Juno’s goal is to understand the origin and evolution of Jupiter. As the archetype of giant planets, Jupiter can provide the knowledge we need to understand the origin of our own solar system and the planetary systems being discovered around other stars.
Juno will make global maps of the gravity, magnetic fields, and atmospheric composition of Jupiter from a unique polar orbit. Juno’s 32 orbits will extensively sample Jupiter’s full range of latitudes and longitudes. From its polar perspective Juno combines in-situ and remote sensing observations to explore the polar magnetosphere and determine what drives Jupiter’s remarkable auroras. The elliptical orbit swings below radiation belts to minimize radiation exposure.
- Start of ATLO: April 1, 2010
- Launch date: Aug. 5, 2011
- Earth Flyby: October 2013
- Arrival at Jupiter: July 2016
- End of Mission (de-orbit): October 2017
Lockheed Martin designed and built the Juno spacecraft for NASA’s Jet Propulsion Laboratory (JPL). The spacecraft is solar powered and spin-stabilized.
Juno’s payload spans nine instrument suites, comprised of 26 separate sensors.
- Gravity Science: X and Ka-band Doppler gravity measurements will map Jupiter’s interior structure (JPL)
- MAG (Magnetometer): Fluxgate magnetometers guided by advanced stellar cameras map Jupiter’s interior structure and magnetic dynamo (Goddard Space Flight Center and Danish Technical University)
- MWR (Microwave Radiometer): Multiple antennas map Jupiter’s microwave brightness for deep atmosphere sounding and composition (JPL)
- JEDI (Jupiter Energetic-particle Detector Instrument): Particle detectors map electron energy and ion energy/composition over both polar regions (APL/Johns Hopkins University).
- JADE (Jovian Auroral Distributions Experiment): Electron and ion detectors map electron energy and ion energy/composition over both polar regions (Southwest Research Institute)
- Waves: Electric and magnetic antennas measure radio and plasma waves in Jupiter’s polar magnetosphere (University of Iowa)
- UVS (Ultraviolet Spectrometer): Characterizes spatial, spectral and temporal auroral structure (Southwest Research Institute)
- JIRAM (Jupiter Infrared Auroral Mapper): An infrared camera observes the auroral structure, troposphere structure, and atmospheric sounding (SolexGalileo).
- Junocam: An education and public outreach visible-light camera provides first pictures of Jupiter’s poles (Malin Space Science Systems).
Juno’s science objectives span Jupiter’s origin and interior through its atmosphere all the way out to its luminous aurora and polar magnetosphere. Peering down into Jupiter’s atmosphere, Juno reveals fundamental processes of the formation and early evolution of our solar system. Juno’s investigation focuses on four themes:
- Origins: Determine the ratio of oxygen to hydrogen, giving an idea of the abundance of water on Jupiter. Obtain a better estimate of Jupiter's core mass, which will help distinguish among prevailing theories linking the gas giant's formation to the solar system.
- Interior: Precisely map Jupiter's gravitational and magnetic fields to assess the distribution of mass in Jupiter's interior, including properties of the planet's structure and dynamics.
Atmosphere: Map the variation in atmospheric composition, temperature structure, cloud opacity and dynamics to depths far greater than 100 bars at all latitudes.
- Magnetosphere: Characterize and explore the three dimensional structure of Jupiter's polar magnetosphere and its auroras.