in the larger architecture of the solar system.

Revealed Pluto’s Context But the 1990s Clearly Revealed Pluto’s Context The Kuiper Belt

The Discovery Of the Kuiper Belt 1992– Jewitt & Luu found a 100 km sized object in a near-circular orbit, well beyond Pluto. 1993– 4 more KBOs found. 1994– 10 KBOs found. 2005– Over 1000 KBOs are now known.

The Kuiper Belt Over 140,000 KBOs predicted with diameters >100 km, orbits 30-50 AU (assuming 4% reflectivity). Billions of smaller comets are also predicted to exist there. The largest KBOs are well over 2000 km in diameter. Three Orbit Types: Plutinos– Neptune resonant, a<50 AU Classical– Non-resonant, a<50 AU Scattered– Distant (a>50 AU), Neptune ejected

Large KBOs Abound The large KBOs are planetary embryos. These objects reached the mid-stage of planetary accretion. They are dwarf planets.

As Do KBO Satellites Pluto/Charon was only the first binary object (1978). Next up: 1998 WW31 (2001). 16 KBO binaries discovered so far (late 2004). Implication: >20% of all KBOs have satellites.

Pluto-Charon: A Treasure Trove for Science 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 provides the only likely site of planetary hydrodynamic escape, the process believed to have shaped Earth’s primordial atmospheric loss. Pluto-Charon’s surfaces record the detailed history of outer solar system bombardment. The Kuiper Belt is also the best archeological site to explore mid-stage accretion in the outer solar system.

A Reconnaissance Expedition To the Kuiper Belt & Pluto-Charon Toward New Horizons The Highest Priority New Frontiers New Start Recommendation of the NRC’s 2002 Planetary Decadal Survey A Reconnaissance Expedition To the Kuiper Belt & Pluto-Charon

NASA-Specified Pluto-Charon Measurement Objectives Required Important Desired

Proposal Phase Science Team: Alan Stern, PI/SwRI Fran Bagenal/ U. Colorado Rick Binzel/MIT Bonnie Buratti/JPL Andy Cheng/APL Dale Cruikshank/NASA Ames Randy Gladstone/SwRI Will Grundy/Lowell Dave Hinson/Stanford Mihaly Horanyi/U. Colorado Don Jennings/NASA Goddard Ivan Linscott/Stanford Jeff Moore/NASA Ames Dave McComas/SwRI Bill McKinnon/Washington U. Ralph McNutt/APL Scott Murchie/APL Carolyn Porco/SSI Harold Reitsema/Ball Aerospace Dennis Reuter/NASA Goddard Dave Slater/SwRI John Spencer/SwRI Darrel Strobel/Johns Hopkins Mike Summers/GMU Len Tyler/Stanford Hal Weaver/APL Leslie Young/SwRI New Horizons was proposed to AO-OSS-01, NASA’s January 20, 2001 request for flyby mission proposals to Pluto-Charon and the Kuiper Belt. New Horizons was selected by NASA on 29 Nov 2001.

The Initial Reconnaissance of The Solar System’s A Historic Journey The Initial Reconnaissance of The Solar System’s “Third Zone” KBOs 2016-2020 Pluto-Charon July 2015 Jupiter System March 2007 Launch Jan 2006

Project Philosophy Offer early and highly-leveraged science. Do so on time, within budget, and at low risk. Provide Intensive Public Outreach Keep It Simple

Launch Vehicle: Atlas V 551 With A STAR-48 Upper Stage Centaur Interstage Adapter (12.5 ft Dia) CCB Cylindrical Interstage Adapter RD-180 Engine Common Core BoosterTM (CCB) Single RL10 Engine Centaur Upper Stage 5-meter Short Payload Fairing (68 ft) Solid Rocket Boosters Aft Transition Skirt/Heat Shield 5-Meter Payload Fairing Boattail Aft Stub Adapter Centaur Forward Load Reactor Payload Adapter (PLA) Centaur Conical

Instrument Payload REX LORRI ALICE PEPSSI RALPH SWAP CORE: REX radio science & radiometry RALPH VIS/IR imaging & spectroscopy ALICE UV imaging spectroscopy Supplemental: LORRI High-resolution imager SWAP plasma spectrometer PEPSSI energetic particle spectrometer SDC EPO Student Dust Counter SWAP Student Dust Counter

The Student Dust Counter: A New Kind of EPO EPO Goal: Give students a chance to design, build, operate, & study data from a planetary flight experiment. Science Goal: Make the first dust density & size spectrum observations beyond 18 AU. Students have the primary responsibility for the design and development of the SDC; over 35 “first generation” students were involved at CU, with dozens more participating across the U.S. Four Generations of Students To Be Involved. SDC Student Team Leaders

Spacecraft Block Diagram

Launch Windows Overview 2006 Primary Jan 11-Feb 14 Jan ‘06 Window: 34 days C3: 164 km2/s2 Earliest Arrival 2015 2007 Backup 02–15 Feb ‘07 Window: 14 days C3: 166 km2/s2 Earliest Arrival 2019 Requires KBO Fuel Removal New Horizons will be launched from Cape Canaveral, Florida in early 2006. It will be the fastest spacecraft ever launched. NH Star 48B Atlas V

Jupiter Flyby Objectives Gravity Assist (Speed Trajectory to Pluto) Encounter Ops Practice Instrument Calibrations Jupiter System Science C/A Date 10–14 Mar 2007 Range 38–39 RJupiter The New Horizons approaches Jupiter more than three times closer to Jupiter than Cassini did.

Jupiter Flyby Science Jupiter science will include studies of Jovian meteorology, satellite geology and composition, Auroral phenomena, and magnetospheric physics.

New Horizons Will Yield Dramatic Results at Pluto-Charon Triton from Voyager Triton and Pluto at Best HST Resolution

Pluto-Charon Encounter Highlights Six months of encounter science. Exceed Hubble resolution for months. Map all of Pluto and all of Charon. Make global composition maps of Pluto and Charon. Map their surface temperature fields. Directly measure Pluto’s escape rate and assay its atmospheric structure and composition. Improve interior models and determine if either Pluto or Charon differentiated. Locate additional Pluto-system satellites <1 km in diameter. The most exciting discoveries will likely be the ones we Don’t anticipate.

Selected New Horizons KBO Science Geologic, Photometric, Color Mapping Composition Maps (H2O,CO,CO2,CH4,..) Stereo Surface Mapping Thermal Mapping Atmosphere Search Measure Sputtering Products Mass, Density, Figure Measurements Crater Counts for Impactors <20 m in Size Satellite Searches to <1 km, with Follow-up Studies

New Horizons at the Cape

Atlas V-010 in Denver

Mission Status Summary Project Element Status Spacecraft GO Payload RTG Atlas V STAR-48 PI & Science

Toward New Frontiers New Horizons is Demonstrating That Exciting, Lower Cost Outer Planet Missions Are Indeed Feasible.

We Aim to Make This 1990 U.S. Stamp Obsolete And One More Thing We Aim to Make This 1990 U.S. Stamp Obsolete

Someday, Hopefully

A Historic Journey of Exploration