Scientists find evidence for magnetic reconnection between Ganymede and Jupiter

In June 2021, NASA’s Juno spacecraft flew near Ganymede, Jupiter’s largest moon, observing proof of magnetic reconnection. A staff led by Southwest Analysis Institute used Juno knowledge to look at the electron and ion particles and magnetic fields because the magnetic subject strains of Jupiter and Ganymede merged, snapped and reoriented, heating and accelerating the charged particles within the area.

“Ganymede is the one moon in our solar system with its personal magnetic field,” mentioned Juno Principal Investigator Dr. Scott Bolton of SwRI. “The snapping and reconnecting of Ganymede’s magnetic subject strains with Jupiter’s creates the magnetospheric fireworks.”

Magnetic reconnection is an explosive bodily course of that converts saved magnetic power into kinetic power and warmth. Ganymede’s mini-magnetosphere interacts with Jupiter’s huge magnetosphere, within the magnetopause, the boundary between the 2 areas.

“We interpreted the presence of accelerated electrons touring alongside the magnetic subject at Ganymede’s magnetopause as proof that magnetic reconnection was occurring there in the course of the Juno flyby,” mentioned Dr. Robert Ebert, lead writer of a Geophysical Analysis Letters paper describing the findings. “These observations additional assist the notion that magnetic reconnection at Ganymede’s magnetopause generally is a driver of dynamic processes within the native space surroundings round this moon of Jupiter.”

The SwRI-developed Jovian Auroral Distributions Experiment (JADE) aboard Juno noticed enhanced electron fluxes, together with accelerated, magnetic field-aligned electrons. Reconnection as noticed by Juno is regarded as associated to the era of Ganymede’s aurora.

“The accelerated electrons noticed by JADE are just like these noticed by NASA’s Magnetospheric Multiscale (MSS) spacecraft throughout reconnection on the Earth’s magnetopause,” mentioned Dr. Stephen Fuselier, a co-author of the paper. “That is one of many thrilling outcomes from the Ganymede flyby: Regardless of the huge variations between Ganymede and Earth, we discover commonality within the common strategy of magnetic reconnection.”

Throughout the Juno flyby, the SwRI-led Ultraviolet Spectrograph (UVS) noticed Ganymede’s auroral emissions, that are anticipated to be produced by electrons accelerated by way of magnetic reconnection.

SwRI has constructed two further UVS devices to function in Jupiter orbit aboard ESA’s JUpiter ICy moons Explorer (JUICE) spacecraft and NASA’s Europa Clipper. The European House Company’s JUICE mission is scheduled to launch in April 2023 and arrive at Jupiter in 2031. NASA’s Europa Clipper is scheduled to launch in October 2024 and arrive at Jupiter in 2030.

“Nothing is easy—or small—when you’ve got the most important planet within the solar system as your neighbor,” mentioned Thomas Greathouse, a Juno scientist from SwRI. “This was the primary measurement of this difficult interplay at Ganymede. This provides us a really early tantalizing style of the knowledge we anticipate to be taught from ESA’s JUICE mission.”