Equation 10 · Part 1 · How We Know What Is Inside a Planet

Symbol J_2

J_{2}

J_{2}

What this part means

$J_2$ is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.

Its job in the formula

$J_2$ is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.

Full expressionSymbol J_2Article meaning

The passage around this formula

For the giant planets, only low-degree harmonics are available, and the interpretation problem sharpens. Juno measured Jupiter’s even zonal harmonics $J_{2}$ through $J_{8}$ to high precision, and Wahl and colleagues found that models fit those moments best when the heavy-element core is not compact but dilute, expanded over a significant fraction of the planet’s radius, with total heavy-element content in the core region of roughly 7 to 25 Earth…

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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 surrounding passage

[17] Comparing Jupiter interior structure models to Juno gravity measurements and the role of a dilute core ↗

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