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Equation 12 · Part 1 · How We Know What Is Inside a Planet

Symbol k_2

k2k_{2}
k2k_{2}

What this part means

the small.

Its job in the formula

k2k_2 is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.

Where the article explains it

A rigid body has a small k2k_{2} ; a body with a global liquid layer decoupling shell from interior has a large one.

The passage around this formula

If a body is deformable, an external tidal potential distorts it, and the distortion changes its external gravity field in a way an orbiter can measure. The degree-two potential Love number k2k_{2} quantifies that response. A rigid body has a small k2k_{2} ; a body with a global liquid layer decoupling shell from interior has a large one.

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Learn the underlying idea

A subscript is a label attached below a symbol. It often selects a time step, component, category, or member of a sequence.

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Sources cited in the article section

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