NASA’s Juno space probe entered orbit around Jupiter in 2016.
Juno launched from Cape Canaveral on 5 August 2011 aboard an Atlas V 551 rocket as part of NASA’s New Frontiers program. After a five-year cruise and an Earth gravity assist in 2013, it reached Jupiter and performed orbital insertion on 5 July 2016.
Juno travels in a highly elliptical polar orbit, allowing its instruments to pass close over Jupiter’s cloud tops and then swing far away from the planet. The spacecraft studies Jupiter’s magnetic and gravitational fields, atmosphere, deep winds, auroras, water abundance, and possible rocky core.
Unlike most earlier probes sent to the outer solar system, Juno is powered by solar panels rather than radioisotope generators. Its three large panel wings were especially important because sunlight at Jupiter is much weaker than at Earth. Juno is sometimes confused with Galileo, the first spacecraft to orbit Jupiter; Galileo operated from 1995 to 2003, while Juno began its orbital mission in 2016.