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Scott Bolton OPAG February 1, 2016 Juno Status

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Scott Bolton OPAG February 1, 2016 Juno Status Scott Bolton OPAG February 1, 2016 Juno Status Launched August 2011 Earth flyby October 2013 Jupiter arrival July 4, 2016 Spacecraft is healthy and all instruments are working. Juno Science Juno Science Objectives Origin Determine the abundance of water and place an upper limit on the mass of Jupiter’s dense core to decide which theory of the planet’s origin is correct Interior Juno Instruments Understand Jupiter’s interior structure and how material moves deep within the **** Gravity Science (JPL, ASI) planet by mapping its gravitational and **** Magnetometer— MAG (GSFC) magnetic fields **** Microwave Radiometer— MWR (JPL) **** Jupiter Energetic Particle Detector— JEDI (APL) Atmosphere **** Jovian Auroral Distributions Exp.— JADE (SwRI) Map variations in atmospheric composition, temperature, cloud opacity **** Plasma Waves Instrument— Waves (U of Iowa) and dynamics to depths greater than 100 **** UV Spectrometer— UVS (SwRI) bars at all latitudes **** Infrared Camera— JIRAM (ASI) **** Visible Camera— JunoCam (Malin) Magnetosphere Characterize and explore the three- dimensional structure of Jupiter's polar magnetosphere and auroras. Spacecraft & Payload SPACECRAFT DIMENSIONS JunoCam Diameter: 80 feet (20 meters) Height: 15 feet (4.5 meters) UVS Waves (2 detectors) JEDI JIRAM (6 sensors ) JADE Gravity Science (4 sensors ) (2 sensors) Magnetometer (2 sensors, 4 support cameras) MWR (6 sensors ) Microwave Radiometer (MWR) Experiment The microwave antennas are distributed around the spacecraft and view perpendicular to the spacecraft spin axis off-nadir view emission θ angle nadir view 120° Field of A6: horn View Along-track scanning A3 - A5: slot arrays A1: patch array A2: patch array Sensing the deep atmosphere Juno’s Microwave Radiometer measures thermal radiation from the atmosphere 1000 atmospheres pressure (~500-600km below the visible cloud tops). Determines water and ammonia abundances in the atmosphere all over the planet Sensing the deep atmosphere Juno’s Microwave Radiometer measures thermal radiation from the atmosphere to as deep as 1000 atmospheres pressure (~500-600 km below the visible cloud tops). Determines water and ammonia abundances in the atmosphere all over the planet Synchrotron radio emission from the radiation belts makes this kind of measurement impossible from Earth Atmospheric Dynamics Radiometry investigates atmospheric structure Gravity investigates differential rotation 11 Mapping Jupiter’s gravity Tracking changes in Juno’s velocity reveals Jupiter’s gravity (and how the planet is arranged on the inside). Precise Doppler measurements of spacecraft motion reveal the gravity field. Tides provide further clues. Polar Magnetosphere Exploration Location is Key: Juno passes directly through auroral field lines. A suite of instruments are used to understand the physics: JADE, JEDI, MAG, Waves, JIRAM, UVS “Science In A Fishbowl” http://missionjuno.swri.edu click on “Junocam” 15 Fly along with Juno Juno is part of NASA’s 3D interactive, Eyes on the Solar System… solarsystem.nasa.gov/eyes backup Juno Payload X and Ka Band Gravity Science (JPL/ASI) Magnetometer— MAG/ASC (GSFC/DTU) Microwave Radiometers— MWR (JPL) Energetic Particle Detectors—JEDI(APL) Jovian Auroral Distributions — JADE (SwRI) Waves (U of Iowa) UV Spectrograph— UVS (SwRI) Visible Camera - JunoCam (Malin) IR Camera/Spectrometer –JIRAM (ASI) Juno’s Science Objectives Origin Determine O/H ratio (water abundance) and constrain core mass to decide among alternative theories of origin. Interior Understand Jupiter's interior structure and dynamical properties by mapping its gravitational and magnetic fields Atmosphere Map variations in atmospheric composition, temperature, cloud opacity and dynamics to depths greater than 100 bars at all latitudes. Magnetosphere Characterize and explore the three-dimensional structure of Jupiter's polar magnetosphere and auroras. 20 Exploring the Polar Magnetosphere Jupiter’s magnetosphere near the planet’s poles is a completely unexplored region! Juno’s investigation will provide new insights about how the planet’s enormous magnetic force field generates the aurora. 21 Juno’s Flight Plan, or Trajectory Salient Features: • First solar-powered mission to Jupiter • Eight science instruments to conduct gravity, magnetic and atmosphericJuno investigations, Mission plus Overview a camera for education and public outreach • Spinning, polar orbiter spacecraft launched on August 5, 2011 – 5-year cruise to Jupiter, arriving July 2016 – About 1 year at Jupiter, ending with de- orbit into Jupiter in 2017 • Elliptical 11-day orbit swings below radiation belts to minimize radiation exposure • 2nd mission in NASA’s New Frontiers Program Science Objective: Improve our understanding of giant planet formation and evolution by studying Jupiter’s origin, interior structure, atmospheric composition and dynamics, and magnetosphere Principal Investigator: Scott Bolton Southwest Research Institute JOI to PJ1 Timeline PJ1 to PRM Timeline .
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