Why Should an Observer Expect to See No Craters, Such

question 10

Multiple Choice

Why should an observer expect to see no craters, such as those on the Moon or Mars, on Io, the innermost Galilean moon of Jupiter?

• A) The continuous water rainfall quickly erodes and washes away any trace of craters.
• B) Volcanoes are continuously depositing new material onto the surface.
• C) The liquid surface cannot maintain a crater, just as Earth's oceans cannot.
• D) The surface is always reentering the planet's interior by subduction in rapid plate tectonic motion, similar to but faster than that on Earth.

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Definitions:

Polarized Light

Light waves where vibrations happen on just one plane.

Specific Rotation

A measure of the degree to which a compound can rotate plane-polarized light, specific to its concentration and the length of the light path through the sample.

(S)-glyceraldehyde

The S-configuration enantiomer of glyceraldehyde, which serves as a standard for determining the absolute configuration of chiral molecules.

(R)-glyceraldehyde

A carbohydrate that is the R-enantiomer of glyceraldehyde, serving as a simple monosaccharide and a basic building block for more complex sugars.