SUMMARY: The cores of all 4 jovian planets space made of some mix of rock, metal and also hydrogen compounds. The difference in between the jovian interiors stays in the layers that surround the core.

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Sections:Planetary Size and also DensityInterior StructureInternal HeatRelated linksRelated Lessons:Looking inside Planets

Have you ever before wondered why Jupiter and Saturn are an extremely close in size, but Jupiter"s average thickness is nearly twice Saturn"s? The prize lies in exactly how you develop a earth out of hydrogen and helium. The procedure is similar to stacking pillows one on optimal of another. As much more pillows are stacked top top top, the pillows ~ above the bottom become more and much more compressed. The bottom pillows proceed to compress until a suggest when adding pillows doesn"t increase the height of the stack.

Planet Radius vs. Mass(click to enlarge)

This helps explain why the radii the Jupiter and Saturn are really close, but Jupiter is an ext than 3 times together massive. Jupiter ongoing to collection hydrogen and helium in its atmosphere, boosting its mass and also compressing its internal until the average thickness was twice Saturn"s.

Average density (from highest to lowest)Neptune 1,638 kg/m3Jupiter 1,326 kg/m3Uranus 1,270 kg/m3Saturn 687 kg/m3

Notice that also though Neptune and also Uranus are smaller in size, your densities are much larger than Saturn"s. This leads united state to believe that Uranus and Neptune should have substantially different compositions than that the Saturn, with a lot larger fraction of higher-density product such together hydrogen compounds and rock.

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All four jovian world cores are similar in composition. Each consists of a mixture the rock, metal and hydrogen compounds. Their distinctions stem indigenous having captured different quantities of extr hydrogen and helium gas indigenous the solar nebula. Jupiter recorded so lot that it finished up through 300 time Earth"s mass.

Jovial world Interiors(click come enlarge)
A Pie slice of Jupiter"s Density
LAYERS neighboring JOVIAN CORES (FROM main point OUTWARD):Jupiter and SaturnMetallic hydrogenLiquid hydrogenGaseous hydrogenVisible cloudsUranus and also NeptuneGaseous hydrogenVisible cloudsDensity, temperature and pressure increase with distance from the cloud tops.

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The jovian planets acquire their warm from the Sun and also from your interiors. Jupiter creates a many of internal heat and also releases this heat by emitting thermal radiation. In fact, Jupiter creates so much internal warmth that it emits virtually twice as much power as it receives native the Sun. The just reasonable explanation is that Jupiter is still progressively contracting, almost as despite it has actually not fairly finished forming.

Saturn and Neptune likewise appear to it is in emitting more energy than they obtain from the Sun. While us are particular Saturn is not still contracting, it appears clear that Neptune is still contracting. Uranus is the just jovian planet not create excess interior energy.