Related Experiment Video
Updated: Jun 12, 2026
11:34
Scattering And Absorption of Light in Planetary Regoliths
Published on: July 1, 2019
Europa's ice thickness and subsurface structure characterized by the Juno microwave radiometer
S M Levin1, Z Zhang2, S J Bolton3
1Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA USA.
Nature Astronomy
|January 26, 2026
Summary
New Juno data suggests Jupiter
Area of Science:
- Planetary Science
- Astrobiology
- Geophysics
Background:
- Jupiter's moon Europa is a prime astrobiology target due to its subsurface saltwater ocean.
- The ice shell's thickness varies, and surface disruptions suggest internal cracks, pores, or bubbles.
- Subsurface cracks could potentially facilitate nutrient transport to the ocean, impacting habitability.
Purpose of the Study:
- To investigate the thickness and structure of Europa's ice shell using microwave radiometer data.
- To assess the potential for subsurface features to support habitability by enabling nutrient transport.
Main Methods:
- Analysis of data from the Juno microwave radiometer (2022).
- Modeling of ice shell properties, considering pure water ice and salinity.
- Characterization of subsurface scatterers (cracks, pores) based on radiometer signals.
Main Results:
- The ice shell thickness is estimated at 29 ± 10 km for pure water ice.
- Subsurface features like cracks or pores, with radii < few cm, extend to hundreds of meters depth.
- A salinity of 15 mg/kg reduces the estimated thickness by ~5 km, within the uncertainty.
- The shallow depth and small size of these scatterers suggest they are insufficient for significant nutrient transport.
Conclusions:
- Europa's ice shell is approximately 29 km thick, with small, shallow subsurface scatterers.
- Observed surface fractures are unlikely to connect directly to the ocean for nutrient exchange.
- Further research is needed to understand Europa's habitability potential and ocean-surface exchange mechanisms.
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