Juno activated its whole suite of nine instruments as it soared 2,600 miles above Jupiter’s swirling cloud tops, travelling at 130,000mph.
Right on schedule, Nasa tweeted that Juno had successfully completed its closest ever fly-by to the planet, the first of 36, which are scheduled to end in February 2018.
Rick Nybakken, Juno’s project manager at Nasa’s Jet Propulsion Laboratory in Pasadena, California, said: “Early post-fly-by telemetry indicates that everything worked as planned and Juno is firing on all cylinders.”
Mission controllers at the space agency expect to capture stunning images and a wealth of scientific data from the approach, but it will take some days for all the data collected to be downloaded on Earth.
Scott Bolton, principal investigator of Juno from the Southwest Research Institute in San Antonio, said: “It will take days for all the science data collected during the fly-by to be downlinked and even more to begin to comprehend what Juno and Jupiter are trying to tell us. This is our first opportunity to really take a close-up look at the king of our solar system and begin to figure out how he works.”
Nasa hopes to release a handful of close-up images from JunoCam, the probe’s panoramic colour camera, during the later part of this week. They should include the first detailed pictures of Jupiter’s north and south poles.
In total, 35 more close fly-bys are planned during Juno’s primary mission.
No previous spacecraft has flown so close to Jupiter before.
The previous record for a close approach to the planet was set by Nasa’s Pioneer 11, which passed at a distance of 27,000 miles in 1974.
Only one other spacecraft, Galileo, which visited Jupiter and its moons from 1995 to 2003, has orbited the planet. Although it was deliberately crashed on to Jupiter at the end of its mission, it orbited from much further out than Juno.
Powered by three huge solar panels, Juno was launched into space by an Atlas V rocket from Cape Canaveral, Florida, on 5 August 2011. It took five years to complete the 1.8 billion-mile journey from Earth.
The probe has had to be specially strengthened to withstand the circuit-frying radiation around Jupiter. Its flight computer is in an armoured vault made of titanium and weighs almost 400lb.
At the end of its 20-month mission, Juno will follow in the footsteps of Galileo by making a one-way plunge into the planet’s thick atmosphere.
Scientists are eagerly looking forward to analysing a treasure trove of data about Jupiter’s composition, gravity, magnetic field, and the source of its raging 384mph winds.
A British team from the University of Leicester is playing a key role in the mission, focusing on Jupiter’s powerful magnetic field, its spectacular auroras, and its dynamic atmosphere.
Juno is part of Nasa’s New Frontiers programme of robotic space missions which last year saw the New Horizons craft obtain close-up views of dwarf planet Pluto.
Unusually for a robotic space mission, the probe is carrying passengers – three Lego figures depicting the 17th-century Italian astronomer Galileo Galilei, the Roman god Jupiter, and the deity’s wife, Juno.