Equation 14 · Part 1 · How We Know What Is Inside a Planet
Symbol k_2
What this part means
the small.
Its job in the formula
is part of the quantity the equation computes from the expression on the right.
Full expression→Symbol k_2→Article meaning
Where the article explains it
A rigid body has a small ; a body with a global liquid layer decoupling shell from interior has a large one.
The passage around this formula
Cassini flew six flybys of Titan between 2006 and 2011 with a gravity-quality radio link, and Iess and colleagues recovered = 0.589 0.150 , with an alternative solution of 0.637 0.224 [ 14 ] . Both are far too large for a rigid ice shell over rock and are consistent with a global ocean at depth [ 14 ] . The measurement did not see the ocean; it measured how much the whole moon flexes each orbit, and only a decoupled shell flexes that much.
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
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