NASA’s solar-powered spacecraft Juno has sent back another tranche of images from 560 million miles (900 million kilometers) away.
The bus-sized spacecraft, which has been in Jupiter’s orbit since 2016, captured more wonderful images of the giant planet during a close pass of its polar regions.
It comes just in time because Jupiter will be in what astronomers call superior conjunction on May 18 when it passes behind the sun as seen from Earth.
Juno orbits Jupiter every 34 days but along a hugely elliptical path, so it only gets close to Jupiter for a few hours each month. That short period—called a perijove—occurred last Sunday, Juno’s 61st. During a perijove, Juno dips close to the cloud tops of Jupiter.
Juno orbits Jupiter every 34 days but along a hugely elliptical path, so it only gets close to Jupiter for a few hours each month. That short period—called a perijove—occurred last Sunday, Juno’s 61st. During a perijove, Juno dips close to the cloud tops of Jupiter.
Juno’s camera is activated during each perijove. A two-megapixel camera only ever intended for outreach and not for science, JunoCam has, in recent months, been activated early to photograph some of Jupiter’s moons prior to its perijove with the giant planet.
Last month, it captured Europa, an ice-covered moon thought to contain a subterranean ocean. In March, a paper published in Nature Astronomy used Juno’s Jovian Auroral Distributions Experiment (JADE) instrument to measure the amount of oxygen produced by Europa. It found that the tiny moon generates 1,000 tons of oxygen every 24 hours.
Planetary scientists think that if some of the oxygen produced on Europa finds its way into the moon’s ocean, it could be a possible source of metabolic energy, which would allow lifeforms to exist. Europa is the fourth largest of Jupiter’s 95 known moons.
“Our ability to fly close to the Galilean satellites during our extended mission allowed us to start tackling a breadth of science, including some unique opportunities to contribute to the investigation of Europa’s habitability,” said Scott Bolton, Juno’s principal investigator from the Southwest Research Institute in San Antonio. “And we’re not done yet. More moon flybys and the first exploration of Jupiter’s close ring and polar atmosphere are yet to come.”
Juno has also recently been imaging Jupier’s innermost moo, Io. This world is, the most volcanic in the solar system, with eruptions orders of magnitude bigger than anything similar on Earth.
Data from Juno’s extremely close flybys of Io in December 2023 and February 2024, both within about 930 miles (1,500 kilometers) of the surface, was the first-ever in Io’s northern latitudes. It was transformed into an animation featuring a mountain and Loki Patera, a lake of cooling lava on Io.
The next two spacecraft due at Jupiter—NASA’s Europa Clipper in April 2030 and ESA’s JUpiter ICy moons Explorer (JUICE) in 2031—will focus on Europa, Callisto and Ganymede.
The $1.1 billion solar-powered spacecraft was launched on August 5, 2011, and began to orbit Jupiter on July 4, 2016. Juno carries 11 science instruments designed to study the Jovian system.
Juno’s 62nd perijove will occur on June 14, and its mission will be completed on September 15, 2025, when Juno will perform a “death dive” into the gas giant during its 76th perijove.
Wishing you clear skies and wide eyes.
Dr. Thomas Hughes is a UK-based scientist and science communicator who makes complex topics accessible to readers. His articles explore breakthroughs in various scientific disciplines, from space exploration to cutting-edge research.