A Journey To The Pluto System, A Journey To The Pluto System, And Beyond Adriana Ocampo NEW HORIZONS

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

NEW HORIZONS How Did We Get To Do This?

The New Horizons Team

Persistence Does Pay

NEW HORIZONS 1 Astronomical Unit (AU) = meter stick for Astronomers 1AU = miles AU to Pluto

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

At Kennedy Space Center: November 2005

New Horizons Firsts  First mission to Pluto  First since launch Voyager in 1977 to an unexplored planet  First mission to explore a iced dwarf double planet  First mission to study Kuiper Belt Objects  Fastest space mission ever launched  First planetary mission to carry a student built instrument

Planets Turn Out To Come In Many Sizes

A Lone Misfit? The Old View: 4 Terrestrial Planets 4 Giant Planets 1 Misfit Pluto

Hardly! Misfit Not, Pluto’s Abound The New View: 4 Terrestrial Planets 4 Giant Planets Perhaps 1000 Dwarf Planets

LOTS OF PLANETS!

Best HST Images  Strong Surface Variegation  Polar Features  Stern, Buie, & Trafton (1997) HST Observations (1994): True Color Map (Young et al.)

Pluto’s surface contains at least three volatiles, each with different physiochemical properties. Pluto’s Composition  CH 4 discovered  N 2 and CO ices were discovered in the 1990s.  The CH 4 and CO distribution is patchy.  N 2 dominates ~10:1.  First detected in 1985 and 1988 by a clear refractive  signature, seen in stellar occultations; the surface pressure is ~10 μbar.  N 2, CO, & CH 4, plus trace photo- chemical species.  Evidence for haze and/or temperature T(z) struture.  Strong seasonal effects are expected.  The atmosphere is likely hydrodynamically escaping, several km of ices lost in 4 Gyr.

And At Least Five Moons P4=Kerberos P5=Styx +

PLUTO’s MOONS TO SCALE

A giant impact origin for Pluto- Charon was first suggested in the 1980s (McKinnon 1984, 1989). Satellite Origin Like Earth The giant impact was further strengthened by the discoveries of Nix and Hydra in co-planar orbits to Charon. Numerical models seem incapable of plausibly producing Charon otherwise (Stern, McKinnon, & Lunine 1997; Canup 2005).

Flight Plan

2007: Jupiter Flyby Jupiter science included studies of Jovian meteorology, satellite geology and composition, Auroral phenomena, and magnetospheric physics. C/A Date28 Feb 2007 Range32 R Jupiter

Jupiter Objectives

Volcanoes and Rings

Then, Farewell Jupiter

Pluto -63 days and counting!  Jan-Mar: Observatory Phase  April: Begin Encounter  14 July: Closest Approach  Aug-Mid-2016: Downlink

At Closest Approach 0.24° Sun Earth Hydra Pluto Nix Charon New Horizons Trajectory Pluto C/A 11:50:00 13,695 km km/s Charon C/A 12:04:00 29,432 km km/s Pluto-Sun Occultation 12:51:28 Charon-Sun Occultation 14:17:50 Charon-Earth Occultation 14:20:09 Pluto-Earth Occultation 12:52:30 15:00 11:00 S/C trajectory time ticks: 10 min Occultation: center time Position and lighting at Pluto C/A Distance relative to body center Orbit Period a Charon 6.4 d 19,571 km Nix24.9 d48,675 km Hydra 38.2 d64,780 km 12:00 13:00 14:00 CLOSEST APPROACH 7:50 AM EDT 8509 miles 31,317MPH

Revolutionary Datasets Are In Store  Six months of encounter science.  Exceed Hubble resolution for months.  Map Pluto and all its satellites.  Make composition maps of Pluto & Charon.  Map surface temperature fields.  Measure Pluto’s escape rate.  Assay Pluto’s atmospheric structure and composition.  Determine if either Pluto or Charon differentiated. But the most exciting discoveries will likely be the ones we don’t anticipate.

So Anticipate Dramatic Results! Triton & Pluto At Best HST Resolution Triton from Voyager

Then On To KBOs

Explore Pluto with New Horizons: July

BACKUP SLIDES

Beyond Pluto: KBO The Kuiper Belt is a disc-shaped region of icy objects beyond the orbit of Neptune -- billions of kilometers from our sun. Pluto and Eris are the best known of these icy worlds. There may be hundreds more of these ice dwarfs planets out there Oort cloud region of long term comets

Pluto is a primarily rocky, not icy body! From the Densities of Pluto & Charon, One Can Derive Crude Interior Models DON’T JUDGE THIS BOOK BY ITS COVER

 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.  Charon’s surface is covered in H 2 O-ice; there is as yet no detected atmosphere. 0.9 arc-sec PLUTO’S LARGE MOON: CHARON

INSTRUMENT PAYLOAD

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