Untitled Document
  • Introduction
    • JUNO


      Mission Website


      Juno is a mission of discovery and exploration that will conduct an in-depth study of Jupiter, the most massive planet in our solar system. Peering through the clouds deep into Jupiter's atmosphere, the mission will reveal fundamental processes of the formation and early evolution of our solar system. Juno's goal is to understand the origin and evolution of the gas giant planet, which will pave the way to a better understanding of our solar system and other planetary systems being discovered around other stars.


      Mission Management

      Scott Bolton
      Dr. Scott Bolton,
      Principal Investigator

      The Juno mission is managed for NASA by the Jet Propulsion Laboratory in Pasadena, CA. The Principal Investigator is Dr. Scott Bolton of Southwest Research Institute, San Antonio, TX. The Juno spacecraft was built by Lockheed Martin Space Systems, Denver, CO.

  • Science Objectives
    • Juno's principal goal is to improve our understanding of the solar system's beginnings by revealing the origin, evolution, and structure of Jupiter.

      Juno's science objectives are to:


      Determine how much water is in Jupiter's atmosphere, to help identify which planet formation theory is correct

      Look deep into Jupiter's atmosphere to measure composition, temperature, cloud motions and other properties

      Map Jupiter's magnetic and gravity fields, revealing the planet's deep structure

      Explore and study Jupiter's magnetosphere near the planet's poles, especially the auroras, providing new insights about how the planet's enormous magnetic force field affects its atmosphere.


      entire surface of Pluto

      This simulated view of Jupiter's south pole illustrates Juno's unique perspective which will allow Juno's camera to image Jupiter's clouds from a vantage point never accessed before.


      Juno's investigations focus on four themes:

      Origin – Jupiter's solid core and abundance of heavy metals in the atmosphere make it an ideal model to understand the origin of giant planets. Juno will measure global abundances of oxygen and nitrogen by mapping the gravitational field and using microwave observations of water and ammonia.

      Interior – Juno will map Jupiter's gravitation and magnetic fields, revealing the interior structure, the origin of the magnetic field, the mass of its core, the nature of deep convection, and the abundance of water.

      Atmosphere – Jupiter has the most massive atmosphere of all the planets. By mapping variations in atmospheric composition, temperature, cloud opacity and dynamics to depths greater than 100 bars at all latitudes, Juno will determine the global structure and dynamics of Jupiter’s atmosphere below the cloud tops for the first time.

      Magnetosphere – Jupiter’s powerful magnetospheric dynamics create the brightest aurora in our solar system. Juno will measure the distribution of the charged particles, their associated fields, and the concurrent UV emissions of the planet’s polar magnetosphere, greatly improving our understanding of this remarkable phenomena.

      Auroras at Jupiter's north and south poles.

      Auroras at Jupiter's north and south poles.
      NASA, ESA, and The Hubble Heritage Team (STSci/AURA)


  • Details
    • Juno launched on August 5, 2011, from Cape Canaveral Air Force Station, Florida, aboard an Atlas V-551 rocket. It will fly past the Earth at an altitude of 311 miles on October 9, 2013, for a gravity assist to boost its velocity and send it on the path to Jupiter. It will arrive at the gas giant on July 4, 2016, after traveling 1,740 million miles.

      The Juno spacecraft has three solar arrays that are 29.5 feet long each, carrying a total of 18,698 solar cells. During its one-year mission, the spin-stabilized, solar-powered spacecraft will complete 33 eleven-day-long orbits and will sample Jupiter's full range of latitudes and longitudes.

      To accomplish its science objectives, Juno will orbit over Jupiter's poles and skim to within 3,100 miles above the planet's cloud tops. These close passes will allow it to make extremely precise measurements. This orbital path carries the spacecraft repeatedly through hazardous radiation belts but avoids the most powerful ones.

      Juno's path to Jupiter

      This graphic shows Juno's path to Jupiter: launch on August 5, 2011, Deep Space Maneuvers (DSM) to adjust the trajectory in 2012, an Earth Flyby (EFB) in 2013, and Jupiter Orbit Insertion (JOI) in 2016.

      The Juno spacecraft carries a payload of 29 sensors, which feed data to nine onboard instruments. Eight of these instruments comprise the science payload:


      Gravity Science experiment will enable Juno to measure Jupiter's gravitational field and reveal the planet's internal structure

      Magnetometer (MAG) will create a detailed three-dimensional map of Jupiter's magnetic field

      Microwave Radiometer (MWR) instrument will provide data on the structure, movement, and chemical composition to a depth as great as 1,000 atmospheres — about 342 miles below the visible cloud tops

      Jupiter Energetic Particle Detector Instrument (JEDI) will measure the energetic particles that stream through space and study how they interact with Jupiter's magnetic field

      Jovian Auroral Distributions Experiment (JADE) will work with some of Juno's other instruments to identify the particles and processes that produce Jupiter's stunning auroras

      The Waves instrument will measure radio and plasma waves in Jupiter's magnetosphere to help understand the interactions between the magnetic field, the atmosphere and the magnetosphere

      Ultraviolet Imaging Spectrograph (UVS) will take pictures of Jupiter's auroras in ultraviolet light. Working with the JADE and JEDI instruments, UVS will shed light on the relationship between the auroras, the streaming particles that create them, and the magnetosphere as a whole

      Jovian Infrared Auroral Mapper (JIRAM) will study Jupiter's atmosphere in and around the auroras, helping scientists learn more about the interactions between the auroras, the magnetic field and the magnetosphere


      JunoCam will capture color pictures of Jupiter’s cloud tops in visible light.

               Juno Payload System Overview


  • Noteworthy
    • Jupiter is by far the largest planet in our solar system. Humans have been studying it for hundreds of years, yet many basic questions remain unanswered. In 1995, NASA's Galileo mission dropped a probe into Jupiter's atmosphere. The data returned showed that Jupiter's composition was different than scientists thought, indicating that current theories of planetary formation are wrong. The Juno mission should help answer many questions about the giant planet, and about the origin of our solar system and planetary systems around other stars, such as:

      How did Jupiter form?

      How much water or oxygen is in Jupiter?

      What is the structure inside Jupiter?

      Does Jupiter rotate as a solid body, or is the rotating interior made up of concentric cylinders?

      Is there a solid 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?

      Juno above Jupiter's colorful clouds.

      Artist's rendering of Juno above Jupiter's colorful clouds.

























































































    JUNO Website