Juno

Spacecraft· NASAactive

Juno — polar Jupiter orbiter probing the planet's interior and magnetosphere.

Open in 3D viewSee Juno in the live, interactive 3D map

Key facts

Current speed

1.86 km/s

Distance from Sun

5.28 AU

Status

Active

Launched

2011

Mission & specifications

Mission

Operator: NASA
Launched: August 5, 2011
Status: Active

Trajectory

Current speed: 1.86 km/s
Distance from the Sun: 5.28 AU
Distance from Earth: 6.25 AU
Distance from Jupiter: 5,793,542 km

Cost & funding

Program cost: $1.13 × 10⁹ USD

Mission

Juno is NASA's mission to look beneath the clouds of Jupiter and read the story of how the Solar System's largest planet — and the Sun's whole family of worlds — came to be. Launched on 5 August 2011, it arrived on 4 July 2016 and slipped into a long, looping polar orbit, swinging close over the cloud tops every few weeks and then retreating far out to escape the planet's punishing radiation belts. Remarkably, it does all this on solar power, its three great panels making it the most distant solar-powered spacecraft ever flown. From its unique vantage over the poles, Juno has transformed our picture of the giant: it found that Jupiter's banded weather reaches thousands of kilometres deep, that its core is not a compact ball but a vast, 'fuzzy' region diluted through the interior, and that its magnetic field is stronger and more lopsided than anyone expected. Its most arresting discovery is at the poles themselves, where clusters of cyclones the size of continents are locked into geometric patterns — eight ringing the north, five the south — unlike anything seen on Earth. Having mapped the planet, Juno's extended mission turned it into a tour of the Jovian system: a close pass of Ganymede in 2021, the first in a generation; a flyby of ocean-bearing Europa in 2022 that scouted ahead of the dedicated missions now en route; and a series of daring approaches to Io through 2023 and 2024, imaging the most volcanic body in the Solar System from as close as 1,500 kilometres. Juno still circles Jupiter, deepening a portrait of the planet that grows richer with every orbit.

2011Launch toward JupiterLaunch
An Atlas V sends the solar-powered Juno on a five-year cruise to the giant planet.
2013Earth gravity assistFlyby
A flyby of home gives Juno the final speed boost toward Jupiter.
2016Jupiter orbit insertionArrival
Juno fires its engine into a looping polar orbit, beginning its survey beneath the clouds.
2018Giant polar cyclones revealedMilestone
The polar orbit reveals clusters of continent-sized cyclones locked into geometric patterns, unlike anything on Earth.
2021Ganymede flybyFlyby
Juno makes the first close pass of the Solar System's largest moon in over twenty years.
2022Europa flybyFlyby
A close pass of ocean-bearing Europa returns detailed images of its fractured ice, scouting for missions to come.
2023Io flybyFlyby
The first of two daring approaches, with a second in February 2024, maps the most volcanic world in the Solar System.

Images

Jupiter's southern hemisphere from Juno (perijove 48) — NASA/JPL-Caltech/SwRI/MSSS (public domain) · Wikimedia Commons

NASA's Juno Spacecraft Glimpses Jupiter's Moons Io and Europa — Image data: NASA/JPL-Caltech/SwRI/MSSS Image processing by Andrea Luck © CC BY · NASA Image Library

Juno Approaches Jupiter (Artist Concept) — NASA/JPL-Caltech · NASA Image Library

Riding Along with Juno — NASA/JPL-Caltech/LEGO · NASA Image Library

Juno testing in Glenn Extreme Environments Rig, GEER Laboratory — NASA/GRC/Bridget Caswell · NASA Image Library

Juno Above Jupiter Pole Artist Concept — NASA/JPL-Caltech · NASA Image Library

Juno is a solar-powered NASA spacecraft that spans the width of a basketball court and makes long, looping orbits around giant planet Jupiter — NASA/GRC/Bridget Caswell · NASA Image Library

Juno Over Jupiter's South Pole (Illustration) — NASA/JPL-Caltech · NASA Image Library

Images from open archives · credit shown per image