NASA’s Juno exploring Jovian moons during extended mission

After revealing a trove of particulars concerning the moons Ganymede and Europa, the mission to Jupiter is setting its sights on sister moon Io.

NASA’s Juno mission is scheduled to acquire photographs of the Jovian moon Io on Dec. 15 as a part of its persevering with exploration of Jupiter’s interior moons. Now within the second 12 months of its prolonged mission to research the inside of Jupiter, the solar-powered spacecraft carried out a detailed flyby of Ganymede in 2021 and of Europa earlier this 12 months.

“The workforce is de facto excited to have Juno’s prolonged mission embrace the research of Jupiter’s moons. With every shut flyby, we now have been in a position to get hold of a wealth of recent info,” stated Juno Principal Investigator Scott Bolton of the Southwest Analysis Institute in San Antonio. “Juno sensors are designed to check Jupiter, however we have been thrilled at how nicely they’ll carry out double responsibility by observing Jupiter’s moons.”

A number of papers primarily based on the June 7, 2021, Ganymede flyby have been just lately revealed within the Journal of Geophysical Analysis and Geophysical Analysis Letters. They embrace findings on the moon’s inside, floor composition, and ionosphere, together with its interplay with Jupiter’s magnetosphere, from knowledge obtained through the flyby. Preliminary outcomes from Juno’s Sept. 9 flyby of Europa embrace the primary 3D observations of Europa’s ice shell.

Beneath the ice

In the course of the flybys, Juno’s Microwave Radiometer (MWR) added a 3rd dimension to the mission’s Jovian moon exploration: It offered a groundbreaking look beneath the water-ice crust of Ganymede and Europa to acquire knowledge on its construction, purity, and temperature all the way down to as deep as about 15 miles (24 kilometers) under the floor.

Seen-light imagery obtained by the spacecraft’s JunoCam, in addition to by earlier missions to Jupiter, signifies Ganymede’s floor is characterised by a combination of older darkish terrain, youthful shiny terrain, and shiny craters, in addition to linear options which can be doubtlessly related to tectonic exercise.

“After we mixed the MWR knowledge with the floor photographs, we discovered the variations between these numerous terrain varieties aren’t simply pores and skin deep,” stated Bolton. “Younger, shiny terrain seems colder than darkish terrain, with the coldest area sampled being the city-sized impression crater Tros. Preliminary evaluation by the science workforce suggests Ganymede’s conductive ice shell might have a median thickness of roughly 30 miles or extra, with the chance that the ice could also be considerably thicker in sure areas.”

Magnetospheric fireworks

In the course of the spacecraft’s June 2021 shut strategy to Ganymede, Juno’s Magnetic Subject (MAG) and Jovian Auroral Distributions Experiment (JADE) devices recorded knowledge exhibiting proof of the breaking and reforming of magnetic discipline connections between Jupiter and Ganymede. Juno’s ultraviolet spectrograph (UVS) has been observing related occasions with the moon’s ultraviolet auroral emissions, organized into two ovals that wrap round Ganymede.

“Nothing is straightforward—or small—when you have got the largest planet within the solar system as your neighbor,” stated Thomas Greathouse, a Juno scientist from SwRI. “This was the primary measurement of this difficult interplay at Ganymede. This offers us a really early tantalizing style of the knowledge we count on to study from the JUICE [the ESA (European Space Agency) JUpiter ICy moons Explorer] and NASA’s Europa Clipper missions.”

Volcanic future

Jupiter’s moon Io, essentially the most volcanic place within the solar system, will stay an object of the Juno workforce’s consideration for the subsequent 12 months and a half. Their Dec. 15 exploration of the moon would be the first of 9 flybys—two of them from simply 930 miles (1,500 kilometers) away.

Juno scientists will use these flybys to carry out the primary high-resolution monitoring marketing campaign on the magma-encrusted moon, learning Io’s volcanoes and the way volcanic eruptions work together with Jupiter’s highly effective magnetosphere and aurora.