Radiation from Jupiter can destroy molecules on Europa's surface. Material from Europa's ocean that ends up on the surface of Europa will be bombarded by radiation. The radiation breaks apart molecules and changes the chemical composition of the material, possibly destroying any biosignatures, or chemical signs that could imply the presence of life. To interpret what future space missions find on the surface of Europa we must first understand how material has been modified by radiation.
The NASA website hosts a large number of images from the
Soviet/
Russian space agency, and other non-American space agencies. These are not necessarily in the public domain.
The
SOHO (ESA & NASA) joint project implies that all materials created by its probe are copyrighted and require permission for commercial non-educational use.
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