Equation 2 · How We Know What Is Inside a Planet
What does this equation mean?
Read the formula alongside the article passage below. Each part has a deeper page with its role in the equation, the supporting passage and nearby citations.
This equation states an equality: the expressions on both sides have the same value under the article’s assumptions. Read the equation part by part below; each part has a contextual explanation and a link to its mathematical background.
Read it piece by piece
Symbol I^*
is part of the quantity the equation computes from the expression on the right.
=
The expressions on both sides represent the same quantity under the stated assumptions.
See an illustrated explanation →superscript
A raised number can be a power. When it is a label or bound, it selects a case or the upper limit of a sum; the formula’s structure distinguishes these uses.
See an illustrated explanation →How to interpret it
Read it with the definitions, units, and assumptions supplied by the article.
What the article says around this equation
and it measures how mass is distributed radially rather than how much there is. A uniform sphere has = 0.4 . Anything smaller means mass concentrated toward the centre; anything approaching 0.4 means a body that is close to uniform in density, which for a rocky planet means undifferentiated.
Sources cited in the article section
- [7] Gravity field and internal structure of Mercury from MESSENGER ↗
- [9] Geodetic evidence that Mercury has a solid inner core ↗
These citations give research context. Read each source to check which claims it supports.
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