*This JunoCam picture of Loki Patera (proper of centre) was captured in February 2024 throughout Juno’s 58th flyby of Jupiter. The brightness of the characteristic is brought on by daylight reflecting off the stable lava floor, in the identical means that mild is mirrored by a mirror, aka specular reflection. (NASA/JPL-Caltech/SwRI/MSSS/Gerald Eichstädt/Thomas Thomopoulos)*
The closest photos but of Jupiter’s volcanic moon have revealed one of many main floor options is almost as easy as a sheet of glass!
In December 2023 and February 2024, NASA’s Juno spacecraft made shut passes by Io, the innermost of Jupiter’s 4 massive Galilean moons. Throughout these flybys, Juno got here inside 1,500 km of Io and used the JunoCam instrument to snap the closest views but of this distinctive moon’s floor.
“Io is solely suffering from volcanoes, and we caught a couple of of them in motion,” Scott Bolton, the precept investigator for the Juno mission, mentioned in a information convention on the 2024 European Geophysical Union Basic Meeting on April 16.
A picture of Jupiter’s moon Io, captured throughout the Juno spacecraft’s 57th flyby of Jupiter, in December 2023, captured a tremendous take a look at Loki Patera, an immense volcanic lake within the moon’s northern hemisphere. (NASA/JPL-Caltech/SwRI/MSSS/Kevin M. Gill)
“We additionally bought some nice close-ups and different information on a 200-kilometre-long lava lake referred to as Loki Patera. There may be superb element exhibiting these loopy islands embedded in the course of a doubtlessly magma lake rimmed with scorching lava,” Bolton defined.
Among the views captured throughout Juno’s flyby gave the mission group a particular deal with. They had been in a position to see mild reflecting off Loki Patera’s stable crust, revealing its remarkably easy floor.
“The specular reflection our devices recorded of the lake suggests components of Io’s floor are as easy as glass, paying homage to volcanically created obsidian glass on Earth,” Bolton added.
A zoomed view of the earlier picture highlights the sleek reflective floor of Loki Patera. (NASA/JPL-Caltech/SwRI/MSSS/Gerald Eichstädt/Thomas Thomopoulos)
Whereas Loki Patera is called a lava lake, underneath its cooled stable floor is a reservoir of molten magma (the identify for liquid rock that’s underground). In the meantime, hot-spots alongside the perimeters of the characteristic reveal areas of rising lava (the identify for molten rock that’s above floor).
Bolton was cautious to specify that the floor of Loki Patera is solely paying homage to obsidian glass. Whereas it could have fashioned in a really comparable means, by the fast cooling of lava, it is probably not composed of the identical supplies as obsidian right here on Earth.
Watch beneath: Information from JunoCam was used to create this artist’s conception of Loki Patera and the way the sunshine from Jupiter would replicate off its glass-like floor
NASA calls Io probably the most volcanically lively world within the photo voltaic system.
In accordance with the area company, the exceptional volcanic exercise we see on Io is because of tidal forces.
The extraordinary gravitational pull of Jupiter mixed with exactly timed tugs exerted by neighbouring moons, Europa and Ganymede, squeeze and squash Io, superheating its inside. Thus, other than a cast-iron core within the center and a skinny shell across the outdoors, Io is probably going totally molten inside.
This infrared picture of Io was lately captured by Juno’s JIRAM instrument and shared by Bolton throughout the April 16 EGU24 press convention. The intense ‘ring’ good of centre exhibits the warmth from magma underlying the stable floor of Loki Patera. Credit score: NASA/JPL-Caltech/SwRI/ASI/INAF/JIRAM
The result’s that Io’s floor is studded with an estimated 400 lively volcanoes, which continuously renew its options with lava escaping from the inside.
As of April 9, 2024, Juno accomplished its sixtieth shut move round Jupiter (‘perijove’). Included on this was a further encounter with Io, however at a distance of 16,500 kilometres. Thus, it seems that the December 2023 and February 2024 flybys (perijove 57 & 58, respectively) will likely be our closest appears at Io for a while.
Juno’s subsequent flyby of Jupiter, perijove 61, is anticipated on Might 12. NASA at present has a complete of 16 extra perijoves deliberate between now and September 2025.
