Main Theme Origin and evolution of the Giant Planets
Mission Responsibility NASA
Launch Date August 2011
End of Mission October 2017
Current phase Phase B
JUNO, selected in 2005, is the second mission of NASA's New Frontiers programme. It is aimed at observing Jupiter. Its launch is planned for 2011 and it will reach Jupiter's orbit in 2016. After the cruise phase which foresees a fly-by around the Earth planned for 2013, Juno will be inserted into polar orbit around Jupiter with its peri-centre equal to 1.06 Jupiter rays, optimized according to the scientific requirements and also selected in order to minimize exposure of its instruments to radiation. Juno will orbit around Jupiter for a year for a total of 32 orbits.
The Juno mission aims at analyzing Jupiter's characteristics as representative of the Giant Planets. In fact, Jupiter will supply us with the necessary knowledge for understanding the origin of the Solar System and planet systems that are being discovered around the other stars.
The scientific objectives of June mainly involve understanding the origin and evolution of the planet Jupiter (presently there are three different theories on its formation), determining the internal structure of the planet and finding out if it has a solid nucleus, exploring the polar magnetosphere and seeking the origin of the magnetic field, measuring the amount of water, characterising winds in low atmosphere and characterising the amounts relative to oxygen and nitrogen and variations caused by atmosphere conditions. Moreover, another objective of the mission will be to observe the aurora borealis of Jupiter, already observed from the Earth, and to understand its mechanisms, in order to study the planet's magnetic field and its interaction with the atmosphere. With its spinning configuration, Juno will perform a complete map of Jupiter's gravity and magnetic fields and a study of the composition of its atmosphere. In order to reach these objectives particular attention has been put on the definition of the orbit, which will be polar and will undergo a precession motion to obtain a better covering of the planet.
Italian participation is based on its now established experience in the field of spectrometry, optical cameras and radio science. In particular, Italy will supply two instruments: the infrared image spectrometer JIRAM (Jovian InfraRed Auroral Mapper, PI Angioletta Coradini INAF-IFSI, realized by Selex-Galileo Avionica) and the radio science instrument KaT (Ka-Band Translator, PI Luciano Iess of the Università 'La Sapienza' of Rome, realized by Thales Alenia Space-I) which makes up the Ka band portion of the gravity experiment. Both of these instruments will take advantage of important synergies with analogous instruments in development for the BepiColombo mission, optimizing the costs and increasing both the scientific and technological role of Italy.
NASA-ASI Letter of Agreement signed on 21 March 2008.