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Updated: Aug 4, 2026
06:04
Simulation of the Planetary Interior Differentiation Processes in the Laboratory
Published on: November 15, 2013
Europa's differentiated internal structure: inferences from two Galileo encounters
J D Anderson1, E L Lau, W L Sjogren
1Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109-8099, USA.
Science (New York, N.Y.)
|May 23, 1997
Summary
Galileo spacecraft data reveal Europa
Area of Science:
- Planetary Science
- Geophysics
- Astrobiology
Background:
- Europa, Jupiter's moon, is a prime candidate for extraterrestrial life.
- Understanding Europa's internal structure is crucial for assessing its habitability.
Purpose of the Study:
- To determine Europa's external gravitational field.
- To infer the moon's internal structure and composition.
Main Methods:
- Analysis of Doppler data from the Galileo spacecraft's radio carrier wave.
- Measurements during two Europa encounters (E4 and E6).
Main Results:
- Europa possesses a thick outer shell (100–200 km) of water ice and liquid.
- The moon's deep interior has a density exceeding 4000 kg/m³.
- A metallic core (radius ~40% of Europa's) surrounded by a rock mantle (3000–3500 kg/m³) is a possible internal configuration.
Conclusions:
- Europa's structure suggests a subsurface ocean beneath an icy crust.
- The presence of a metallic core is supported by the possibility of a magnetic field.
- These findings have implications for Europa's potential to host life.
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