Equation 3 · Part 1 · How We Know What Is Inside a Planet

Symbol I^*

I^{*}

I^{*}

What this part means

$I^*$ 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

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

Full expressionSymbol I^*Article meaning

The passage around this formula

…than what it establishes. It is a single number, so it cannot distinguish a small dense core under a light mantle from a larger, less dense core under a heavier one; infinitely many radial density profiles share the same $I^{*}$ . But it will refuse an entire class of models outright. For Mercury, MESSENGER radio tracking combined with spin measurements gave C/M $R^{2}$ = 0.353 $\pm$ 0.017 together with a ratio of mantle-plus-crust moment to total moment of 0.452 $\pm$ 0.035 , a combination consistent with a solid silicate…

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Learn the underlying idea

An exponent tells how a base is used in multiplication. In x³, x is the base and 3 is the exponent: x³ = x × x × x.

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Sources cited in the surrounding passage

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