Europa has actually been a high concern target for planetary researchers for more than 4 years.

Whether this icy moon of Jupiter is habitable has actually been disputed for several years.

Interest in its habitability significantly increased when measurements by NASA’s Galileo spacecraft suggested the existence of an electrically conductive (salted) water ocean underneath the ice crust and fractures in the surface area ice.

On September 29, 2022, NASA’s Juno spacecraft flew previous Europa at an elevation of 360 km (220 miles).

Throughout the flyby, Juno’s microwave radiometer (MWR), which was created to observe Jupiter’s deep environment, offered measurements of the brightness temperature levels at different depths of Europa’s ice-shell crust.

Utilizing the MWR information, Juno task researcher Steve Levin and his associates figured out that the shell averages about 29 km thick.

“The 29-km price quote associates with the cold, stiff, conductive outer-layer of a distilled water ice shell,” Dr. Levin stated.

“If an inner, somewhat warmer convective layer likewise exists, which is possible, the overall ice shell density would be even higher.”

“If the ice shell includes a modest quantity of liquified salt, as recommended by some designs, then our price quote of the shell density would be lowered by about 5 km (3 miles).”

“The thick shell, as recommended by the MWR information, suggests a longer path that oxygen and nutrients would need to take a trip to link Europa’s surface area with its subsurface ocean.”

“Understanding this procedure might relate to future research studies of Europa’s habitability.”

The MWR information likewise supply brand-new insights into the makeup of the ice simply listed below Europa’s surface area.

The instrument exposed the existence of ‘scatterers’– abnormalities in the near-surface ice such as fractures, pores, and spaces that spread the instrument’s microwaves showing off the ice.

These scatterers are approximated to be no larger than a couple of inches in size and appear to reach depths of numerous feet listed below Europa’s surface area.

The little size and shallow depth of these functions, as designed in this research study, recommend they are not likely to be a substantial path for oxygen and nutrients to take a trip from Europa’s surface area to its salted ocean.

“How thick the ice shell is and the presence of fractures or pores within the ice shell become part of the complex puzzle for comprehending Europa’s prospective habitability,” stated Juno’s primary detective Dr. Scott Bolton, a scientist at the Southwest Research Institute.

“They supply vital context for NASA’s Europa Clipper and ESA’s Juice spacecraft– both of which are on their method to the Jovian system.”

“Europa Clipper will show up there in 2030, while Juice will show up the year after.”

The group’s brand-new outcomes were released on December 17, 2025 in the journal Nature Astronomy

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S.M. Levin et al2026. Europa’s ice density and subsurface structure identified by the Juno microwave radiometer. Nat Astron 10, 84-91; doi: 10.1038/ s41550-025-02718-0