Why Is the Innermost Galilean Moon Io Made Mostly of Rock

question 41

Multiple Choice

Why is the innermost Galilean moon Io made mostly of rock while the outermost Galilean moon, Callisto made of a mixture of ice and rock?

• A) Io formed close to Jupiter where the temperatures were too high for ices to form
• B) Callisto was captured as it wandered in from the Kuiper Belt
• C) Io once had ice on its surface which was vaporized away by volcanism
• D) Callisto experience many impact by icy comets which built up a layer of ice on its surface

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Definitions:

Objective Methods

Research or assessment techniques that aim to minimize bias and subjectivity, providing measurable and observable data.

Rational Self-Control

The ability to regulate one's emotions, thoughts, and behaviors in a way that is consistent with long-term goals and societal norms.

Libido

A term used in psychoanalytic theory to describe the energy created by sexual instincts and desire.

Superego

A component of Sigmund Freud's psychoanalytic theory, representing the moral conscience and ideals of society in the individual's personality.