Juno Steve Levin Juno Project Scientist April 1, 2016

Why Jupiter is so Important It’s the largest planet. Probably formed first. Is very much like the Sun in composition. We lost Earth’s history, but not Jupiter’s.

Salient Features: First solar-powered mission to Jupiter Eight science instruments to conduct gravity, magnetic and atmospheric investigations, plus a camera for education and public outreach Spinning, polar orbiter spacecraft launched on August 5, 2011 –5-year cruise to Jupiter, arriving July 4, 2016 –16 months of science at Jupiter, ending by diving into Jupiter in February 2018 Elliptical 14-day orbit swings below radiation belts to minimize radiation exposure 2 nd 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 Juno Mission Overview

A five-year trek that loops once around the inner solar system before heading for Jupiter Why does it take so long to get there? Direct path would have required a much more powerful launch vehicle Using Earth’s gravity for a boost makes the trip longer, but saves a lot of rocket cost! Juno’s Flight Plan, or Trajectory

How did Jupiter form? How is the planet arranged on the inside? Is there a dense core, and if so, how large is it? How is its vast magnetic field generated? How are atmospheric features related to the movement of the deep interior? What are the physical processes that power the auroras? What do the poles look like? Jupiter is by far the largest planet in the solar system, and we’ve been studying it for hundreds of years. Yet we still have major unanswered questions about this giant planet… Why Juno?

Jupiter’s Temperature K (bottom) to 110 K (top) 10,000 K 30,000 K Jupiter retains heat from its formation 4.5 B years ago It is slowly cooling as heat is transported outwards The atmosphere cools predictably with altitude (like the Earth)

Probing Deep and Globally Microwave radiometry - Magnetic field - Gravity field

Water is key to understanding the formation of Jupiter. Water  Oxygen

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 Understand Jupiter’s interior structure and how material moves deep within the planet 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. Juno Instruments ****Gravity Science (JPL, ASI) ****Magnetometer— MAG (GSFC) ****Microwave Radiometer— MWR (JPL) ****Jupiter Energetic Particle Detector— JEDI (APL) ****Jovian Auroral Distributions Exp.— JADE (SwRI) ****Plasma Waves Instrument— Waves (U of Iowa) ****UV Spectrometer— UVS (SwRI) ****Infrared Camera— JIRAM (ASI) ****Visible Camera— JunoCam (Malin)

Magnetometer (2 sensors, 4 support cameras) JADE (4 sensors ) JEDI (6 sensors ) JIRAM Waves (2 detectors) JunoCam UVS Gravity Science (2 sensors) MWR (6 sensors ) SPACECRAFT DIMENSIONS Diameter: 66 feet (20 meters) Height: 15 feet (4.5 meters) Spacecraft & Payload

The microwave antennas are distributed around the spacecraft and view perpendicular to the spacecraft spin axis Microwave Radiometer (MWR) Experiment Along-track scanning  nadir view off-nadir view emission angle 120° Field of View A1: patch array A3 - A5: slot arrays A2: patch array A6: horn

Juno’s Microwave Radiometer measures thermal radiation from the atmosphere to as deep as 1000 atmospheres pressure (~ km below the visible cloud tops). Determines water and ammonia abundances in the atmosphere all over the planet Sensing the deep atmosphere Synchrotron radio emission from the radiation belts makes this kind of measurement impossible from far away on Earth

Precise Doppler measurements of spacecraft motion reveal the gravity field. Tides provide further clues. Tracking changes in Juno’s velocity reveals Jupiter’s gravity (and how the planet is arranged on the inside). Mapping Jupiter’s gravity

15 Atmospheric Dynamics Radiometry investigates atmospheric structure Gravity investigates differential rotation

Mapping Jupiter’s magnetic field Juno’s polar orbit provides complete mapping of planet’s powerful magnetic field. Jupiter’s magnetic field lets us probe deep inside the planet.

17 Jupiter’s magnetosphere near the planet’s poles is a completely unexplored region! Exploring the Polar Magnetosphere Juno’s investigation will provide new insights about how the planet’s enormous magnetic force field generates the aurora.

18 click on “Junocam” “Science In A Fishbowl”

Spacecraft tracks Education and Science Students contribute to Juno science - Modeling the radiation environment - Providing context for Microwave Radiometer data Juno science lessons (in and out of the classroom) Juno scientists participate in GAVRT teacher training Juno scientists in the (GAVRT) classroom Future plans (Junocam) The Juno/DSN-GAVRT Connection

Juno is part of NASA’s 3D interactive, Eyes on the Solar System… solarsystem.nasa.gov/eyes Fly along with Juno

On the NASA website: For more information... Juno mission website: missionjuno.swri.edu Ask me questions!