Juno Spacecraft


Juno spacecraft is a NASA mission to Jupiter and is the second NASA New Frontiers mission. The launch of the Juno mission was on 5 August 2011 and arrived at Planet Jupiter on 4 July 2016. It is the first mission to Jupiter using solar panels instead of radioisotope thermoelectric generators.

Juno Spacecraft orbiting Planet Jupiter Picture

Why is the mission named Juno?

Juno, the god-sister-wife of Jupiter, maintained a constant, jealous vigil over her god-husband’s dalliances from Mount Olympus. When Jupiter had his tryst with Io, he spread a veil of clouds around the entire planet to conceal his activities. Upon observing the cloud-cloaked planet, Juno immediately suspected Jupiter of concealing activities that would not bear the light. Hence, Juno came down from Mount Olympus and employed her special powers to penetrate the clouds and reveal the true nature of Jupiter.

Mission Timeline

2005: Juno Selected
2011: Launched 5th August
2013: Earth Fly-by
2016: Jupiter Arrival
2017: Mission End
2018: Data Analysis


The mission will conduct an in-depth study of the giant planet. The mission proposes to place a spacecraft in a polar orbit around Planet Jupiter to investigate the existence of an ice-rock core; determine the amount of global water and ammonia present in the atmosphere, study convection and deep wind profiles in the atmosphere, investigate the origin of the jovian magnetic field and explore the polar magnetosphere.

Juno Spacecraft Picture

When the solar-powered spacecraft reaches its final destination in 2016, Juno will enter into a low, elliptical orbit circling the planet from pole to pole. The Juno team has carefully plotted the orbit of the innovative spacecraft to avoid lethal belts of charged particles that surround Jupiter much like the less dense Van Allen belts that encircle the Earth.

Once Juno enters into its orbit, infrared and microwave instruments will begin to measure the thermal radiation emanating from deep within Jupiter’s dense atmosphere. These observations will complement previous studies of the planet’s composition by assessing the abundance and distribution of water, and therefore oxygen. While filling missing pieces of the puzzle of Jupiter’s composition, this data also provides insight into the planet’s origins.

Meanwhile, other instruments aboard Juno will gather data about the planet’s gravitational field and polar magnetosphere. Scientists can use this information to expand our understanding of the processes that cause Jupiter’s spectacular auroras and the baffling internal structure of a world made mainly of hydrogen and helium.


NASA announced on June 1 2005 that a mission to fly to Jupiter will proceed to a preliminary design phase. The mission was called Juno and it was the second in NASA’s New Frontiers Program.

Dr. Scott Bolton of Southwest Research Institute, San Antonio, Texas is the principal investigator. NASA’s Jet Propulsion Laboratory, Pasadena, California will provide mission project management. Lockheed Martin Space Systems, Denver will build the spacecraft.

NASA selected two proposed mission concepts for study in July 2004 from seven submitted in February 2004 in response to an agency Announcement of Opportunity.

Juno mission was launched on 5 August 2011 and began a five-year journey to Planet Jupiter to uncover the secrets hidden beneath the planet’s thick, colourful clouds.

Juno probe arrived at Planet Jupiter on 4 July 2016.

Did you know?

The first NASA New Frontiers mission will fly by the Pluto-Charon system in 2014 and then target another Kuiper asteroid belt object.

Juno is the second spacecraft to orbit Jupiter, following the Galileo probe which orbited from 1995–2003.

The New Frontiers Program is designed to provide opportunities to conduct several of the medium-class missions identified as top priority objectives in the Decadal Solar System Exploration Survey, conducted by the Space Studies Board of the National Research Council.

Related Book:

The Giant Planet Jupiter by John H. Rogers
From Amazon.comAmazon.co.uk

Juno Spacecraft Links:

NASA Selects New Frontiers Mission Concept Study: JPL News

Juno / NASA: